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
Microproteomics, the profiling of protein expressions in small cell populations or individual cells, is essential for understanding complex biological systems. However, sample loss and insufficient sensitivity of anal...Microproteomics, the profiling of protein expressions in small cell populations or individual cells, is essential for understanding complex biological systems. However, sample loss and insufficient sensitivity of analytical techniques pose severe challenges to this field. Microfluidics, particularly droplet-based microfluidics, provides an ideal approach by enabling miniaturized and integrated workflows to process samples and offers several advantages, including reduced sample loss, low reagent consumption, faster reaction times, and improved throughput. Droplet-based microfluidics manipulates droplets of fluids to function as discrete reaction units, enabling complex chemical reactions and biological workflows in a miniaturized setting. This article discusses a variety of on-chip functions of droplet-based microfluidics,including cell sorting, cell culture, and sample processing. We then highlight recent advances in the mass spectrometry(MS)-based analysis of single cells using droplet-based microfluidic platforms, including digital microfluidics(DMF). Finally, we review the integrated DMF–MS systems that enable automated and parallel proteomic profiling of single cells with high sensitivity and discuss the applications of the technology and its future perspectives.展开更多
Objective:Sperm preparation techniques and cryopreservation are widely used in assisted reproductive techniques(ART).How to improve the quality of sperm management is a matter of great concern.Phospholipase C-zeta(PLC...Objective:Sperm preparation techniques and cryopreservation are widely used in assisted reproductive techniques(ART).How to improve the quality of sperm management is a matter of great concern.Phospholipase C-zeta(PLCζ)is considered a sperm-specific agent that activates oocyte activation and thus playing a crucial role in male fertility.However,the potential mechanisms by which semen processing and cryopreservation on PLCζcontribute to keyhole have not been addressed.Methods:In this study,semen samples were taken from have not been addressed 10 normozoospermic men.Each semen sample was assigned to the following groups:density gradient centrifugation(DGC)as control,microfluidic sorting,and cryopreservation.Sperm parameters of molity,viability,membrane integrity,and intracellular ROS were evaluated during sperm preparation and cryopreservation.The expression of PLCζin human sperm was determined by immunofluorescence and western blotting.Results:The results showed that molity,viability,and membrane integrity decreased in cryopreservation group.Intracellular ROS were also significantly increased compared to the the control group.There was no significant difference between DGC and microfluidic sorting group.Our investigation revealed that total levels of PLCζwere comparable between DGC and microfluidic sorting,but there were significantly reduced levels of PLCζafter cryopreservation as quantified by both immunofluorescenceand immunoblotting.PLCζimmunofluorescence in sperm revealed different PLCζlocalization patterns around the acrosomal(Ac),equatorial(Eq),post-acrosomal(PA)areas of sperm heads,and their combination.The predominant patterns of PLCζlocalization in DGC were similar to that of microfluidic sorting,with strong,with staining.In contrast,PLCζstaining in freeze-thawed sperm was considerably weaker fluorescence intensity.Conclusion:This study clarified the mechanism of sperm preparation and cryopreservation underlying effect on sperm characteristic,accompanied with PLCζexpresion.We demonstrated that microfluidic sorting provides a highly efficient preparation method for clinical selection of PLCζ-expressing sperm comparable to DGC gene expression.It is suggested that the cryopreservation of sperm has a significant detrimental effect on PLCζ.展开更多
Droplet microfluidics,which encapsulates individual cells within separate microreactors,has become an essential tool for single-cell phenotypic and genotypic analysis.However,the efficiency of single-cell encapsulatio...Droplet microfluidics,which encapsulates individual cells within separate microreactors,has become an essential tool for single-cell phenotypic and genotypic analysis.However,the efficiency of single-cell encapsulation is limited by the Poisson distribution governing the encapsulation process,resulting in most droplets being either empty or containing multiple cells.Traditional single-cell sorting methods typically rely on fluorescence labeling for identification,but this approach not only increases experimental costs and complexity but can also impact cell viability.Additionally,current label-free sorting methods still encounter difficulties in accurately detecting multicellular droplets and small cellular aggregates.To address these challenges,this paper proposes an intelligent sorting system that combines YOLOv8 object detection and BoTSORT tracking algorithms.This system enables real-time analysis of droplet images,facilitating precise identification,counting,and automated sorting of target droplets.To validate the system’s performance,polystyrene microspheres were used to simulate real cells in sorting tests.The results demonstrated that,under label-free conditions,the system significantly outperformed traditional fluorescence labeling methods in both classification accuracy and sorting efficiency.This system provides an effective,label-free solution for cell sorting,with potential applications in precision medicine,single-cell sequencing,and drug screening.展开更多
Soft rot is a destructive disease that inflicts significant losses on agricultural production and the economy post-harvest.Biocontrol strategies based on antagonistic microorganisms have a broad application prospect t...Soft rot is a destructive disease that inflicts significant losses on agricultural production and the economy post-harvest.Biocontrol strategies based on antagonistic microorganisms have a broad application prospect to fight against plant pathogens.This study utilized fluorescence-activated droplet sorting(FADS)technology as an alternative to traditional plate culture methods to isolate microorganisms with antagonistic activity against the soft rot pathogen Erwinia carotovora Ecc15.Initially,the culture performance of the FADS platform was evaluated by analyzing bacterial diversity in droplet culture samples and agar plate culture samples,our data showed that droplet culture exhibited higher species richness and diversity than plate culture,and more than 95%of the operational taxonomic units(OTUs)in the droplet samples belonged to the rare biosphere.Additionally,we developed a green fluorescent protein(GFP)-Ecc15-based FADS screening system,which achieved an enrichment ratio of up to 148.Using this system,we successfully screened 32 antagonistic bacteria from rhizosphere soil sample of healthy konjac plants,and some may be novel microbial resources,including the genera Lelliottia,Buttiauxella and Leclercia.Notably,strain D-62 exhibited the strongest antibacterial ability against Ecc15,with an inhibition zone diameter of(20.86±1.56)mm.In vivo experiments conducted on the corms of Amorphophallus konjac demonstrated that strain D-62 could effectively reduce the infection ability of Ecc15 to the corms,indicating that strain D-62 has the potential to be developed as a biocontrol agent.Our findings suggested that the FADS screening system showed a screening efficiency approximately 3×10^(3)times higher than plate screening system,while significantly reducing costs of infrastructure,labor and consumables,it provides theoretical guidance for the screening of other plant pathogen biocontrol bacteria.展开更多
Droplet-based microfluidic technology can be utilized as a microreactor to prepare novel functional monodisperse microcapsules.In this study,a droplet-based microfluidic chip with surface modification,which allowed th...Droplet-based microfluidic technology can be utilized as a microreactor to prepare novel functional monodisperse microcapsules.In this study,a droplet-based microfluidic chip with surface modification,which allowed the one-step preparation of double emulsion microcapsules.An O/W/O double emulsion using polyethylene(glycol)diacrylate(PEGDA)solution as the intermediate water phase was prepared by regulating the hydrophilicity and hydrophobicity of the chip surface,with PEGDA microcapsules prepared using UV polymerization.And then anti-tumor drug paclitaxel and neurotoxin 6-OHDA were encapsulated in microcapsules for drug and toxicology evaluation,respectively.Compared to controls,drug-loaded mi-crocapsules caused a significant increase in the death rate of PC12 cells.This indicates that the obtained drug-loaded microcapsules could be used in drug evaluation and potentially in drug screening and deliv-ery.展开更多
The compartimentation of fluids in the microliter, nanoliter and picoliter range leads recently to many applications of microfluidics in material development, diagnostics and biological screenings. Droplet-based micro...The compartimentation of fluids in the microliter, nanoliter and picoliter range leads recently to many applications of microfluidics in material development, diagnostics and biological screenings. Droplet-based microfluidics allows the improvement of nanoparticle homogeneity and the tuning of particle properties. It supports combinatorial synthesis of inorganic as well as organic substances and can be applied for the cultivation and screening of bacteria, eucaryotic cells and fish embryos. The well-ordered handling and the addressing of microfluid segments improves the information transfer between chemical, biological and electronic systems. Despite this remarkable technical progress, there is a particular importance of microfluidics for future nanotechnological solutions. The hierarchical spatial organization of liquids, particles and gels in microfluidics represents a fundamental biomimetic principle which overcomes the limits of planar technology and opens the gate for realizing complex structured threedimensional nanoarchitectures. Recent applications of microstructured fluids in chemistry and biology and concepts for future developments will be discussed.展开更多
The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing in...The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing intensely rely on centrifugation and wash steps that may induce mechanical damage and oxidative stress to sperm.Although a few microfluidic sperm sorting devices may avoid these adverse effects by exploiting intrinsic guidance mechanisms of sperm swimming,none of these approaches have been fully validated by clinical-grade assessment criteria.In this study,a microfluidic sperm sorting device that enables the selection of highly motile and functional sperm via their intrinsic thermotaxis is presented.Bioinspired by the temperature microenvironment in the fallopian tube during natural sperm selection,a microfluidic device with controllable temperature gradients along the sperm separation channel was designed and fabricated.This study investigated the optimal temperature conditions for human sperm selection and fully characterized thermotaxis-selected sperm with 45 human sperm samples.Results indicated that a temperature range of 35–36.5℃along the separation channel significantly improves human sperm motility rate((85.25±6.28)%vs.(60.72±1.37)%;P=0.0484),increases normal sperm morphology rate((16.42±1.43)%vs.(12.55±0.88)%;P<0.0001),and reduces DNA fragmentation((7.44±0.79)%vs.(10.36±0.72)%;P=0.0485)compared to the nonthermotaxis group.Sperm thermotaxis is species-specific,and selected mouse sperm displayed the highest motility in response to a temperature range of 36–37.5℃ along the separation channel.Furthermore,IVF experiments indicated that the selected sperm permitted an increased fertilization rate and improved embryonic development from zygote to blastocyst.This microfluidic thermotaxic selection approach will be translated into clinical practice to improve the IVF success rate for patients with oligozoospermia and asthenozoospermia.展开更多
This numerical study proposes a cell sorting technique based on dielectrophoresis(DEP)in a microfluidic chip.Under the joint effect of DEP and fluid drag,white blood cells and circulating tumor cells are separated be...This numerical study proposes a cell sorting technique based on dielectrophoresis(DEP)in a microfluidic chip.Under the joint effect of DEP and fluid drag,white blood cells and circulating tumor cells are separated because of different dielectric properties.First,the mathematical models of device geometry,single cell,DEP force,electric field,and flow field are established to simulate the cell motion.Based on the simulation model,important boundary parameters are discussed to optimize the cell sorting ability of the device.A proper matching relationship between voltage and flow rate is then provided.The inlet and outlet conditions are also investigated to control the particle motion in the flow field.The significance of this study is to verify the cell separating ability of the microfluidic chip,and to provide a logistic design for the separation of rare diseased cells.展开更多
Circulating tumor cells(CTCs)are essential biomarkers for liquid biopsies,which are important in the early screening,prognosis,and real-time monitoring of cancer.However,CTCs are less abundant in the peripheral blood ...Circulating tumor cells(CTCs)are essential biomarkers for liquid biopsies,which are important in the early screening,prognosis,and real-time monitoring of cancer.However,CTCs are less abundant in the peripheral blood of patients,therefore,their isolation is necessary.Recently,the use of microfluidics for CTC sorting has become a research hotspot owing to its low cost,ease of integration,low sample consumption,and unique advantages in the manipulation of micron-sized particles.Herein,we review the latest research on microfluidics-based CTC sorting.Specifically,we consider active sorting using external fields(electric,magnetic,acoustic,and optical tweezers)and passive sorting using the flow effects of cells in specific channel structures(microfiltration sorting,deterministic lateral displacement sorting,and inertial sorting).The advantages and limitations of each method and their recent applications are summarized here.To conclude,a forward-looking perspective is presented on future research on the microfluidic sorting of CTCs.展开更多
Lead halide perovskite nanocrystals(NCs)exhibit high photoluminescence quantum yield(PLQY),high defect tolerance,narrow half peak width,and wide luminous gamut,making them the ideal optoelectronic materials in numerou...Lead halide perovskite nanocrystals(NCs)exhibit high photoluminescence quantum yield(PLQY),high defect tolerance,narrow half peak width,and wide luminous gamut,making them the ideal optoelectronic materials in numerous fields.Nonetheless,their production still suffers from the limited productivity at the bench level.In this work,we fabricated CsPbX3(X=Cl,Br,I)NCs within droplet-based micro-reactors,where both the nucleation and growth processes could be precisely controlled inside 130-nL microdroplets.This provides a new paradigm for the large-scale synthesis of perovskite NCs with high PLQY.Compared with other synthetic methods,this method can increase the concentration of reactant precursors by 3±116 times,while lowering the ligand to reactant ratio to 2%±50%of the commonly used hot-injection method.By modulating the reaction temperature and residence time,the structure-function relationship between the morphology of NCs and PL properties was extensively investigated.The microfluidic-based process allows the flexible adjustment in the proportion of PbX2 precursors to achieve the fabrication of perovskite NCs whose luminescence range covers the entire visible spectrum(406±677 nm)within one reaction.Finally,perovskite NCs with different halide ions were encapsulated in polymethyl methacrylate to prepare a colored light-emitting diode strip.展开更多
Sorting high-quality sperm with intact DNA,normal morphology,and active motility is crucial for clinically assisted reproductive technology,which influences the success of treatment and the health of offspring.Current...Sorting high-quality sperm with intact DNA,normal morphology,and active motility is crucial for clinically assisted reproductive technology,which influences the success of treatment and the health of offspring.Currently,microfluidic technology has been developed as a powerful platform for sperm sorting owing to its ability to manipulate fluid at the microscale and handle small samples.Specifically,microfluidic technology provides the necessary stimuli including fluid stimulus,chemical induction,and shape sift,which supports researchers in developing various sperm-sorting devices.According to the sorting principle,these devices can be divided into three categories:active sorting devices based on sperm rheological properties,passive sorting devices based on sperm physical properties,and external stimuli-induced sorting devices.Hence,we review a broad range of researches about sperm sorting with microfluidics and briefly present the properties of sperm and female reproductive tract to assist the design of microfluidic sperm sorting devices.展开更多
Flow cytometry is a powerful technique for rapidly analyzing the physical and biological characteristics of small biological particles,such as cells,as well as sorting specific targets.This capability has made it indi...Flow cytometry is a powerful technique for rapidly analyzing the physical and biological characteristics of small biological particles,such as cells,as well as sorting specific targets.This capability has made it indispensable in a range of biological fields,including cell sequencing,drug development,medical diagnosis,and environmental monitoring.Over the past few decades,these areas have been revolutionized by significant advancements in flow cytometry,facilitated by the expansion of bio-particle sorting applications.In particular,various innovative sorting technologies with improved detection accuracy have emerged.This paper reviews the principles and current development of conventional and microfluidic sorting approaches in flow cytometry and further introduces the diverse applications of flow cytometry in fields such as oncology and immunology.Despite notable progress,further research is essential to improve the accuracy of sorting and applicability of flow cytometry.展开更多
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supported by National Natural Science Foundation of China (62103050)National Key Research and Development Program of China (2022YFA1207100 and 2023YFE0112400)+3 种基金Beijing Natural Science Foundation (2242018)BIT Research and Innovation Promoting Project (2023CX01002)Open Research Fund of State Key Laboratory of Digital Medical Engineering (2023-K02)Open Research Fund of State Key Laboratory of Optoelectronic Materials and Technologies (Sun Yat-sen University) (OEMT-2022KF-09)。
文摘Microproteomics, the profiling of protein expressions in small cell populations or individual cells, is essential for understanding complex biological systems. However, sample loss and insufficient sensitivity of analytical techniques pose severe challenges to this field. Microfluidics, particularly droplet-based microfluidics, provides an ideal approach by enabling miniaturized and integrated workflows to process samples and offers several advantages, including reduced sample loss, low reagent consumption, faster reaction times, and improved throughput. Droplet-based microfluidics manipulates droplets of fluids to function as discrete reaction units, enabling complex chemical reactions and biological workflows in a miniaturized setting. This article discusses a variety of on-chip functions of droplet-based microfluidics,including cell sorting, cell culture, and sample processing. We then highlight recent advances in the mass spectrometry(MS)-based analysis of single cells using droplet-based microfluidic platforms, including digital microfluidics(DMF). Finally, we review the integrated DMF–MS systems that enable automated and parallel proteomic profiling of single cells with high sensitivity and discuss the applications of the technology and its future perspectives.
基金Grant sponsor:the Science and Technology Projects of Quanzhou,grant number:2019N085Sgrant sponsor:Startup Fund for Scientific Research,Fujian Medical University,grant number:2018QH1100
文摘Objective:Sperm preparation techniques and cryopreservation are widely used in assisted reproductive techniques(ART).How to improve the quality of sperm management is a matter of great concern.Phospholipase C-zeta(PLCζ)is considered a sperm-specific agent that activates oocyte activation and thus playing a crucial role in male fertility.However,the potential mechanisms by which semen processing and cryopreservation on PLCζcontribute to keyhole have not been addressed.Methods:In this study,semen samples were taken from have not been addressed 10 normozoospermic men.Each semen sample was assigned to the following groups:density gradient centrifugation(DGC)as control,microfluidic sorting,and cryopreservation.Sperm parameters of molity,viability,membrane integrity,and intracellular ROS were evaluated during sperm preparation and cryopreservation.The expression of PLCζin human sperm was determined by immunofluorescence and western blotting.Results:The results showed that molity,viability,and membrane integrity decreased in cryopreservation group.Intracellular ROS were also significantly increased compared to the the control group.There was no significant difference between DGC and microfluidic sorting group.Our investigation revealed that total levels of PLCζwere comparable between DGC and microfluidic sorting,but there were significantly reduced levels of PLCζafter cryopreservation as quantified by both immunofluorescenceand immunoblotting.PLCζimmunofluorescence in sperm revealed different PLCζlocalization patterns around the acrosomal(Ac),equatorial(Eq),post-acrosomal(PA)areas of sperm heads,and their combination.The predominant patterns of PLCζlocalization in DGC were similar to that of microfluidic sorting,with strong,with staining.In contrast,PLCζstaining in freeze-thawed sperm was considerably weaker fluorescence intensity.Conclusion:This study clarified the mechanism of sperm preparation and cryopreservation underlying effect on sperm characteristic,accompanied with PLCζexpresion.We demonstrated that microfluidic sorting provides a highly efficient preparation method for clinical selection of PLCζ-expressing sperm comparable to DGC gene expression.It is suggested that the cryopreservation of sperm has a significant detrimental effect on PLCζ.
文摘Droplet microfluidics,which encapsulates individual cells within separate microreactors,has become an essential tool for single-cell phenotypic and genotypic analysis.However,the efficiency of single-cell encapsulation is limited by the Poisson distribution governing the encapsulation process,resulting in most droplets being either empty or containing multiple cells.Traditional single-cell sorting methods typically rely on fluorescence labeling for identification,but this approach not only increases experimental costs and complexity but can also impact cell viability.Additionally,current label-free sorting methods still encounter difficulties in accurately detecting multicellular droplets and small cellular aggregates.To address these challenges,this paper proposes an intelligent sorting system that combines YOLOv8 object detection and BoTSORT tracking algorithms.This system enables real-time analysis of droplet images,facilitating precise identification,counting,and automated sorting of target droplets.To validate the system’s performance,polystyrene microspheres were used to simulate real cells in sorting tests.The results demonstrated that,under label-free conditions,the system significantly outperformed traditional fluorescence labeling methods in both classification accuracy and sorting efficiency.This system provides an effective,label-free solution for cell sorting,with potential applications in precision medicine,single-cell sequencing,and drug screening.
基金supported by the Guizhou Province High-level Innovative Talent Project(Qiankehe Platform Talent-GCC[2022]027-1)the National Key Research and Development Program of China(2019YFA0904800).
文摘Soft rot is a destructive disease that inflicts significant losses on agricultural production and the economy post-harvest.Biocontrol strategies based on antagonistic microorganisms have a broad application prospect to fight against plant pathogens.This study utilized fluorescence-activated droplet sorting(FADS)technology as an alternative to traditional plate culture methods to isolate microorganisms with antagonistic activity against the soft rot pathogen Erwinia carotovora Ecc15.Initially,the culture performance of the FADS platform was evaluated by analyzing bacterial diversity in droplet culture samples and agar plate culture samples,our data showed that droplet culture exhibited higher species richness and diversity than plate culture,and more than 95%of the operational taxonomic units(OTUs)in the droplet samples belonged to the rare biosphere.Additionally,we developed a green fluorescent protein(GFP)-Ecc15-based FADS screening system,which achieved an enrichment ratio of up to 148.Using this system,we successfully screened 32 antagonistic bacteria from rhizosphere soil sample of healthy konjac plants,and some may be novel microbial resources,including the genera Lelliottia,Buttiauxella and Leclercia.Notably,strain D-62 exhibited the strongest antibacterial ability against Ecc15,with an inhibition zone diameter of(20.86±1.56)mm.In vivo experiments conducted on the corms of Amorphophallus konjac demonstrated that strain D-62 could effectively reduce the infection ability of Ecc15 to the corms,indicating that strain D-62 has the potential to be developed as a biocontrol agent.Our findings suggested that the FADS screening system showed a screening efficiency approximately 3×10^(3)times higher than plate screening system,while significantly reducing costs of infrastructure,labor and consumables,it provides theoretical guidance for the screening of other plant pathogen biocontrol bacteria.
基金supported by the National Natural Science Foun-dation of China(Nos.31800848 and 21775101).
文摘Droplet-based microfluidic technology can be utilized as a microreactor to prepare novel functional monodisperse microcapsules.In this study,a droplet-based microfluidic chip with surface modification,which allowed the one-step preparation of double emulsion microcapsules.An O/W/O double emulsion using polyethylene(glycol)diacrylate(PEGDA)solution as the intermediate water phase was prepared by regulating the hydrophilicity and hydrophobicity of the chip surface,with PEGDA microcapsules prepared using UV polymerization.And then anti-tumor drug paclitaxel and neurotoxin 6-OHDA were encapsulated in microcapsules for drug and toxicology evaluation,respectively.Compared to controls,drug-loaded mi-crocapsules caused a significant increase in the death rate of PC12 cells.This indicates that the obtained drug-loaded microcapsules could be used in drug evaluation and potentially in drug screening and deliv-ery.
文摘The compartimentation of fluids in the microliter, nanoliter and picoliter range leads recently to many applications of microfluidics in material development, diagnostics and biological screenings. Droplet-based microfluidics allows the improvement of nanoparticle homogeneity and the tuning of particle properties. It supports combinatorial synthesis of inorganic as well as organic substances and can be applied for the cultivation and screening of bacteria, eucaryotic cells and fish embryos. The well-ordered handling and the addressing of microfluid segments improves the information transfer between chemical, biological and electronic systems. Despite this remarkable technical progress, there is a particular importance of microfluidics for future nanotechnological solutions. The hierarchical spatial organization of liquids, particles and gels in microfluidics represents a fundamental biomimetic principle which overcomes the limits of planar technology and opens the gate for realizing complex structured threedimensional nanoarchitectures. Recent applications of microstructured fluids in chemistry and biology and concepts for future developments will be discussed.
基金supported by the Key Research and Development Project of Hubei Province,China(No.2021BCA111)。
文摘The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing intensely rely on centrifugation and wash steps that may induce mechanical damage and oxidative stress to sperm.Although a few microfluidic sperm sorting devices may avoid these adverse effects by exploiting intrinsic guidance mechanisms of sperm swimming,none of these approaches have been fully validated by clinical-grade assessment criteria.In this study,a microfluidic sperm sorting device that enables the selection of highly motile and functional sperm via their intrinsic thermotaxis is presented.Bioinspired by the temperature microenvironment in the fallopian tube during natural sperm selection,a microfluidic device with controllable temperature gradients along the sperm separation channel was designed and fabricated.This study investigated the optimal temperature conditions for human sperm selection and fully characterized thermotaxis-selected sperm with 45 human sperm samples.Results indicated that a temperature range of 35–36.5℃along the separation channel significantly improves human sperm motility rate((85.25±6.28)%vs.(60.72±1.37)%;P=0.0484),increases normal sperm morphology rate((16.42±1.43)%vs.(12.55±0.88)%;P<0.0001),and reduces DNA fragmentation((7.44±0.79)%vs.(10.36±0.72)%;P=0.0485)compared to the nonthermotaxis group.Sperm thermotaxis is species-specific,and selected mouse sperm displayed the highest motility in response to a temperature range of 36–37.5℃ along the separation channel.Furthermore,IVF experiments indicated that the selected sperm permitted an increased fertilization rate and improved embryonic development from zygote to blastocyst.This microfluidic thermotaxic selection approach will be translated into clinical practice to improve the IVF success rate for patients with oligozoospermia and asthenozoospermia.
文摘This numerical study proposes a cell sorting technique based on dielectrophoresis(DEP)in a microfluidic chip.Under the joint effect of DEP and fluid drag,white blood cells and circulating tumor cells are separated because of different dielectric properties.First,the mathematical models of device geometry,single cell,DEP force,electric field,and flow field are established to simulate the cell motion.Based on the simulation model,important boundary parameters are discussed to optimize the cell sorting ability of the device.A proper matching relationship between voltage and flow rate is then provided.The inlet and outlet conditions are also investigated to control the particle motion in the flow field.The significance of this study is to verify the cell separating ability of the microfluidic chip,and to provide a logistic design for the separation of rare diseased cells.
基金supported by the Science and Technology Project of the Hebei Education Department[No.BJK2023016]the Central Guidance on Local Science and Technology Development Fund[Grant No.226Z1701G].
文摘Circulating tumor cells(CTCs)are essential biomarkers for liquid biopsies,which are important in the early screening,prognosis,and real-time monitoring of cancer.However,CTCs are less abundant in the peripheral blood of patients,therefore,their isolation is necessary.Recently,the use of microfluidics for CTC sorting has become a research hotspot owing to its low cost,ease of integration,low sample consumption,and unique advantages in the manipulation of micron-sized particles.Herein,we review the latest research on microfluidics-based CTC sorting.Specifically,we consider active sorting using external fields(electric,magnetic,acoustic,and optical tweezers)and passive sorting using the flow effects of cells in specific channel structures(microfiltration sorting,deterministic lateral displacement sorting,and inertial sorting).The advantages and limitations of each method and their recent applications are summarized here.To conclude,a forward-looking perspective is presented on future research on the microfluidic sorting of CTCs.
基金financially supported by the National Natural Science Foundation of China (22025801, 21991101, and 21736006)。
文摘Lead halide perovskite nanocrystals(NCs)exhibit high photoluminescence quantum yield(PLQY),high defect tolerance,narrow half peak width,and wide luminous gamut,making them the ideal optoelectronic materials in numerous fields.Nonetheless,their production still suffers from the limited productivity at the bench level.In this work,we fabricated CsPbX3(X=Cl,Br,I)NCs within droplet-based micro-reactors,where both the nucleation and growth processes could be precisely controlled inside 130-nL microdroplets.This provides a new paradigm for the large-scale synthesis of perovskite NCs with high PLQY.Compared with other synthetic methods,this method can increase the concentration of reactant precursors by 3±116 times,while lowering the ligand to reactant ratio to 2%±50%of the commonly used hot-injection method.By modulating the reaction temperature and residence time,the structure-function relationship between the morphology of NCs and PL properties was extensively investigated.The microfluidic-based process allows the flexible adjustment in the proportion of PbX2 precursors to achieve the fabrication of perovskite NCs whose luminescence range covers the entire visible spectrum(406±677 nm)within one reaction.Finally,perovskite NCs with different halide ions were encapsulated in polymethyl methacrylate to prepare a colored light-emitting diode strip.
基金This work was supported by the National Key Research and Development Program of China(2020YFA0908200)the National Natural Science Foundation of China(T2225003,52073060 and 61927805)+1 种基金Guangdong Basic and Applied Basic Research Foundation(2021B1515120054)the Shenzhen Fundamental Research Pro-gram(JCYJ20190813152616459 and JCYJ20210324133214038).
文摘Sorting high-quality sperm with intact DNA,normal morphology,and active motility is crucial for clinically assisted reproductive technology,which influences the success of treatment and the health of offspring.Currently,microfluidic technology has been developed as a powerful platform for sperm sorting owing to its ability to manipulate fluid at the microscale and handle small samples.Specifically,microfluidic technology provides the necessary stimuli including fluid stimulus,chemical induction,and shape sift,which supports researchers in developing various sperm-sorting devices.According to the sorting principle,these devices can be divided into three categories:active sorting devices based on sperm rheological properties,passive sorting devices based on sperm physical properties,and external stimuli-induced sorting devices.Hence,we review a broad range of researches about sperm sorting with microfluidics and briefly present the properties of sperm and female reproductive tract to assist the design of microfluidic sperm sorting devices.
基金supported by the National Key Research and Development Program of China(No.2022YFC2406300)Natural Science Foundation of Beijing(No.L222140)the Funding of Beijing Laboratory of Biomedical Detection Technology and Instrument.
文摘Flow cytometry is a powerful technique for rapidly analyzing the physical and biological characteristics of small biological particles,such as cells,as well as sorting specific targets.This capability has made it indispensable in a range of biological fields,including cell sequencing,drug development,medical diagnosis,and environmental monitoring.Over the past few decades,these areas have been revolutionized by significant advancements in flow cytometry,facilitated by the expansion of bio-particle sorting applications.In particular,various innovative sorting technologies with improved detection accuracy have emerged.This paper reviews the principles and current development of conventional and microfluidic sorting approaches in flow cytometry and further introduces the diverse applications of flow cytometry in fields such as oncology and immunology.Despite notable progress,further research is essential to improve the accuracy of sorting and applicability of flow cytometry.
