Objective Cerebral palsy(CP)is a prevalent neurodevelopmental disorder acquired during the perinatal period,with periventricular white matter injury(PWMI)serving as its primary pathological hallmark.PWMI is characteri...Objective Cerebral palsy(CP)is a prevalent neurodevelopmental disorder acquired during the perinatal period,with periventricular white matter injury(PWMI)serving as its primary pathological hallmark.PWMI is characterized by the loss of oligodendrocytes(OLs)and the disintegration of myelin sheaths,leading to impaired neural connectivity and motor dysfunction.Neural stem cells(NSCs)represent a promising regenerative source for replenishing lost OLs;however,conventional twodimensional(2D)in vitro culture systems lack the three-dimensional(3D)physiological microenvironment.Microfluidic chip technology has emerged as a powerful tool to overcome this limitation by enabling precise spatial and temporal control over 3D microenvironmental conditions,including the establishment of stable concentration gradients of bioactive molecules.Catalpol,an iridoid glycoside derived from traditional medicinal plants,exhibits dual antioxidant and anti-apoptotic properties.Despite its therapeutic potential,the capacity of catalpol to drive NSC differentiation toward OLs under biomimetic 3D conditions,as well as the underlying molecular mechanisms,remains poorly understood.This study aims to develop a microfluidic-based 3D biomimetic platform to systematically investigate the concentration-dependent effects of catalpol on promoting NSCs-to-OLs differentiation and to elucidate the role of the caveolin-1(Cav-1)signaling pathway in this process.Methods We developed a novel multiplexed microfluidic device featuring parallel microchannels with integrated gradient generators capable of establishing and maintaining precise linear concentration gradients(0-3 g/L catalpol)across 3D NSCs cultures.This platform facilitated the continuous perfusion culture of NSC-derived 3D spheroids,mimicking the dynamic in vivo microenvironment.Real-time cell viability was assessed using Calcein-AM/propidium iodide(PI)dual staining,with fluorescence imaging quantifying live/dead cell ratios.Oligodendrocyte differentiation was evaluated through quantitative reverse transcription polymerase chain reaction(qRT-PCR)for MBP and SOX10 gene expression,complemented by immunofluorescence staining to visualize corresponding protein changes.To dissect the molecular mechanism,the Cav-1-specific pharmacological inhibitor methyl‑β‑cyclodextrin(MCD)was employed to perturb the pathway,and its effects on differentiation markers were analyzed.Results Catalpol demonstrated excellent biocompatibility,with cell viability exceeding 96%across the entire tested concentration range(0-3 g/L),confirming its non-cytotoxic nature.At the optimal concentration of 0-3 g/L,catalpol significantly upregulated both MBP and SOX10 expression(P<0.05,P<0.01),indicating robust promotion of oligodendroglial differentiation.Intriguingly,Cav-1 mRNA expression was progressively downregulated during NSC differentiation into OLs.Further inhibition of Cav-1 with MCD further enhanced this effect,leading to a statistically significant increase in OL-specific gene expression(P<0.05,P<0.01),suggesting Cav-1 acts as a negative regulator of OLs differentiation.Conclusion This study established an integrated microfluidic gradient chip-3D NSC spheroid culture system,which combines the advantages of precise chemical gradient control with physiologically relevant 3D cell culture.The findings demonstrate that 3 g/L catalpol effectively suppresses Cav-1 signaling to drive NSC differentiation into functional OLs.This work not only provides novel insights into the Cav-1-dependent mechanisms of myelination but also delivers a scalable technological platform for future research on remyelination therapies,with potential applications in cerebral palsy and other white matter disorders.The platform’s modular design permits adaptation for screening other neurogenic compounds or investigating additional signaling pathways involved in OLs maturation.展开更多
Multi-layer microbubble has great potential in enabling the corporation of medical imaging with tumor therapy such as drug and gene delivery of therapeutics or other functional materials in medical applications. Micro...Multi-layer microbubble has great potential in enabling the corporation of medical imaging with tumor therapy such as drug and gene delivery of therapeutics or other functional materials in medical applications. Microfluidic technique has advanced over the last decade and showed great promise in replacing traditional microbubble generating method. In this paper, a multi-layer microbubble structure was produced with the aspect as potentially used for drug loaded microbubble contrast agents.展开更多
The development of pharmaceutical analytical methods represents one of the most significant aspects of drug development. Recent advances in microfabrication and microfluidics could provide new approaches for drug anal...The development of pharmaceutical analytical methods represents one of the most significant aspects of drug development. Recent advances in microfabrication and microfluidics could provide new approaches for drug analysis, including drug screening, active testing and the study of metabolism. Microfluidic chip technologies, such as lab-on-a-chip technology, three-dimensional (3D) cell culture, organs-on-chip and droplet techniques, have all been developed rapidly. Microfluidic chips coupled with various kinds of detection techniques are suitable for the high-throughput screening, detection and mechanistic study of drugs. This review highlights the latest (2010–2018) microfluidic technology for drug analysis and discusses the potential future development in this field.展开更多
In this work,a multi-functional analysis platform by coupling a microfluidic chip to a mass spectrometry(MS) detector was described.We constructed a three-dimensional tumor-endothelial co-culture model for simulating ...In this work,a multi-functional analysis platform by coupling a microfluidic chip to a mass spectrometry(MS) detector was described.We constructed a three-dimensional tumor-endothelial co-culture model for simulating drug resistance during tumor treatment.On this specially designed integrated platform,the first step was to prepare heterogeneous cell-encapsulated alginate microcapsules for threedimensional co-culture,and the second step was to achieve on-line perfusion culture and continuous drug stimulation on chip.It facilitates cell proliferation analysis and the collection of metabolism medium.After micro solid phase extraction column(SPE) pretreatment,subsequent mass spectrometry could detect drug metabolism.The high activity of two kinds of cells(A549 and HUVEC) shows the biocompatibility of the platform.Paclitaxel was used as a model drug,the distinctions of drug absorption between the mono-culture group and co-culture group were clearly observed by electrospray ionization quadrupole time-of-flight mass spectrometry(ESI-Q-TOF MS).Therefore,the integrated platform has shown promise as a high throughput,low cost for cell metabolism research and drug screening processes.展开更多
Experiments are used to study the fabrication of polymer microfluidic chip with hot embossing method. The pattern fidelity with respect to the process parameters is analyzed. Experiment results show that the relations...Experiments are used to study the fabrication of polymer microfluidic chip with hot embossing method. The pattern fidelity with respect to the process parameters is analyzed. Experiment results show that the relationship between the imprint temperature and the microchannel width is approximately exponential. However, the depth of micro channel isn＇t sensitive to the imprint temperature. When the imprint pressure is larger than 1 MPa and the imprint time is longer than 2 min, the increasing of imprint pressure and holding time has little impact on the microchannel width. So over long holding time is not needed in hot embossing. Based on the experiment analysis, a series of optimization process parameters is obtained and a fine microfluidic chip is fabricated. The electrophoresis separation experiment are used to verify the microfluidic chip performance after bonding. The results show that 100bp-ladder DNA sample can be separated in less than 5 min successfully.展开更多
The first example of the microfluidic chips(MFCs) consisting of centimeter-level 3D channels with highdensity and large-volume fabricated by femtosecond laser micromachining were utilized to develop a time-saving, eco...The first example of the microfluidic chips(MFCs) consisting of centimeter-level 3D channels with highdensity and large-volume fabricated by femtosecond laser micromachining were utilized to develop a time-saving, economical and hazardless flow synthesis process, and its advantages have been proved by in situ formation of aryldiazonium salts and subsequent borylation with bis(pinacolato)diboron. There are several important advantages in our 3D MFC-based flow synthesis technology, including the following:(1) the reaction temperature was altered from ice bath to room temperature;(2) the residence time was reduced by 10 times;(3) the yield was greatly improved, that is, several arylboronates were successfully obtained with higher yield compared to traditional batch process. Therefore, it can be envisioned that a novel, simplified flow synthetic protocol will be developed toward green organic synthesis via MFCs.展开更多
Accurate single-cell capture is a crucial step for single cell biological and chemical analysis. Conventional single-cell capturing often confront operational complexity, limited efficiency, cell damage, large scale b...Accurate single-cell capture is a crucial step for single cell biological and chemical analysis. Conventional single-cell capturing often confront operational complexity, limited efficiency, cell damage, large scale but low accuracy, incompetence in the acquirement of nano-upgraded single-cell liquid. Flow cytometry has been widely used in large-scale single-cell detection, while precise single-cell isolation relies on both a precision operating platform and a microscope, which is not only extremely inefficient, but also not conducive to couple with modern analytical instruments. Herein, we develop a modular single-cell pipette(m SCP) microfluidic chip with high efficiency and strong applicability for accurate direct capture of single viable cell from cell suspensions into nanoliter droplets(30-1000 n L). The m SCP is used as a sampling platform for the detection of Cd Te quantum dots in single cells with electrothermal atomic absorption spectrometry(ETAAS) for the first time. It also ensures precise single-cell sampling and detection by inductively coupled plasma mass spectrometry(ICP-MS).展开更多
Endothelial cells arranged on the vessel lumen are constantly stimulated by blood flow,blood pressure and pressureinduced cyclic stretch.These stimuli are sensed through mechanical sensory structures and converted int...Endothelial cells arranged on the vessel lumen are constantly stimulated by blood flow,blood pressure and pressureinduced cyclic stretch.These stimuli are sensed through mechanical sensory structures and converted into a series of functional responses through mechanotransduction pathways.The process will eventually affect vascular health.Therefore,there has been an urgent need to establish in vitro endothelial biomechanics and mechanobiology of models,which reproduce three-dimensional structure vascular system.In recent years,the rapid development in microfluidic technology makes it possible to replicate the key structural and functionally biomechanical characteristics of vessels.Here,we summarized the progress of microfluidic chips used for the investigation of endothelial biomechanics and mechanobiology of the vascular system.Firstly,we elucidated the contribution of shear stress and circumferential stress,to vascular physiology.Then,we reviewed some applications using microfluidic technology in angiogenesis and vasculogenesis,endothelial permeability and mechanotransduction,as well as the blood-brain barrier under these physical forces.Finally,we discussed the future obstacles in terms of the development and application of microfluidic vascular chips.展开更多
Background:Early diagnosis and classification of infections increase the cure rate while decreasing complications,which is significant for severe infections,especially for war surgery.However,traditional methods rely ...Background:Early diagnosis and classification of infections increase the cure rate while decreasing complications,which is significant for severe infections,especially for war surgery.However,traditional methods rely on laborious operations and bulky devices.On the other hand,point-of-care(POC)methods suffer from limited robustness and accuracy.Therefore,it is of urgent demand to develop POC devices for rapid and accurate diagnosis of infections to fulfill on-site militarized requirements.Methods:We developed a wave-shaped microfluidic chip(WMC)assisted multiplexed detection platform(WMC-MDP).WMC-MDP reduces detection time and improves repeatability through premixing of the samples and reaction of the reagents.We further combined the detection platform with the streptavidin–biotin(SA-B)amplified system to enhance the sensitivity while using chemiluminescence(CL)intensity as signal readout.We realized simultaneous detection of C-reactive protein(CRP),procalcitonin(PCT),and interleukin-6(IL-6)on the detection platform and evaluated the sensitivity,linear range,selectivity,and repeatability.Finally,we finished detecting 15 samples from volunteers and compared the results with commercial ELISA kits.Results:Detection of CRP,PCT,and IL-6 exhibited good linear relationships between CL intensities and concentrations in the range of 1.25–40μg/ml,0.4–12.8 ng/ml,and 50–1600 pg/ml,respectively.The limit of detection of CRP,PCT,and IL-6 were 0.54μg/ml,0.11 ng/ml,and 16.25 pg/ml,respectively.WMC-MDP is capable of good adequate selectivity and repeatability.The whole detection procedure takes only 22 min that meets the requirements of a POC device.Results of 15 samples from volunteers were consistent with the results detected by commercial ELISA kits.Conclusions:WMC-MDP allows simultaneous,rapid,and sensitive detection of CRP,PCT,and IL-6 with satisfactory selectivity and repeatability,requiring minimal manipulation.However,WMC-MDP takes advantage of being a microfluidic device showing the coefficients of variation less than 10%enabling WMC-MDP to be a type of point-of-care testing(POCT).Therefore,WMC-MDP provides a promising alternative to POCT of multiple biomarkers.We believe the practical application of WMC-MDP in militarized fields will revolutionize infection diagnosis for soldiers.展开更多
EGFR mutations companion diagnostics have been proved to be crucial for the efficacy of tyrosine kinase inhibitor targeted cancer therapies. To uncover multiple mutations occurred in minority of EGFR-mutated cells,whi...EGFR mutations companion diagnostics have been proved to be crucial for the efficacy of tyrosine kinase inhibitor targeted cancer therapies. To uncover multiple mutations occurred in minority of EGFR-mutated cells,which may be covered by the noises from majority of unmutated cells, is currently becoming an urgent clinical requirement. Here we present the validation of a microfluidic-chip-based method for detecting EGFR multimutations at single-cell level. By trapping and immunofluorescently imaging single cells in specifically designed silicon microwells, the EGFR-expressed cellswere easily identified. By in situ lysing single cells, the cell lysates of EGFR-expressed cells were retrieved without cross-contamination. Benefited from excluding the noise from cells without EGFR expression, the simple and cost-effective Sanger's sequencing, but not the expensive deep sequencing of the whole cell population, was used to discover multi-mutations. We verified the new method with precisely discovering three most important EGFR drugrelated mutations from a sample in which EGFR-mutated cells only account for a small percentage of whole cell population. The microfluidic chip is capable of discovering not only the existence of specific EGFR multi-mutations,but also other valuable single-cell-level information: on which specific cells the mutations occurred, or whether different mutations coexist on the same cells. This microfluidic chip constitutes a promising method to promote simple and cost-effective Sanger's sequencing to be a routine test before performing targeted cancer therapy.展开更多
creening of foodborne pathogens is important to prevent contaminated foods from their supply chains.n this study, a portable detection device was developed for rapid, sensitive and simple detection of viable almonella...creening of foodborne pathogens is important to prevent contaminated foods from their supply chains.n this study, a portable detection device was developed for rapid, sensitive and simple detection of viable almonella using a finger-actuated microfluidic chip and an improved recombinase aided amplification (RAA) assay. Improved propidium monoazide(PMAxx) was combined with RAA to enable this device to distinguish viable bacteria from dead ones. The modification of PMAxx into dead bacteria, the magnetic xtraction of nucleic acids from viable bacteria and the RAA detection of extracted nucleic acids were performed using the microfluidic chip on its supporting device by finger press-release operations. The fluorescent signal resulting from RAA amplification of the nucleic acids was collected using a USB camera nd analyzed using a self-developed smartphone App to quantitatively determine the bacterial concenration. This device could detect Salmonella typhimurium in spiked chicken meats from 1.3 × 10^(2) CFU/m L o 1.3 × 10^(7) CFU/m L in 2 h with a lower detection limit of 130 CFU/m L, and has shown its potential for on-site detection of foodborne pathogens.展开更多
The rise of antibiotic resistance as one of the most serious global public health threats has necessitated the timely clinical diagnosis and precise treatment of deadly bacterial infections.To identify which types and...The rise of antibiotic resistance as one of the most serious global public health threats has necessitated the timely clinical diagnosis and precise treatment of deadly bacterial infections.To identify which types and doses of antibiotics remain effective for fighting against multi-drug-resistant pathogens,the development of rapid and accurate antibiotic-susceptibility testing(AST)is of primary importance.Conventional methods for AST in well-plate formats with disk diffusion or broth dilution are both labor-intensive and operationally tedious.The microfluidic chip provides a versatile tool for evaluating bacterial AST and resistant behaviors.In this paper,we develop an operationally simple,3D-printed microfluidic chip for AST which automatically deploys antibiotic concentration gradients and fluorescence intensity-based reporting to ideally reduce the report time for AST to within 5 h.By harnessing a commercially available,digital light processing(DLP)3D printing method that offers a rapid,high-precision microfluidic chip-manufacturing capability,we design and realize the accurate generation of on-chip antibiotic concentration gradients based on flow resistance and diffusion mechanisms.We further demonstrate the employment of the microfluidic chip for the AST of E.coli to representative clinical antibiotics of three classes:ampicillin,chloramphenicol,and kanamycin.The determined minimum inhibitory concentration values are comparable to those reported by conventional well-plate methods.Our proposed method demonstrates a promising approach for realizing robust,convenient,and automatable AST of clinical bacterial pathogens.展开更多
To solve the problems of long experiment period and difficult measurement in core imbibition experiments,fracture-matrix microfluidic chips of different sizes,boundary conditions and wettability regulated by surface p...To solve the problems of long experiment period and difficult measurement in core imbibition experiments,fracture-matrix microfluidic chips of different sizes,boundary conditions and wettability regulated by surface property modification were designed to research the imbibition mechanisms of oil-water,oil-surfactant solution and oil-WinsorⅢtype surfactant solution.In the oil-water,and oil-wettability modification system imbibition process,oil was replaced from the matrix through Haines jump,the capillary back pressure was the main resistance blocking the flow of oil,the reduction of interfacial tension caused the weakening of Haines jump,reduction of oil discharge rate,and increase of oil recovery.The imbibition of oil-water or oil-surfactant solution with low interfacial tension was a counter-current imbibition process dominated by capillary force,in which all boundaries had similar contribution to imbibition,and the recovery data obtained from this experiment fit well with the classic imbibition scaling equation.The imbibition of oil and Winsor III type surfactant solution was a co-current imbibition process dominated by gravity under super-low interfacial tension,and is essentially the formation and re-balance of neutral microemulsion.The imbibition dynamics obtained from this experiment fit well with the modified imbibition scaling equation.展开更多
Virus identification is a prerequisite not only for the early diagnosis of viral infectious diseases but also for the effective prevention of epidemics.Successful cultivation is the gold standard for identifying a vir...Virus identification is a prerequisite not only for the early diagnosis of viral infectious diseases but also for the effective prevention of epidemics.Successful cultivation is the gold standard for identifying a virus,according to the Koch postulates.However,this requires screening for a permissive cell line,which is traditionally time-,reagent-and labor-intensive.Here,a simple and easy-to-operate microfluidic chip,formed by seeding a variety of cell lines and culturing them in parallel,is reported for use in virus cultivation and virus-permissive host-cell screening.The chip was tested by infection with two known viruses,enterovirus 71(EV71)and influenza virus H1N1.Infection with EV71 and H1N1 caused significant cytopathic effects(CPE)in RD and MDCK cells,respectively,demonstrating that virus cultivation based on this microfluidic cell chip can be used as a substitute for the traditional plate-based culture method and reproduce the typical CPE caused by virus infection.Using this microfluidic cell chip method for virus cultivation could make it possible to identify an emerging virus in a highthroughput,automatic,and unprecedentedly fast way.展开更多
A combined detection system involving simultaneous LIF and contacfless-conductometric measurements at the same place of the microfluidic chip was described. The LIF measurement was designed according to the confocal p...A combined detection system involving simultaneous LIF and contacfless-conductometric measurements at the same place of the microfluidic chip was described. The LIF measurement was designed according to the confocal principle and a moveable contactless-conduetivity detector was used in C^4D. Both measurements were mutually independent and advantageous in analyses of mixtures. Various experimental parameters affecting the response were examined and optimized. The performances were demonstrated by simultaneous detection of Rhodamine B. And the results showed that the combined detection system could be used sensitively and reliably.展开更多
In this work,an automated microfluidic chip that uses negative pressure to sample and analyze solutions with high temporal resolution was developed.The chip has a T-shaped channel for mixing the sample with a fluoresc...In this work,an automated microfluidic chip that uses negative pressure to sample and analyze solutions with high temporal resolution was developed.The chip has a T-shaped channel for mixing the sample with a fluorescent indicator,a flow-focusing channel for generating droplets in oil,and a long storage channel for incubating and detecting the droplets.By monitoring the fluorescence intensity of the droplets,the device could detect changes in solution accurately over time.The chip can generate droplets at frequencies of up to 42 Hz with a mixing ratio of 1:1 and a temporal resolution of 3–6 s.It had excellent linearity in detecting fluorescein solution in the concentration range 1–5μM.This droplet microfluidic chip provides several advantages over traditional methods,including high temporal resolution,stable droplet generation,and faster flow rates.This approach could be applied to monitoring calcium ions with a dynamic range from 102 to 107 nM and a detection limit of 10 nM.展开更多
On-demand droplet sorting is extensively applied for the efficient manipulation and genome-wide analysis of individual cells.However,state-of-the-art microfluidic chips for droplet sorting still suffer from low sortin...On-demand droplet sorting is extensively applied for the efficient manipulation and genome-wide analysis of individual cells.However,state-of-the-art microfluidic chips for droplet sorting still suffer from low sorting speeds,sample loss,and labor-intensive preparation procedures.Here,we demonstrate the development of a novel microfluidic chip that integrates droplet generation,on-demand electrostatic droplet charging,and high-throughput sorting.The charging electrode is a copper wire buried above the nozzle of the microchannel,and the deflecting electrode is the phosphate buffered saline in the microchannel,which greatly simplifies the structure and fabrication process of the chip.Moreover,this chip is capable of high-frequency droplet generation and sorting,with a frequency of 11.757 kHz in the drop state.The chip completes the selective charging process via electrostatic induction during droplet generation.On-demand charged microdroplets can arbitrarilymove to specific exit channels in a three-dimensional(3D)-deflected electric field,which can be controlled according to user requirements,and the flux of droplet deflection is thereby significantly enhanced.Furthermore,a lossless modification strategy is presented to improve the accuracy of droplet deflection or harvest rate from 97.49% to 99.38% by monitoring the frequency of droplet generation in real time and feeding it back to the charging signal.This chip has great potential for quantitative processing and analysis of single cells for elucidating cell-to-cell variations.展开更多
Surface-enhanced Raman scattering(SERS),owing to its high sensitivity based on localized surface plasmon resonance of nanostructured metals,is recently attracting much attention to be used for biotechnology,such as ce...Surface-enhanced Raman scattering(SERS),owing to its high sensitivity based on localized surface plasmon resonance of nanostructured metals,is recently attracting much attention to be used for biotechnology,such as cell imaging and tumor therapy.On the other hand,the trace detection of bio-molecules with large molecular weight is still challenging because the troublesome treatment of SERS substrate using coupling or cross-linking agents is required.In this paper,we apply liquid interface assisted SERS(LI-SERS)method,which provides unique features of collection and self-immobilization of analyte molecules on the SERS substrate,to realize the label-free trace detection of bio-molecules with detection limits of pM~fM.Specifically,deoxyribonucleic acid(DNA)discrimination and quantitative detection ofβ-Amyloid(Aβ)in trace-concentration are demonstrated to illustrate the ultrahigh sensitivity and versatility of the LI-SERS method.The results suggest LI-SERS is promising for the early-stage diagnosis of diseases such as virus infection and Alzheimer's disease.展开更多
Organs-on-chips composed of a porous membrane-separated,double-layered channels are used widely in elucidating the effects of cell co-culture and flow shear on biological functions.While the diversity of channel geome...Organs-on-chips composed of a porous membrane-separated,double-layered channels are used widely in elucidating the effects of cell co-culture and flow shear on biological functions.While the diversity of channel geometry and membrane permeability is applied,their quantitative correlation with flow features is still unclear.Immersed boundary methods(IBM)simulations and theoretical modelling were performed in this study.Numerical simulations showed that channel length,height and membrane permeability jointly regulated the flow features of flux,penetration velocity and wall shear stress(WSS).Increase of channel length,lower channel height or membrane permeability monotonically reduced the flow flux,velocity and WSS in upper channel before reaching a plateau.While the flow flux in lower channel monotonically increased with the increase of each factor,the WSS surprisingly exhibited a biphasic pattern with first increase and then decrease with increase of lower channel height.Moreover,the transition threshold of maximum WSS was sensitive to the channel length and membrane permeability.Theoretical modeling,integrating the transmembrane pressure difference and inlet flow flux with chip geometry and membrane permeability,was in good agreement with IBM simulations.These analyses provided theoretical bases for optimizing flow-specified chip design and evaluating flow microenvironments of in vivo tissue.展开更多
Concentration gradient and fluid shear stress(FSS)for cell microenvironment were investigated through microfluidic technology.The Darcy–Weisbach equation combined with computational fluid dynamics modeling was exploi...Concentration gradient and fluid shear stress(FSS)for cell microenvironment were investigated through microfluidic technology.The Darcy–Weisbach equation combined with computational fluid dynamics modeling was exploited to design the microfluidic chip,and the FSS distribution on the cell model with varying micro-channels(triangular,conical,and elliptical).The diffusion with the incompressible laminar flow model by solving the time-dependent diffusion–convection equation was applied to simulate the gradient profiles of concentration in the micro-channels.For the study of single cell in-depth,the FSS was investigated by the usage of polystyrene particles and the concentration diffusion distribution was studied by the usage of different colors of dyes.A successful agreement between model simulations and experimental data was obtained.Finally,based on the established method,the communication between individual cells was envisaged and modeled.The developed method provides valuable insights and allows to continuously improve the design of microfluidic devices for the study of single cell,the occurrence and development of tumors,and therapeutic applications.展开更多
基金supported by grants from the Liaoning Province Excellent Talent Program Project(XLYC1902031)Dalian Science and Technology Talent Innovation Plan Grant(2022RG18)Basic Research Project of the Department of Education of Liaoning Province(LJKQZ20222395)。
文摘Objective Cerebral palsy(CP)is a prevalent neurodevelopmental disorder acquired during the perinatal period,with periventricular white matter injury(PWMI)serving as its primary pathological hallmark.PWMI is characterized by the loss of oligodendrocytes(OLs)and the disintegration of myelin sheaths,leading to impaired neural connectivity and motor dysfunction.Neural stem cells(NSCs)represent a promising regenerative source for replenishing lost OLs;however,conventional twodimensional(2D)in vitro culture systems lack the three-dimensional(3D)physiological microenvironment.Microfluidic chip technology has emerged as a powerful tool to overcome this limitation by enabling precise spatial and temporal control over 3D microenvironmental conditions,including the establishment of stable concentration gradients of bioactive molecules.Catalpol,an iridoid glycoside derived from traditional medicinal plants,exhibits dual antioxidant and anti-apoptotic properties.Despite its therapeutic potential,the capacity of catalpol to drive NSC differentiation toward OLs under biomimetic 3D conditions,as well as the underlying molecular mechanisms,remains poorly understood.This study aims to develop a microfluidic-based 3D biomimetic platform to systematically investigate the concentration-dependent effects of catalpol on promoting NSCs-to-OLs differentiation and to elucidate the role of the caveolin-1(Cav-1)signaling pathway in this process.Methods We developed a novel multiplexed microfluidic device featuring parallel microchannels with integrated gradient generators capable of establishing and maintaining precise linear concentration gradients(0-3 g/L catalpol)across 3D NSCs cultures.This platform facilitated the continuous perfusion culture of NSC-derived 3D spheroids,mimicking the dynamic in vivo microenvironment.Real-time cell viability was assessed using Calcein-AM/propidium iodide(PI)dual staining,with fluorescence imaging quantifying live/dead cell ratios.Oligodendrocyte differentiation was evaluated through quantitative reverse transcription polymerase chain reaction(qRT-PCR)for MBP and SOX10 gene expression,complemented by immunofluorescence staining to visualize corresponding protein changes.To dissect the molecular mechanism,the Cav-1-specific pharmacological inhibitor methyl‑β‑cyclodextrin(MCD)was employed to perturb the pathway,and its effects on differentiation markers were analyzed.Results Catalpol demonstrated excellent biocompatibility,with cell viability exceeding 96%across the entire tested concentration range(0-3 g/L),confirming its non-cytotoxic nature.At the optimal concentration of 0-3 g/L,catalpol significantly upregulated both MBP and SOX10 expression(P<0.05,P<0.01),indicating robust promotion of oligodendroglial differentiation.Intriguingly,Cav-1 mRNA expression was progressively downregulated during NSC differentiation into OLs.Further inhibition of Cav-1 with MCD further enhanced this effect,leading to a statistically significant increase in OL-specific gene expression(P<0.05,P<0.01),suggesting Cav-1 acts as a negative regulator of OLs differentiation.Conclusion This study established an integrated microfluidic gradient chip-3D NSC spheroid culture system,which combines the advantages of precise chemical gradient control with physiologically relevant 3D cell culture.The findings demonstrate that 3 g/L catalpol effectively suppresses Cav-1 signaling to drive NSC differentiation into functional OLs.This work not only provides novel insights into the Cav-1-dependent mechanisms of myelination but also delivers a scalable technological platform for future research on remyelination therapies,with potential applications in cerebral palsy and other white matter disorders.The platform’s modular design permits adaptation for screening other neurogenic compounds or investigating additional signaling pathways involved in OLs maturation.
文摘Multi-layer microbubble has great potential in enabling the corporation of medical imaging with tumor therapy such as drug and gene delivery of therapeutics or other functional materials in medical applications. Microfluidic technique has advanced over the last decade and showed great promise in replacing traditional microbubble generating method. In this paper, a multi-layer microbubble structure was produced with the aspect as potentially used for drug loaded microbubble contrast agents.
基金financial support from the National Natural Science Foundation of China(No.81673398)
文摘The development of pharmaceutical analytical methods represents one of the most significant aspects of drug development. Recent advances in microfabrication and microfluidics could provide new approaches for drug analysis, including drug screening, active testing and the study of metabolism. Microfluidic chip technologies, such as lab-on-a-chip technology, three-dimensional (3D) cell culture, organs-on-chip and droplet techniques, have all been developed rapidly. Microfluidic chips coupled with various kinds of detection techniques are suitable for the high-throughput screening, detection and mechanistic study of drugs. This review highlights the latest (2010–2018) microfluidic technology for drug analysis and discusses the potential future development in this field.
基金supported by the National Natural Science Foundation of China(Nos.21727814,21435002 and 21621003)。
文摘In this work,a multi-functional analysis platform by coupling a microfluidic chip to a mass spectrometry(MS) detector was described.We constructed a three-dimensional tumor-endothelial co-culture model for simulating drug resistance during tumor treatment.On this specially designed integrated platform,the first step was to prepare heterogeneous cell-encapsulated alginate microcapsules for threedimensional co-culture,and the second step was to achieve on-line perfusion culture and continuous drug stimulation on chip.It facilitates cell proliferation analysis and the collection of metabolism medium.After micro solid phase extraction column(SPE) pretreatment,subsequent mass spectrometry could detect drug metabolism.The high activity of two kinds of cells(A549 and HUVEC) shows the biocompatibility of the platform.Paclitaxel was used as a model drug,the distinctions of drug absorption between the mono-culture group and co-culture group were clearly observed by electrospray ionization quadrupole time-of-flight mass spectrometry(ESI-Q-TOF MS).Therefore,the integrated platform has shown promise as a high throughput,low cost for cell metabolism research and drug screening processes.
基金National Hi-tech Research Development Program of China(863 Program,No.2002AA421150)Research Foundation of Doctorial Project of Ministry of Education,China(No.20030335091)
文摘Experiments are used to study the fabrication of polymer microfluidic chip with hot embossing method. The pattern fidelity with respect to the process parameters is analyzed. Experiment results show that the relationship between the imprint temperature and the microchannel width is approximately exponential. However, the depth of micro channel isn＇t sensitive to the imprint temperature. When the imprint pressure is larger than 1 MPa and the imprint time is longer than 2 min, the increasing of imprint pressure and holding time has little impact on the microchannel width. So over long holding time is not needed in hot embossing. Based on the experiment analysis, a series of optimization process parameters is obtained and a fine microfluidic chip is fabricated. The electrophoresis separation experiment are used to verify the microfluidic chip performance after bonding. The results show that 100bp-ladder DNA sample can be separated in less than 5 min successfully.
基金supported by the Shanghai Municipal Science and Technology Major Project (“Beyond Limits manufacture”)。
文摘The first example of the microfluidic chips(MFCs) consisting of centimeter-level 3D channels with highdensity and large-volume fabricated by femtosecond laser micromachining were utilized to develop a time-saving, economical and hazardless flow synthesis process, and its advantages have been proved by in situ formation of aryldiazonium salts and subsequent borylation with bis(pinacolato)diboron. There are several important advantages in our 3D MFC-based flow synthesis technology, including the following:(1) the reaction temperature was altered from ice bath to room temperature;(2) the residence time was reduced by 10 times;(3) the yield was greatly improved, that is, several arylboronates were successfully obtained with higher yield compared to traditional batch process. Therefore, it can be envisioned that a novel, simplified flow synthetic protocol will be developed toward green organic synthesis via MFCs.
基金financial support of the National Natural Science Foundation of China (Nos. 21727811,21922402)the Fundamental Research Funds for the Central Universities (Nos. N2005003, N2105017)+1 种基金the Liaoning Revitalization Talents Program (No. XLYC1802016)Scientific Research Funding Project of the Education Department of Liaoning (No. LJKZ0007)。
文摘Accurate single-cell capture is a crucial step for single cell biological and chemical analysis. Conventional single-cell capturing often confront operational complexity, limited efficiency, cell damage, large scale but low accuracy, incompetence in the acquirement of nano-upgraded single-cell liquid. Flow cytometry has been widely used in large-scale single-cell detection, while precise single-cell isolation relies on both a precision operating platform and a microscope, which is not only extremely inefficient, but also not conducive to couple with modern analytical instruments. Herein, we develop a modular single-cell pipette(m SCP) microfluidic chip with high efficiency and strong applicability for accurate direct capture of single viable cell from cell suspensions into nanoliter droplets(30-1000 n L). The m SCP is used as a sampling platform for the detection of Cd Te quantum dots in single cells with electrothermal atomic absorption spectrometry(ETAAS) for the first time. It also ensures precise single-cell sampling and detection by inductively coupled plasma mass spectrometry(ICP-MS).
基金supported by the National Natural Science Research Foundation of China(61533016,11827803,31971244,31570947,11772036,11421202 and U20A20390)the National Key Research and Development Program of China(2016YFC1102202 and 2016YFC1101101)Beijing Natural Science Foundation(4194079)and the 111 Project(B13003).
文摘Endothelial cells arranged on the vessel lumen are constantly stimulated by blood flow,blood pressure and pressureinduced cyclic stretch.These stimuli are sensed through mechanical sensory structures and converted into a series of functional responses through mechanotransduction pathways.The process will eventually affect vascular health.Therefore,there has been an urgent need to establish in vitro endothelial biomechanics and mechanobiology of models,which reproduce three-dimensional structure vascular system.In recent years,the rapid development in microfluidic technology makes it possible to replicate the key structural and functionally biomechanical characteristics of vessels.Here,we summarized the progress of microfluidic chips used for the investigation of endothelial biomechanics and mechanobiology of the vascular system.Firstly,we elucidated the contribution of shear stress and circumferential stress,to vascular physiology.Then,we reviewed some applications using microfluidic technology in angiogenesis and vasculogenesis,endothelial permeability and mechanotransduction,as well as the blood-brain barrier under these physical forces.Finally,we discussed the future obstacles in terms of the development and application of microfluidic vascular chips.
基金the National Natural Science Foundation of China(81902167,52075138)the Natural Science Foundation of Jiangsu Province(BK20190872).
文摘Background:Early diagnosis and classification of infections increase the cure rate while decreasing complications,which is significant for severe infections,especially for war surgery.However,traditional methods rely on laborious operations and bulky devices.On the other hand,point-of-care(POC)methods suffer from limited robustness and accuracy.Therefore,it is of urgent demand to develop POC devices for rapid and accurate diagnosis of infections to fulfill on-site militarized requirements.Methods:We developed a wave-shaped microfluidic chip(WMC)assisted multiplexed detection platform(WMC-MDP).WMC-MDP reduces detection time and improves repeatability through premixing of the samples and reaction of the reagents.We further combined the detection platform with the streptavidin–biotin(SA-B)amplified system to enhance the sensitivity while using chemiluminescence(CL)intensity as signal readout.We realized simultaneous detection of C-reactive protein(CRP),procalcitonin(PCT),and interleukin-6(IL-6)on the detection platform and evaluated the sensitivity,linear range,selectivity,and repeatability.Finally,we finished detecting 15 samples from volunteers and compared the results with commercial ELISA kits.Results:Detection of CRP,PCT,and IL-6 exhibited good linear relationships between CL intensities and concentrations in the range of 1.25–40μg/ml,0.4–12.8 ng/ml,and 50–1600 pg/ml,respectively.The limit of detection of CRP,PCT,and IL-6 were 0.54μg/ml,0.11 ng/ml,and 16.25 pg/ml,respectively.WMC-MDP is capable of good adequate selectivity and repeatability.The whole detection procedure takes only 22 min that meets the requirements of a POC device.Results of 15 samples from volunteers were consistent with the results detected by commercial ELISA kits.Conclusions:WMC-MDP allows simultaneous,rapid,and sensitive detection of CRP,PCT,and IL-6 with satisfactory selectivity and repeatability,requiring minimal manipulation.However,WMC-MDP takes advantage of being a microfluidic device showing the coefficients of variation less than 10%enabling WMC-MDP to be a type of point-of-care testing(POCT).Therefore,WMC-MDP provides a promising alternative to POCT of multiple biomarkers.We believe the practical application of WMC-MDP in militarized fields will revolutionize infection diagnosis for soldiers.
基金supported by the National HighTech R&D Program of China(No.2015AA020408)National Natural Science Foundation of China(No.61204118,81500900 and21503054)+1 种基金Beijing Municipal Science and Technology Project(No.Z171100002017013)Key Research Program of the Chinese Academy of Sciences,Grant NO.KFZD-SW-210
文摘EGFR mutations companion diagnostics have been proved to be crucial for the efficacy of tyrosine kinase inhibitor targeted cancer therapies. To uncover multiple mutations occurred in minority of EGFR-mutated cells,which may be covered by the noises from majority of unmutated cells, is currently becoming an urgent clinical requirement. Here we present the validation of a microfluidic-chip-based method for detecting EGFR multimutations at single-cell level. By trapping and immunofluorescently imaging single cells in specifically designed silicon microwells, the EGFR-expressed cellswere easily identified. By in situ lysing single cells, the cell lysates of EGFR-expressed cells were retrieved without cross-contamination. Benefited from excluding the noise from cells without EGFR expression, the simple and cost-effective Sanger's sequencing, but not the expensive deep sequencing of the whole cell population, was used to discover multi-mutations. We verified the new method with precisely discovering three most important EGFR drugrelated mutations from a sample in which EGFR-mutated cells only account for a small percentage of whole cell population. The microfluidic chip is capable of discovering not only the existence of specific EGFR multi-mutations,but also other valuable single-cell-level information: on which specific cells the mutations occurred, or whether different mutations coexist on the same cells. This microfluidic chip constitutes a promising method to promote simple and cost-effective Sanger's sequencing to be a routine test before performing targeted cancer therapy.
基金funded by National Natural Science Foundation of China (No. 32071899)Walmart Foundation (No. UA2020– 154)。
文摘creening of foodborne pathogens is important to prevent contaminated foods from their supply chains.n this study, a portable detection device was developed for rapid, sensitive and simple detection of viable almonella using a finger-actuated microfluidic chip and an improved recombinase aided amplification (RAA) assay. Improved propidium monoazide(PMAxx) was combined with RAA to enable this device to distinguish viable bacteria from dead ones. The modification of PMAxx into dead bacteria, the magnetic xtraction of nucleic acids from viable bacteria and the RAA detection of extracted nucleic acids were performed using the microfluidic chip on its supporting device by finger press-release operations. The fluorescent signal resulting from RAA amplification of the nucleic acids was collected using a USB camera nd analyzed using a self-developed smartphone App to quantitatively determine the bacterial concenration. This device could detect Salmonella typhimurium in spiked chicken meats from 1.3 × 10^(2) CFU/m L o 1.3 × 10^(7) CFU/m L in 2 h with a lower detection limit of 130 CFU/m L, and has shown its potential for on-site detection of foodborne pathogens.
基金the National Natural Science Foundation of China(No.51908467)and by institutional funds from the Westlake University。
文摘The rise of antibiotic resistance as one of the most serious global public health threats has necessitated the timely clinical diagnosis and precise treatment of deadly bacterial infections.To identify which types and doses of antibiotics remain effective for fighting against multi-drug-resistant pathogens,the development of rapid and accurate antibiotic-susceptibility testing(AST)is of primary importance.Conventional methods for AST in well-plate formats with disk diffusion or broth dilution are both labor-intensive and operationally tedious.The microfluidic chip provides a versatile tool for evaluating bacterial AST and resistant behaviors.In this paper,we develop an operationally simple,3D-printed microfluidic chip for AST which automatically deploys antibiotic concentration gradients and fluorescence intensity-based reporting to ideally reduce the report time for AST to within 5 h.By harnessing a commercially available,digital light processing(DLP)3D printing method that offers a rapid,high-precision microfluidic chip-manufacturing capability,we design and realize the accurate generation of on-chip antibiotic concentration gradients based on flow resistance and diffusion mechanisms.We further demonstrate the employment of the microfluidic chip for the AST of E.coli to representative clinical antibiotics of three classes:ampicillin,chloramphenicol,and kanamycin.The determined minimum inhibitory concentration values are comparable to those reported by conventional well-plate methods.Our proposed method demonstrates a promising approach for realizing robust,convenient,and automatable AST of clinical bacterial pathogens.
基金Supported by the China National Science and Technology Major Project(2017ZX05009-005-003)the Strategic Consulting Project of Chinese Academy of Engineering(2018-XZ-09)the Science Foundation of China University of Petroleum,Beijing(No.2462019QNXZ04)。
文摘To solve the problems of long experiment period and difficult measurement in core imbibition experiments,fracture-matrix microfluidic chips of different sizes,boundary conditions and wettability regulated by surface property modification were designed to research the imbibition mechanisms of oil-water,oil-surfactant solution and oil-WinsorⅢtype surfactant solution.In the oil-water,and oil-wettability modification system imbibition process,oil was replaced from the matrix through Haines jump,the capillary back pressure was the main resistance blocking the flow of oil,the reduction of interfacial tension caused the weakening of Haines jump,reduction of oil discharge rate,and increase of oil recovery.The imbibition of oil-water or oil-surfactant solution with low interfacial tension was a counter-current imbibition process dominated by capillary force,in which all boundaries had similar contribution to imbibition,and the recovery data obtained from this experiment fit well with the classic imbibition scaling equation.The imbibition of oil and Winsor III type surfactant solution was a co-current imbibition process dominated by gravity under super-low interfacial tension,and is essentially the formation and re-balance of neutral microemulsion.The imbibition dynamics obtained from this experiment fit well with the modified imbibition scaling equation.
基金the Scientific Instrument Developing Project of the Chinese Academy of Sciences(No.YJKYYQ20190057)the National Nature Science Foundation of China(No.81827804)+1 种基金the CAS Emergency Project of ASF Research(No.KJZDSW-L06-02)Applied Basic Research Program of Wuhan(No.2018060401011327)。
文摘Virus identification is a prerequisite not only for the early diagnosis of viral infectious diseases but also for the effective prevention of epidemics.Successful cultivation is the gold standard for identifying a virus,according to the Koch postulates.However,this requires screening for a permissive cell line,which is traditionally time-,reagent-and labor-intensive.Here,a simple and easy-to-operate microfluidic chip,formed by seeding a variety of cell lines and culturing them in parallel,is reported for use in virus cultivation and virus-permissive host-cell screening.The chip was tested by infection with two known viruses,enterovirus 71(EV71)and influenza virus H1N1.Infection with EV71 and H1N1 caused significant cytopathic effects(CPE)in RD and MDCK cells,respectively,demonstrating that virus cultivation based on this microfluidic cell chip can be used as a substitute for the traditional plate-based culture method and reproduce the typical CPE caused by virus infection.Using this microfluidic cell chip method for virus cultivation could make it possible to identify an emerging virus in a highthroughput,automatic,and unprecedentedly fast way.
文摘A combined detection system involving simultaneous LIF and contacfless-conductometric measurements at the same place of the microfluidic chip was described. The LIF measurement was designed according to the confocal principle and a moveable contactless-conduetivity detector was used in C^4D. Both measurements were mutually independent and advantageous in analyses of mixtures. Various experimental parameters affecting the response were examined and optimized. The performances were demonstrated by simultaneous detection of Rhodamine B. And the results showed that the combined detection system could be used sensitively and reliably.
基金We acknowledge support from the equipment research and development projects of the Chinese Academy of Sciences,“On-chip integrated optical biochemical detection key technology research and development team,”E11YTB1001.
文摘In this work,an automated microfluidic chip that uses negative pressure to sample and analyze solutions with high temporal resolution was developed.The chip has a T-shaped channel for mixing the sample with a fluorescent indicator,a flow-focusing channel for generating droplets in oil,and a long storage channel for incubating and detecting the droplets.By monitoring the fluorescence intensity of the droplets,the device could detect changes in solution accurately over time.The chip can generate droplets at frequencies of up to 42 Hz with a mixing ratio of 1:1 and a temporal resolution of 3–6 s.It had excellent linearity in detecting fluorescein solution in the concentration range 1–5μM.This droplet microfluidic chip provides several advantages over traditional methods,including high temporal resolution,stable droplet generation,and faster flow rates.This approach could be applied to monitoring calcium ions with a dynamic range from 102 to 107 nM and a detection limit of 10 nM.
基金The authors acknowledge the financial support from the NationalNatural Science Foundation ofChina(No.52275562)the Technology Innovation Fund of Huazhong University of Science and Technology(No.2022JYCXJJ015).
文摘On-demand droplet sorting is extensively applied for the efficient manipulation and genome-wide analysis of individual cells.However,state-of-the-art microfluidic chips for droplet sorting still suffer from low sorting speeds,sample loss,and labor-intensive preparation procedures.Here,we demonstrate the development of a novel microfluidic chip that integrates droplet generation,on-demand electrostatic droplet charging,and high-throughput sorting.The charging electrode is a copper wire buried above the nozzle of the microchannel,and the deflecting electrode is the phosphate buffered saline in the microchannel,which greatly simplifies the structure and fabrication process of the chip.Moreover,this chip is capable of high-frequency droplet generation and sorting,with a frequency of 11.757 kHz in the drop state.The chip completes the selective charging process via electrostatic induction during droplet generation.On-demand charged microdroplets can arbitrarilymove to specific exit channels in a three-dimensional(3D)-deflected electric field,which can be controlled according to user requirements,and the flux of droplet deflection is thereby significantly enhanced.Furthermore,a lossless modification strategy is presented to improve the accuracy of droplet deflection or harvest rate from 97.49% to 99.38% by monitoring the frequency of droplet generation in real time and feeding it back to the charging signal.This chip has great potential for quantitative processing and analysis of single cells for elucidating cell-to-cell variations.
基金the Special Postdoctoral Researcher Program and Incentive Research Project of RIKEN.
文摘Surface-enhanced Raman scattering(SERS),owing to its high sensitivity based on localized surface plasmon resonance of nanostructured metals,is recently attracting much attention to be used for biotechnology,such as cell imaging and tumor therapy.On the other hand,the trace detection of bio-molecules with large molecular weight is still challenging because the troublesome treatment of SERS substrate using coupling or cross-linking agents is required.In this paper,we apply liquid interface assisted SERS(LI-SERS)method,which provides unique features of collection and self-immobilization of analyte molecules on the SERS substrate,to realize the label-free trace detection of bio-molecules with detection limits of pM~fM.Specifically,deoxyribonucleic acid(DNA)discrimination and quantitative detection ofβ-Amyloid(Aβ)in trace-concentration are demonstrated to illustrate the ultrahigh sensitivity and versatility of the LI-SERS method.The results suggest LI-SERS is promising for the early-stage diagnosis of diseases such as virus infection and Alzheimer's disease.
基金supported by the National Natural Science Foundation of China(Grants 91642203,31627804,31661143044,and 31570942)the Frontier Science Key Project of Chinese Science Academy(Grant QYZDJ-SSW-JSC018)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant XDB22040101).
文摘Organs-on-chips composed of a porous membrane-separated,double-layered channels are used widely in elucidating the effects of cell co-culture and flow shear on biological functions.While the diversity of channel geometry and membrane permeability is applied,their quantitative correlation with flow features is still unclear.Immersed boundary methods(IBM)simulations and theoretical modelling were performed in this study.Numerical simulations showed that channel length,height and membrane permeability jointly regulated the flow features of flux,penetration velocity and wall shear stress(WSS).Increase of channel length,lower channel height or membrane permeability monotonically reduced the flow flux,velocity and WSS in upper channel before reaching a plateau.While the flow flux in lower channel monotonically increased with the increase of each factor,the WSS surprisingly exhibited a biphasic pattern with first increase and then decrease with increase of lower channel height.Moreover,the transition threshold of maximum WSS was sensitive to the channel length and membrane permeability.Theoretical modeling,integrating the transmembrane pressure difference and inlet flow flux with chip geometry and membrane permeability,was in good agreement with IBM simulations.These analyses provided theoretical bases for optimizing flow-specified chip design and evaluating flow microenvironments of in vivo tissue.
基金National Natural Science Foundation of China(No.21804045)Fujian Provincial Department of Science and Technology(No.2019I0014)Promotion Program for Young and Middle-aged Teachers in Science and Technology Research of Huaqiao University(No.ZQN-PY612)。
文摘Concentration gradient and fluid shear stress(FSS)for cell microenvironment were investigated through microfluidic technology.The Darcy–Weisbach equation combined with computational fluid dynamics modeling was exploited to design the microfluidic chip,and the FSS distribution on the cell model with varying micro-channels(triangular,conical,and elliptical).The diffusion with the incompressible laminar flow model by solving the time-dependent diffusion–convection equation was applied to simulate the gradient profiles of concentration in the micro-channels.For the study of single cell in-depth,the FSS was investigated by the usage of polystyrene particles and the concentration diffusion distribution was studied by the usage of different colors of dyes.A successful agreement between model simulations and experimental data was obtained.Finally,based on the established method,the communication between individual cells was envisaged and modeled.The developed method provides valuable insights and allows to continuously improve the design of microfluidic devices for the study of single cell,the occurrence and development of tumors,and therapeutic applications.
