mRNA quantification is very important in molecular biological researches. Traditional spectrophotometric method cannot distinguish DNA, rRNA and tRNA species from mRNA. Northern blot can be used for mRNA quantificatio...mRNA quantification is very important in molecular biological researches. Traditional spectrophotometric method cannot distinguish DNA, rRNA and tRNA species from mRNA. Northern blot can be used for mRNA quantification but is known to be time consuming. To rapidly detect mRNA levels, we developed an optical thin-film biosensor chip based method, to quantify mRNA in samples. After total RNA was extracted, the mRNA with poly（A） tails was reverse transcribed with oligo（dT）20 primers and dNTPs mixed with digoxigenin（DIG）-11-dUTE The transcribed first strand cDNA was hybridized with oligo（dA）20 nucleotide probes spotted on optical thin-film biosensor chips. Excess first strand cDNA, single-strand RNA, and mis-matched DNA/DNA hybrids were removed by washing. The perfect-matched DNA/DNA hybrid was detected with anti-DIG-AP （alkaline phosphatase） conjugate and then incubated with NBT/BCIP substrate for color development. The range of the color is from purplish red to blue, according to the cDNA mass deposited on chip sur- face. Detection of mRNA levels from Arabidopsis samples proved that this method is feasible for mRNA quantification, and has great potential for application in mRNA quantification in various organisms.展开更多
Here we report the adaptation and optimization of an effi cient, accurate and inexpensive assay that employs custom-designed silicon-based optical thin-fi lm biosensor chips to detect unique transgenes in genetically ...Here we report the adaptation and optimization of an effi cient, accurate and inexpensive assay that employs custom-designed silicon-based optical thin-fi lm biosensor chips to detect unique transgenes in genetically modi-展开更多
A simple and rapid optical biosensor for the determination of ammonium was developed by immobilization of gluta-mate dehydrogenase (GLDH) and diaphorase (Dph) in chitosan film coated on a glass slide employing thiazol...A simple and rapid optical biosensor for the determination of ammonium was developed by immobilization of gluta-mate dehydrogenase (GLDH) and diaphorase (Dph) in chitosan film coated on a glass slide employing thiazolyl blue tetrazolium bromide (MTT) as a color indicator. The developed biosensor displays a purple color formation of formazan attributed to the unreacted NADH in the reaction system in the presence of ammonium. The color intensity was found to decrease proportionally with the increase of ammonium concentrations after 10 min exposure. The linearity of the biosensor towards ammonium was in the range of 16.8 – 70 μM (R2 = 0.9955) with detection limit of 11 μM. A good agreement (R2 = 0.9984) with indothymol method was obtained in the measurement of fish pond water samples. The effect of potential interferences such as metals ion has also been evaluated.展开更多
In this paper,we propose a theoretical model of the surface plasmon resonance-based optical fiber biosensor for detecting glucose concentration.The Au/ZnO/WS2 multilayer film is coated around optical fiber.Compared wi...In this paper,we propose a theoretical model of the surface plasmon resonance-based optical fiber biosensor for detecting glucose concentration.The Au/ZnO/WS2 multilayer film is coated around optical fiber.Compared with the conventional surface plasmon resonance sensor,WS2 material can increase the sensitivity of the biosensor.The absorption capacity of WS2 is used to load glucose oxidase by forming a sensitive area to recognize glucose.Refractive index of the solution is calculated and then the concentration of the glucose can be obtained by the correspondence between refractive index and glucose concentration.The highest sensitivity of the SPR biosensor with a structure of 40-nm Au/5-nm ZnO/14 layers of WS2 is 4310 nm/RIU.The proposed WS2-based SPR fiber biosensor has a unique effect on the detection of glucose concentration.It is expected to have potential applications in future medical blood glucose concentration detection.展开更多
An optical fiber bienzyme sensor based on the luminol chemiluminescent reaction was developed and demonstrated to be sensitive to glucose. Glucose oxidase(GOD) and horseradish peroxidase(HRP) were co-immobilized by mi...An optical fiber bienzyme sensor based on the luminol chemiluminescent reaction was developed and demonstrated to be sensitive to glucose. Glucose oxidase(GOD) and horseradish peroxidase(HRP) were co-immobilized by microencapsulation in a sol-gel film derived from tetraethyl orthosilicate(TEOS). The calibration plots for glucose were established by the optical fiber glucose sensor fabricated by attaching the bienzyme silica gel onto the glass window of the fiber bundle. The linear range was 0 2-2 mmol/L and the detection limit was approximately 0 12 mmol/L. The relative standard deviation was 5.3% ( n =6). The proposed biosensor was applied to glucose assay in ofloxacin injection successfully.展开更多
An optical biosensor with a stirred cuvette has been used to monitor the interaction of immobilized wheat germ agglutinin （WGA） with two water-soluble cationic porphyrins, The association constants （Ka） of the fre...An optical biosensor with a stirred cuvette has been used to monitor the interaction of immobilized wheat germ agglutinin （WGA） with two water-soluble cationic porphyrins, The association constants （Ka） of the free base porphyrin and its Zn（Ⅱ） complex form were 2. 66 and 27.31 × 10^5 l,/mol at 20 ℃ respectively. The interactions of the free base porphyrin were further investigated at temperatures between 15 ℃ and 37 ℃, The thermodynamics parameters, changes in free energy, enthalpy and entropy, were -31.23, 22.92, 54.15 ld/mol respectively. The heat capacity change was -355.53 J · mol^-1·K^-1 The binding was driven by entropic contribution, and showed strong enthalpy-entropy compensation. It was governed primarily by hydrophobic forces.展开更多
Objective: To establish a DNA detection platform based on a tapered optical fiber to detect Leptospira DNA by targeting the leptospiral secY gene.Methods: The biosensor works on the principle of light propagating in t...Objective: To establish a DNA detection platform based on a tapered optical fiber to detect Leptospira DNA by targeting the leptospiral secY gene.Methods: The biosensor works on the principle of light propagating in the special geometry of the optical fiber tapered from a waist diameter of 125 to 12 μm. The fiber surface was functionalized through a cascade of chemical treatments and the immobilization of a DNA capture probe targeting the secY gene. The presence of the target DNA was determined from the wavelength shift in the optical transmission spectrum.Results: The biosensor demonstrated good sensitivity, detecting Leptospira DNA at 0.001 ng/μL, and was selective for Leptospira DNA without cross-reactivity with non-leptospiral microorganisms. The biosensor specifically detected DNA that was specifically amplified through the loop-mediated isothermal amplification approach.Conclusions: These findings warrant the potential of this platform to be developed as a novel alternative approach to diagnose leptospirosis.展开更多
The efficient immobilization of capture antibodies is crucial for timely pathogen detection during global pandemic outbreaks.Therefore,we proposed a silica-binding protein featuring core functional domains(cSP).It com...The efficient immobilization of capture antibodies is crucial for timely pathogen detection during global pandemic outbreaks.Therefore,we proposed a silica-binding protein featuring core functional domains(cSP).It comprises a peptide with a silica-binding tag designed to adhere to silica surfaces and tandem protein G fragments(2C2)for effective antibody capture.This innovation facilitates precise site-directed immobilization of antibodies onto silica surfaces.We applied cSP to silica-coated optical fibers,creating a fiber-optic biolayer interferometer(FO-BLI)biosensor capable of monitoring the monkeypox virus(MPXV)protein A29L in spiked clinical samples to rapidly detect the MPXV.The cSP-based FO-BLI biosensor for MPXV demonstrated a limit of detection(LOD)of 0.62 ng/mL in buffer,comparable to the 0.52 ng/mL LOD achieved using a conventional streptavidin(SA)-based FO-BLI biosensor.Furthermore,it achieved LODs of 0.77 ng/mL in spiked serum and 0.80 ng/mL in spiked saliva,exhibiting no cross-reactivity with other viral antigens.The MPXV detection process was completed within 14 min.We further proposed a cSP-based multi-virus biosensor strategy capable of detecting various pandemic strains,such as MPXV,the latest coronavirus disease(COVID)variants,and influenza A protein,to extend its versatility.The proposed cSP-modified FO-BLI biosensor has a high potential for rapidly and accurately detecting MPXV antigens,making valuable contributions to epidemiological studies.展开更多
Luciferase from firefly lantern extract was immobilized on CNBr activated Sepharose 4B. The kinetic properties of immobilized luciferase were extensively studied. The K m′ for D luciferin is 11.9 μmol/L, the ...Luciferase from firefly lantern extract was immobilized on CNBr activated Sepharose 4B. The kinetic properties of immobilized luciferase were extensively studied. The K m′ for D luciferin is 11.9 μmol/L, the optimum pH and temperature for Sepharose bound enzyme were 7.8 and 25℃ respectively. A luminescence fiber optic biosensor, making use of immobilized crude luciferase, was developed for assay of ATP. The peak light intensity was linear with respect to ATP concentration in range of 10 -9 -10 -5 mol/L. A biological application was also demonstrated with the determination of serum ATP from rats bred in low versus normal oxygen environments.展开更多
Fiber-optic DNA biosensors are a kind of ana-lytic setups, which convert the Waston-Crick base pairs matching duplex or Hoogsteen’s tri-plex (T/A-T, C/G-C) formation into a readable analytical signals when functional...Fiber-optic DNA biosensors are a kind of ana-lytic setups, which convert the Waston-Crick base pairs matching duplex or Hoogsteen’s tri-plex (T/A-T, C/G-C) formation into a readable analytical signals when functionalized single- strands DNA (ssDNA) or double-strands DNA (dsDNA) of interest are immobilized on the sur-face of fiber-optic hybrids with target DNA or interacts with ligands. This review will provide the information about the fiber-optic DNA bio-sensors classified into two categories depend-ing on the end fiber and side fiber with or with-out the labels—label-free fiber-optic DNA bio-sensors and labeled fiber-optic DNA biosensor in recent years. Both are dissertated, and em-phasis is on the label-free fiber-optic DNA bio-sensors. Fiber-optic DNA biosensors had got great progresses because fiber-optic has more advantages over the other transducers and are easily processed by nanotechnology. So fiber- optic DNA biosensors have increasingly at-tracted more attention to research and develop the new fiber-optic DNA biosensors that inte-grated with the “nano-bio-info” technology for in vivo test, single molecular detection and on-line medical diagnosis. Finally, future pros-pects to the fiber-optic DNA biosensors are predicted.展开更多
Detecting multiple analytes simultaneously,crucial in disease diagnosis and treatment prognosis,remains challenging.While planar sensing platforms demonstrate this capability,optical fiber sensors still lag behind.An ...Detecting multiple analytes simultaneously,crucial in disease diagnosis and treatment prognosis,remains challenging.While planar sensing platforms demonstrate this capability,optical fiber sensors still lag behind.An operando dual lossy mode resonance(LMR)biosensor fabricated on a D-shaped single-mode fiber(SMF)is proposed for quantification of clinical indicators of inflammatory process,like in COVID-19 infection.Dual LMRs,created via two-step deposition process,yield a nanostructure with distinct SnO_(2) thicknesses on the flat surface of the fiber.Theoretical and experimental analyses confirm its feasibility,showing a sensitivity around 4500 nm/RIU for both LMRs.A novel insight in spatially-separated biofunctionalization of the sensitive fiber regions is validated through fluorescence assays,showcasing selectivity for different immunoglobulins.Real-time and label-free detection of two inflammatory markers,C-reactive protein and Ddimer,empowers the platform capability with a minimum detectable concentration below 1μg/mL for both biomolecules,which is of clinical interest.This proof-of-concept work provides an important leap in fiber-based biosensing for effective and reliable multi-analyte detection,presenting a novel,compact and multi-functional analytical tool.展开更多
Optical fiber sensors have gained significant attention in recent years owing to their remarkable advantages of remote operation and rapid response.The integration of optical fiber sensing with the microfluidics techn...Optical fiber sensors have gained significant attention in recent years owing to their remarkable advantages of remote operation and rapid response.The integration of optical fiber sensing with the microfluidics technology has paved the way for the establishment of optical fiber optofluidic sensing.Optical fiber optofluidic systems possess the advantages of the low invasiveness,compact structure,excellent biocompatibility,and the ability to handle small analyte volumes,rendering them particularly suitable for serving as chemical sensors and biosensors.In this paper,we present an in-depth overview of optical fiber optofluidic chemical sensors and biosensors.Firstly,we provide a comprehensive summary of the types of optical fibers commonly employed in optofluidic chemical and biosensing,elucidating their distinct attributes and performance characteristics.Subsequently,we introduce and thoroughly analyze several representative sensing mechanisms employed in optical fiber optofluidic systems and main performance parameters.Furthermore,this review delves into the modification and functionalization of optical fibers.Additionally,we showcase typical biosensing and chemical sensing applications to demonstrate the practicality and versatility of optical fiber optofluidic sensing.Finally,the conclusion and outlook are given.展开更多
In producing high-performance optical biosensors,the selected coupling agent and its fixation mode play an essential role as one of the decisive conditions for antibody incubation.In this work,we designed optical fibe...In producing high-performance optical biosensors,the selected coupling agent and its fixation mode play an essential role as one of the decisive conditions for antibody incubation.In this work,we designed optical fiber biosensors by electrochemical polymerization to enable low detection limit(LOD)immunoassay.Based on the optical fiber lossy mode resonance(OF-LMR)achieved by In_(2)O_(3)-SnO_(2)-90/10 wt%(ITO),we have simultaneously implemented the electropolymerized dopamine(ePDA)film on the ITO-coated fiber via the electrochemical method,utilizing the excellent electrical conductivity of ITO.After that,the immunoglobulin G(IgG)antibody layer was immobilized on the entire sensing region with the assistance of the ePDA film.The results of immunoassay were analyzed by recording the shift of the LMR resonance wavelength to verify the sensor performance.The LOD was evaluated as the lowest concentration of human IgG detected by the OF-LMR sensor,which was confirmed to be 4.20 ng·mL^(-1).Furthermore,the sensor achieved selective detection for specific antigens and exhibited a good recovery capability in chicken serum samples.The developed scheme provides a feasible opportunity to enhance the intersection of electrochemistry and optics subjects and also offers a new promising solution to achieve the immunoassay.展开更多
The precise and rapid detection of micro-ribonucleic acid(microRNA)in the incipient stages of cancer can effectively elucidatethe pathogenesis,migration,and development of tumors.Most of the current microRNA detection...The precise and rapid detection of micro-ribonucleic acid(microRNA)in the incipient stages of cancer can effectively elucidatethe pathogenesis,migration,and development of tumors.Most of the current microRNA detection methods require largequantities of purified samples,labeling,extended incubation times,and cell lysis,leading to complex procedures that demandlabor-intensive preparations and stringent experimental conditions.In this work,we develop a portable and multifunctionalbiosensor based on an optical microfiber for the detection of microRNA in the early stages of cancer.An innovative grapheneoxide-supported bimetallic nanorod(GO-Au NR-Ag NR)interface is engineered on the surface of the optical microfiber toenhance sensor sensitivity for the early detection of ultralow concentrations of microRNA and to integrate cell lysis capabilities.With the enhancement of interface,the sensor is able to detect microRNA-21 at concentrations ranging from 10zmol/L to 0.1 nmol/L,with a limit of detection(LOD)of 0.25 amol/L.It is also capable of detecting microRNA-21 in bodyfluids,such as sweat and serum,with LODs of 0.5 amol/L and 0.9 amol/L,respectively.The nano-interface enables the useof photothermal effects by the microfiber to lyse cells and directly detect intracellular microRNA-21,significantly reducingsample extraction time and simplifying the extraction and detection process.This work provides a portable,ultrasensitive,compact,efficient,and non-invasive tool for point-of-care testing.展开更多
The ultralow limit of detection(LoD)and exceptional sensitivity of biosensors are a significant challenge currently faced in the field.To address this challenge,this work proposes a highly sensitive laser ring cavity ...The ultralow limit of detection(LoD)and exceptional sensitivity of biosensors are a significant challenge currently faced in the field.To address this challenge,this work proposes a highly sensitive laser ring cavity biosensor capable of detecting low concentrations of des-γ-carboxy prothrombin(DCP).A tapered W-shaped fiber probe based on multi-mode fiber(MMF)-multi-core fiber(MCF)-MMF is developed to excite strong evanescent waves(EWs).By immobilizing gold nanorods(GNRs)on the fiber probe,localized surface plasmon resonance(LSPR)is generated at the near infrared wavelength to further enhance the sensitivity of the fiber probe.Moreover,an erbium-doped fiber(EDF)ring laser with a narrow full width at half maximum(FWHM)of 0.11 nm is employed as a light source.The spectrum with narrow FWHM has been demonstrated to obtain lower Lo D.Compared to the ASE light source,the Lo D of the laser ring cavity can be reduced by an order of magnitude.The developed biosensor is capable of detecting DCP within a concentration range of 0-1000 ng/mL,and the detection sensitivity of 0.265 nm/lg(ng/mL)and the Lo D of 367.6 pg/m L are obtained.In addition,the proposed laser ring cavity biosensor demonstrates good specificity,reproducibility,and repeatability by corresponding tests.The study results indicate that the proposed biosensor has potential in the detection of hepatocellular carcinoma markers.展开更多
Ultrasensitive nanomechanical instruments,e.g.atomic force microscopy(AFM),can be used to perform delicate biomechanical measurements and reveal the complex mechanical environment of biological processes.However,these...Ultrasensitive nanomechanical instruments,e.g.atomic force microscopy(AFM),can be used to perform delicate biomechanical measurements and reveal the complex mechanical environment of biological processes.However,these instruments are limited because of their size and complex feedback system.In this study,we demonstrate a miniature fiber optical nanomechanical probe(FONP)that can be used to detect the mechanical properties of single cells and in vivo tissue measurements.A FONP that can operate in air and in liquids was developed by programming a microcantilever probe on the end face of a single-mode fiber using femtosecond laser two-photon polymerization nanolithography.To realize stiffness matching of the FONP and sample,a strategy of customizing the microcantilever’s spring constant according to the sample was proposed based on structure-correlated mechanics.As a proof-of concept,three FONPs with spring constants varying from 0.421 N m^(−1)to 52.6 N m^(−1)by more than two orders of magnitude were prepared.The highest microforce sensitivity was 54.5 nmμN^(−1)and the detection limit was 2.1 nN.The Young’s modulus of heterogeneous soft materials,such as polydimethylsiloxane,muscle tissue of living mice,onion cells,and MCF-7 cells,were successfully measured,which validating the broad applicability of this method.Our strategy provides a universal protocol for directly programming fiber-optic AFMs.Moreover,this method has no special requirements for the size and shape of living biological samples,which is infeasible when using commercial AFMs.FONP has made substantial progress in realizing basic biological discoveries,which may create new biomedical applications that cannot be realized by current AFMs.展开更多
Waterborne viruses that can be harmful to human health pose significant challenges globally,affecting health care systems and the economy.Identifying these waterborne pathogens is essential for preventing diseases and...Waterborne viruses that can be harmful to human health pose significant challenges globally,affecting health care systems and the economy.Identifying these waterborne pathogens is essential for preventing diseases and protecting public health.However,handling complex samples such as human and wastewater can be challenging due to their dynamic and complex composition and the ultralow concentration of target analytes.This review presents a comprehensive overview of the latest breakthroughs in waterborne virus biosensors.It begins by highlighting several promising strategies that enhance the sensing performance of optical and electrochemical biosensors in human samples.These strategies include optimizing bioreceptor selection,transduction elements,signal amplification,and integrated sensing systems.Furthermore,the insights gained from biosensing waterborne viruses in human samples are applied to improve biosensing in wastewater,with a particular focus on sampling and sample pretreatment due to the dispersion characteristics of waterborne viruses in wastewater.This review suggests that implementing a comprehensive system that integrates the entire waterborne virus detection process with high-accuracy analysis could enhance virus monitoring.These findings provide valuable insights for improving the effectiveness of waterborne virus detection,which could have significant implications for public health and environmental management.展开更多
Optical fiber biosensors(OFBs)have emerged as a versatile and highly sensitive technology,with various implementations such as fiber Bragg gratings,interferometric techniques,and D-shaped fibers,particularly those tha...Optical fiber biosensors(OFBs)have emerged as a versatile and highly sensitive technology,with various implementations such as fiber Bragg gratings,interferometric techniques,and D-shaped fibers,particularly those that leverage surface plasmon resonance effects.Classifying these sensors based on target analytes underscores their adaptability and broad range of applications.Despite significant progress,challenges such as repeatability,multiplexing,and data interpretation remain key barriers to widespread practical adoption.To address these limitations,recent innovations focus on artificial intelligence algorithms for enhanced data processing,as well as novel materials that improve sensitivity and the repeatability of functionalization.The integration of label-free detection,enabled by surface functionalization,further enhances biosensing capabilities.Moreover,the unique combination of small fiber dimensions,low samplevolume detection,and multiplexing capabilities positions OFBs as a promising alternative to existing commercial solutions.As demand for precise,real-time,and multi-analyte sensing grows,OFBs are poised to become a cornerstone technology,particularly in the context of Healthcare 5.0,where personalized and intelligent diagnostics are essential to advancing medical applications.We summarize advances in OFBs over the past decade,highlighting their functionalities and applications across multiple fields,including medical diagnostics,environmental monitoring,and industrial process control.Finally,we explore future directions for this field.Reported detection limits below 1 femtomolar(10-15mol∕L),selectivity ratios exceeding 100:1,and operational stability over 60 days illustrate ongoing progress in overcoming challenges related to sensitivity,specificity,and long-term performance.The integration of the Internet of Things will enable seamless communication with external devices.Innovations in material science can further improve sensitivity and repeatability,allowing probing in low-sample environments and supporting new designs with label-free and multiplexing capabilities.Continued progress in these areas will pave the way for large-scale production and commercialization of OFBs.展开更多
In this work,we report innovative fiber optic biosensors exploiting localized surface plasmon resonance(LSPR)generated by gold nanostructures,specifically spherical nanoparticles(NPs)and nanostars(NSs),immobilized on ...In this work,we report innovative fiber optic biosensors exploiting localized surface plasmon resonance(LSPR)generated by gold nanostructures,specifically spherical nanoparticles(NPs)and nanostars(NSs),immobilized on uncladded silica multi-mode fibers to form a compact reflective probe architecture.The transition from NPs to NSs produced a redshift of the LSPR peak from 545 nm to 665 nm and markedly enhanced bulk refractive index sensitivity:16 nm diameter NPs reached 156 nm/RIU,while 78 nm diameter NSs achieved 402 nm/RIU.To demonstrate biosensing capability,the nanostructure coated fibers were biofunctionalized with anti-cortisol antibodies,enabling selective detection of cortisol,a key biomarker for stress and endocrine disorders.The resulting sensors exhibited a wide dynamic range(1 pg/mL100μg/mL),with the NS-based configuration achieving an outstanding limit of detection of 0.1 pg/mL.This broad range encompasses clinically relevant cortisol levels,underscoring the potential of LSPR-based fiber probes for non-invasive stress monitoring and personalized healthcare,where the synergy between nanostructure design and fiber integration paves the way for compact,label-free,highly sensitive point-of-care diagnostics.展开更多
文摘mRNA quantification is very important in molecular biological researches. Traditional spectrophotometric method cannot distinguish DNA, rRNA and tRNA species from mRNA. Northern blot can be used for mRNA quantification but is known to be time consuming. To rapidly detect mRNA levels, we developed an optical thin-film biosensor chip based method, to quantify mRNA in samples. After total RNA was extracted, the mRNA with poly（A） tails was reverse transcribed with oligo（dT）20 primers and dNTPs mixed with digoxigenin（DIG）-11-dUTE The transcribed first strand cDNA was hybridized with oligo（dA）20 nucleotide probes spotted on optical thin-film biosensor chips. Excess first strand cDNA, single-strand RNA, and mis-matched DNA/DNA hybrids were removed by washing. The perfect-matched DNA/DNA hybrid was detected with anti-DIG-AP （alkaline phosphatase） conjugate and then incubated with NBT/BCIP substrate for color development. The range of the color is from purplish red to blue, according to the cDNA mass deposited on chip sur- face. Detection of mRNA levels from Arabidopsis samples proved that this method is feasible for mRNA quantification, and has great potential for application in mRNA quantification in various organisms.
文摘Here we report the adaptation and optimization of an effi cient, accurate and inexpensive assay that employs custom-designed silicon-based optical thin-fi lm biosensor chips to detect unique transgenes in genetically modi-
文摘A simple and rapid optical biosensor for the determination of ammonium was developed by immobilization of gluta-mate dehydrogenase (GLDH) and diaphorase (Dph) in chitosan film coated on a glass slide employing thiazolyl blue tetrazolium bromide (MTT) as a color indicator. The developed biosensor displays a purple color formation of formazan attributed to the unreacted NADH in the reaction system in the presence of ammonium. The color intensity was found to decrease proportionally with the increase of ammonium concentrations after 10 min exposure. The linearity of the biosensor towards ammonium was in the range of 16.8 – 70 μM (R2 = 0.9955) with detection limit of 11 μM. A good agreement (R2 = 0.9984) with indothymol method was obtained in the measurement of fish pond water samples. The effect of potential interferences such as metals ion has also been evaluated.
基金Project supported by the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20171442)the China Postdoctoral Science Foundation(Grant No.2018T110480)+2 种基金the Open Foundation of State Key Laboratory of Millimeter Waves,China(Grant No.K202003)the Open Foundation of State Key Laboratory of Luminescent Materials and Devices,China(Grant No.2020-skllmd-03)the Fund from the Research Center of Optical Communications Engineering&Technology,Jiangsu Province,China(Grant No.ZXF201904).
文摘In this paper,we propose a theoretical model of the surface plasmon resonance-based optical fiber biosensor for detecting glucose concentration.The Au/ZnO/WS2 multilayer film is coated around optical fiber.Compared with the conventional surface plasmon resonance sensor,WS2 material can increase the sensitivity of the biosensor.The absorption capacity of WS2 is used to load glucose oxidase by forming a sensitive area to recognize glucose.Refractive index of the solution is calculated and then the concentration of the glucose can be obtained by the correspondence between refractive index and glucose concentration.The highest sensitivity of the SPR biosensor with a structure of 40-nm Au/5-nm ZnO/14 layers of WS2 is 4310 nm/RIU.The proposed WS2-based SPR fiber biosensor has a unique effect on the detection of glucose concentration.It is expected to have potential applications in future medical blood glucose concentration detection.
文摘An optical fiber bienzyme sensor based on the luminol chemiluminescent reaction was developed and demonstrated to be sensitive to glucose. Glucose oxidase(GOD) and horseradish peroxidase(HRP) were co-immobilized by microencapsulation in a sol-gel film derived from tetraethyl orthosilicate(TEOS). The calibration plots for glucose were established by the optical fiber glucose sensor fabricated by attaching the bienzyme silica gel onto the glass window of the fiber bundle. The linear range was 0 2-2 mmol/L and the detection limit was approximately 0 12 mmol/L. The relative standard deviation was 5.3% ( n =6). The proposed biosensor was applied to glucose assay in ofloxacin injection successfully.
文摘An optical biosensor with a stirred cuvette has been used to monitor the interaction of immobilized wheat germ agglutinin （WGA） with two water-soluble cationic porphyrins, The association constants （Ka） of the free base porphyrin and its Zn（Ⅱ） complex form were 2. 66 and 27.31 × 10^5 l,/mol at 20 ℃ respectively. The interactions of the free base porphyrin were further investigated at temperatures between 15 ℃ and 37 ℃, The thermodynamics parameters, changes in free energy, enthalpy and entropy, were -31.23, 22.92, 54.15 ld/mol respectively. The heat capacity change was -355.53 J · mol^-1·K^-1 The binding was driven by entropic contribution, and showed strong enthalpy-entropy compensation. It was governed primarily by hydrophobic forces.
基金funded by Universiti Putra Malaysia through the Geran Inisiatif Putra Siswazah (GP-IPS/2019/9678200)。
文摘Objective: To establish a DNA detection platform based on a tapered optical fiber to detect Leptospira DNA by targeting the leptospiral secY gene.Methods: The biosensor works on the principle of light propagating in the special geometry of the optical fiber tapered from a waist diameter of 125 to 12 μm. The fiber surface was functionalized through a cascade of chemical treatments and the immobilization of a DNA capture probe targeting the secY gene. The presence of the target DNA was determined from the wavelength shift in the optical transmission spectrum.Results: The biosensor demonstrated good sensitivity, detecting Leptospira DNA at 0.001 ng/μL, and was selective for Leptospira DNA without cross-reactivity with non-leptospiral microorganisms. The biosensor specifically detected DNA that was specifically amplified through the loop-mediated isothermal amplification approach.Conclusions: These findings warrant the potential of this platform to be developed as a novel alternative approach to diagnose leptospirosis.
基金This research was supported by Westlake University,China(Startup funds)the Research Center for Industries of the Future of Westlake University,China(Grant No.:WU2022C040)the National Natural Science Foundation of China(Grant No.:82104122).
文摘The efficient immobilization of capture antibodies is crucial for timely pathogen detection during global pandemic outbreaks.Therefore,we proposed a silica-binding protein featuring core functional domains(cSP).It comprises a peptide with a silica-binding tag designed to adhere to silica surfaces and tandem protein G fragments(2C2)for effective antibody capture.This innovation facilitates precise site-directed immobilization of antibodies onto silica surfaces.We applied cSP to silica-coated optical fibers,creating a fiber-optic biolayer interferometer(FO-BLI)biosensor capable of monitoring the monkeypox virus(MPXV)protein A29L in spiked clinical samples to rapidly detect the MPXV.The cSP-based FO-BLI biosensor for MPXV demonstrated a limit of detection(LOD)of 0.62 ng/mL in buffer,comparable to the 0.52 ng/mL LOD achieved using a conventional streptavidin(SA)-based FO-BLI biosensor.Furthermore,it achieved LODs of 0.77 ng/mL in spiked serum and 0.80 ng/mL in spiked saliva,exhibiting no cross-reactivity with other viral antigens.The MPXV detection process was completed within 14 min.We further proposed a cSP-based multi-virus biosensor strategy capable of detecting various pandemic strains,such as MPXV,the latest coronavirus disease(COVID)variants,and influenza A protein,to extend its versatility.The proposed cSP-modified FO-BLI biosensor has a high potential for rapidly and accurately detecting MPXV antigens,making valuable contributions to epidemiological studies.
文摘Luciferase from firefly lantern extract was immobilized on CNBr activated Sepharose 4B. The kinetic properties of immobilized luciferase were extensively studied. The K m′ for D luciferin is 11.9 μmol/L, the optimum pH and temperature for Sepharose bound enzyme were 7.8 and 25℃ respectively. A luminescence fiber optic biosensor, making use of immobilized crude luciferase, was developed for assay of ATP. The peak light intensity was linear with respect to ATP concentration in range of 10 -9 -10 -5 mol/L. A biological application was also demonstrated with the determination of serum ATP from rats bred in low versus normal oxygen environments.
文摘Fiber-optic DNA biosensors are a kind of ana-lytic setups, which convert the Waston-Crick base pairs matching duplex or Hoogsteen’s tri-plex (T/A-T, C/G-C) formation into a readable analytical signals when functionalized single- strands DNA (ssDNA) or double-strands DNA (dsDNA) of interest are immobilized on the sur-face of fiber-optic hybrids with target DNA or interacts with ligands. This review will provide the information about the fiber-optic DNA bio-sensors classified into two categories depend-ing on the end fiber and side fiber with or with-out the labels—label-free fiber-optic DNA bio-sensors and labeled fiber-optic DNA biosensor in recent years. Both are dissertated, and em-phasis is on the label-free fiber-optic DNA bio-sensors. Fiber-optic DNA biosensors had got great progresses because fiber-optic has more advantages over the other transducers and are easily processed by nanotechnology. So fiber- optic DNA biosensors have increasingly at-tracted more attention to research and develop the new fiber-optic DNA biosensors that inte-grated with the “nano-bio-info” technology for in vivo test, single molecular detection and on-line medical diagnosis. Finally, future pros-pects to the fiber-optic DNA biosensors are predicted.
基金financial support from the Spanish Agencia Estatal de Investigación (AEI) through project PID2023-149895OB-I00a predoctoral research grant from the Public University of Navarrafinancial support under the National Recovery and Resilience Plan (NRRP),Mission 4,Component 2,Investment 1.1,Call for tender No.1409 published on 14.9.2022 by the Italian Ministry of University and Research (MUR),funded by the European Union–NextGenerationEU–Project Title‘‘Fiber optics sensors as a platform for cancer diagnosis and in vitro model testing”–CUP B53D23024170001-Grant Assignment Decree No.1383 adopted on 01/09/2023 by the Italian MUR.
文摘Detecting multiple analytes simultaneously,crucial in disease diagnosis and treatment prognosis,remains challenging.While planar sensing platforms demonstrate this capability,optical fiber sensors still lag behind.An operando dual lossy mode resonance(LMR)biosensor fabricated on a D-shaped single-mode fiber(SMF)is proposed for quantification of clinical indicators of inflammatory process,like in COVID-19 infection.Dual LMRs,created via two-step deposition process,yield a nanostructure with distinct SnO_(2) thicknesses on the flat surface of the fiber.Theoretical and experimental analyses confirm its feasibility,showing a sensitivity around 4500 nm/RIU for both LMRs.A novel insight in spatially-separated biofunctionalization of the sensitive fiber regions is validated through fluorescence assays,showcasing selectivity for different immunoglobulins.Real-time and label-free detection of two inflammatory markers,C-reactive protein and Ddimer,empowers the platform capability with a minimum detectable concentration below 1μg/mL for both biomolecules,which is of clinical interest.This proof-of-concept work provides an important leap in fiber-based biosensing for effective and reliable multi-analyte detection,presenting a novel,compact and multi-functional analytical tool.
基金supported by the Heilongjiang Provincial Natural Science Foundation of China(Grant No.LH2021F019)Fundamental Research Funds for the Central Universities,China(Grant No.3072022CF2506)National Natural Science Foundation of China(Grant Nos.62305082,11574061,and 62065001).
文摘Optical fiber sensors have gained significant attention in recent years owing to their remarkable advantages of remote operation and rapid response.The integration of optical fiber sensing with the microfluidics technology has paved the way for the establishment of optical fiber optofluidic sensing.Optical fiber optofluidic systems possess the advantages of the low invasiveness,compact structure,excellent biocompatibility,and the ability to handle small analyte volumes,rendering them particularly suitable for serving as chemical sensors and biosensors.In this paper,we present an in-depth overview of optical fiber optofluidic chemical sensors and biosensors.Firstly,we provide a comprehensive summary of the types of optical fibers commonly employed in optofluidic chemical and biosensing,elucidating their distinct attributes and performance characteristics.Subsequently,we introduce and thoroughly analyze several representative sensing mechanisms employed in optical fiber optofluidic systems and main performance parameters.Furthermore,this review delves into the modification and functionalization of optical fibers.Additionally,we showcase typical biosensing and chemical sensing applications to demonstrate the practicality and versatility of optical fiber optofluidic sensing.Finally,the conclusion and outlook are given.
基金supported in parts by National Key Scientific Instrument and Equipment Development Projects of China(Grant No.2022YFF0706000)National Natural Science Foundation of China(Grant No.62035006)+1 种基金Independent Innovation Found of Tianjin University,China(Grant No.2023XCG-0028)Tianjin Research Innovation Project for Postgraduate Students,China(Grant No.2022BKY064).
文摘In producing high-performance optical biosensors,the selected coupling agent and its fixation mode play an essential role as one of the decisive conditions for antibody incubation.In this work,we designed optical fiber biosensors by electrochemical polymerization to enable low detection limit(LOD)immunoassay.Based on the optical fiber lossy mode resonance(OF-LMR)achieved by In_(2)O_(3)-SnO_(2)-90/10 wt%(ITO),we have simultaneously implemented the electropolymerized dopamine(ePDA)film on the ITO-coated fiber via the electrochemical method,utilizing the excellent electrical conductivity of ITO.After that,the immunoglobulin G(IgG)antibody layer was immobilized on the entire sensing region with the assistance of the ePDA film.The results of immunoassay were analyzed by recording the shift of the LMR resonance wavelength to verify the sensor performance.The LOD was evaluated as the lowest concentration of human IgG detected by the OF-LMR sensor,which was confirmed to be 4.20 ng·mL^(-1).Furthermore,the sensor achieved selective detection for specific antigens and exhibited a good recovery capability in chicken serum samples.The developed scheme provides a feasible opportunity to enhance the intersection of electrochemistry and optics subjects and also offers a new promising solution to achieve the immunoassay.
基金the National Natural Science Foundation of China(No.62375108)the Guangzhou Science and Technology Plan Project(No.2023A03J0130)+3 种基金the Guangdong Basic and Applied Basic Research Foundation(No.2024A1515010088)the Local Innovative and Research Teams Project of the Guangdong Pearl River Talents Program(No.2019BT02X105)the Postdoctoral Fellowship Program(Grade B)of China Postdoctoral Science Foundation(No.GZB20230265)the National Innovation and Entrepreneurship Training Program For Undergraduate(No.S202410559087).
文摘The precise and rapid detection of micro-ribonucleic acid(microRNA)in the incipient stages of cancer can effectively elucidatethe pathogenesis,migration,and development of tumors.Most of the current microRNA detection methods require largequantities of purified samples,labeling,extended incubation times,and cell lysis,leading to complex procedures that demandlabor-intensive preparations and stringent experimental conditions.In this work,we develop a portable and multifunctionalbiosensor based on an optical microfiber for the detection of microRNA in the early stages of cancer.An innovative grapheneoxide-supported bimetallic nanorod(GO-Au NR-Ag NR)interface is engineered on the surface of the optical microfiber toenhance sensor sensitivity for the early detection of ultralow concentrations of microRNA and to integrate cell lysis capabilities.With the enhancement of interface,the sensor is able to detect microRNA-21 at concentrations ranging from 10zmol/L to 0.1 nmol/L,with a limit of detection(LOD)of 0.25 amol/L.It is also capable of detecting microRNA-21 in bodyfluids,such as sweat and serum,with LODs of 0.5 amol/L and 0.9 amol/L,respectively.The nano-interface enables the useof photothermal effects by the microfiber to lyse cells and directly detect intracellular microRNA-21,significantly reducingsample extraction time and simplifying the extraction and detection process.This work provides a portable,ultrasensitive,compact,efficient,and non-invasive tool for point-of-care testing.
基金Natural Science Foundation of Shandong Province(ZR2022QF137)Double-Hundred Talent Plan of Shandong Province+3 种基金Special Construction Project Fund for Shandong Province Taishan Mountain ScholarsLiaocheng University(318052205,318052341)Science and Technology Support Plan for Youth Innovation of Colleges and Universities of Shandong Province of China(2022KJ107)Koneru Lakshmaiah Education Foundation。
文摘The ultralow limit of detection(LoD)and exceptional sensitivity of biosensors are a significant challenge currently faced in the field.To address this challenge,this work proposes a highly sensitive laser ring cavity biosensor capable of detecting low concentrations of des-γ-carboxy prothrombin(DCP).A tapered W-shaped fiber probe based on multi-mode fiber(MMF)-multi-core fiber(MCF)-MMF is developed to excite strong evanescent waves(EWs).By immobilizing gold nanorods(GNRs)on the fiber probe,localized surface plasmon resonance(LSPR)is generated at the near infrared wavelength to further enhance the sensitivity of the fiber probe.Moreover,an erbium-doped fiber(EDF)ring laser with a narrow full width at half maximum(FWHM)of 0.11 nm is employed as a light source.The spectrum with narrow FWHM has been demonstrated to obtain lower Lo D.Compared to the ASE light source,the Lo D of the laser ring cavity can be reduced by an order of magnitude.The developed biosensor is capable of detecting DCP within a concentration range of 0-1000 ng/mL,and the detection sensitivity of 0.265 nm/lg(ng/mL)and the Lo D of 367.6 pg/m L are obtained.In addition,the proposed laser ring cavity biosensor demonstrates good specificity,reproducibility,and repeatability by corresponding tests.The study results indicate that the proposed biosensor has potential in the detection of hepatocellular carcinoma markers.
基金supported by the National Natural Science Foundation of China(NSFC)(62122057,62075136,62175165)Natural Science Foundation of Guangdong Province(2022B1515120061,2019B1515120042)Science and Technology Innovation Commission of Shenzhen(RCYX20200714114524139,JCYJ20200109114001806).
文摘Ultrasensitive nanomechanical instruments,e.g.atomic force microscopy(AFM),can be used to perform delicate biomechanical measurements and reveal the complex mechanical environment of biological processes.However,these instruments are limited because of their size and complex feedback system.In this study,we demonstrate a miniature fiber optical nanomechanical probe(FONP)that can be used to detect the mechanical properties of single cells and in vivo tissue measurements.A FONP that can operate in air and in liquids was developed by programming a microcantilever probe on the end face of a single-mode fiber using femtosecond laser two-photon polymerization nanolithography.To realize stiffness matching of the FONP and sample,a strategy of customizing the microcantilever’s spring constant according to the sample was proposed based on structure-correlated mechanics.As a proof-of concept,three FONPs with spring constants varying from 0.421 N m^(−1)to 52.6 N m^(−1)by more than two orders of magnitude were prepared.The highest microforce sensitivity was 54.5 nmμN^(−1)and the detection limit was 2.1 nN.The Young’s modulus of heterogeneous soft materials,such as polydimethylsiloxane,muscle tissue of living mice,onion cells,and MCF-7 cells,were successfully measured,which validating the broad applicability of this method.Our strategy provides a universal protocol for directly programming fiber-optic AFMs.Moreover,this method has no special requirements for the size and shape of living biological samples,which is infeasible when using commercial AFMs.FONP has made substantial progress in realizing basic biological discoveries,which may create new biomedical applications that cannot be realized by current AFMs.
基金supported by the Research Center for Industries of the Future of Westlake University,China(Grant No.:210230006022219/001)the National Natural Science Foundation of China(Grant No.:82104122)+1 种基金Westlake University,China(Grant No.:10318A992001)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang,China(Grant No.:2020R01005).
文摘Waterborne viruses that can be harmful to human health pose significant challenges globally,affecting health care systems and the economy.Identifying these waterborne pathogens is essential for preventing diseases and protecting public health.However,handling complex samples such as human and wastewater can be challenging due to their dynamic and complex composition and the ultralow concentration of target analytes.This review presents a comprehensive overview of the latest breakthroughs in waterborne virus biosensors.It begins by highlighting several promising strategies that enhance the sensing performance of optical and electrochemical biosensors in human samples.These strategies include optimizing bioreceptor selection,transduction elements,signal amplification,and integrated sensing systems.Furthermore,the insights gained from biosensing waterborne viruses in human samples are applied to improve biosensing in wastewater,with a particular focus on sampling and sample pretreatment due to the dispersion characteristics of waterborne viruses in wastewater.This review suggests that implementing a comprehensive system that integrates the entire waterborne virus detection process with high-accuracy analysis could enhance virus monitoring.These findings provide valuable insights for improving the effectiveness of waterborne virus detection,which could have significant implications for public health and environmental management.
基金developed within the scope of the project CICECO Aveiro Institute of MaterialsUID/50011/2025(DOI:10.54499/UID/50011/2025)&LA/P/0006/2020(DOI:10.54499/LA/P/0006/2020)+4 种基金financed by national funds through the FCT/MCTES(PIDDAC)co-funded by the European Union under REFRESH—Research Excellence for REgion Sustainability and High-Tech Industries(Project No CZ.10.03.01/00/22-003/0000048)through the Operational Programme Just Transitionprovided by the Ministry of Education,Youth,and Sports of the Czech Republic,and conducted at the VSB-Technical University of Ostrava under Grant Nos.SP2025/039 and SP2025/021funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan(Grant No.AP19576207)by a Nazarbayev University grant(code:20122022FD4134,Project M2O-DISK)。
文摘Optical fiber biosensors(OFBs)have emerged as a versatile and highly sensitive technology,with various implementations such as fiber Bragg gratings,interferometric techniques,and D-shaped fibers,particularly those that leverage surface plasmon resonance effects.Classifying these sensors based on target analytes underscores their adaptability and broad range of applications.Despite significant progress,challenges such as repeatability,multiplexing,and data interpretation remain key barriers to widespread practical adoption.To address these limitations,recent innovations focus on artificial intelligence algorithms for enhanced data processing,as well as novel materials that improve sensitivity and the repeatability of functionalization.The integration of label-free detection,enabled by surface functionalization,further enhances biosensing capabilities.Moreover,the unique combination of small fiber dimensions,low samplevolume detection,and multiplexing capabilities positions OFBs as a promising alternative to existing commercial solutions.As demand for precise,real-time,and multi-analyte sensing grows,OFBs are poised to become a cornerstone technology,particularly in the context of Healthcare 5.0,where personalized and intelligent diagnostics are essential to advancing medical applications.We summarize advances in OFBs over the past decade,highlighting their functionalities and applications across multiple fields,including medical diagnostics,environmental monitoring,and industrial process control.Finally,we explore future directions for this field.Reported detection limits below 1 femtomolar(10-15mol∕L),selectivity ratios exceeding 100:1,and operational stability over 60 days illustrate ongoing progress in overcoming challenges related to sensitivity,specificity,and long-term performance.The integration of the Internet of Things will enable seamless communication with external devices.Innovations in material science can further improve sensitivity and repeatability,allowing probing in low-sample environments and supporting new designs with label-free and multiplexing capabilities.Continued progress in these areas will pave the way for large-scale production and commercialization of OFBs.
基金European Commission(REFRESH CZ.10.03.01/00/22_003/0000048,NextGenEU PRIN 2022 CUP I53D23000390006)Funda????o para a Ciência e a Tecnologia(DigiAqua(PTDC/EEI EEE/0415/2021),CICECO UID/50011/2025)+2 种基金Ministry of Education,Youth,and Sports of the Czech Republic(VSB Technical University of Ostrava SP2026/028,SP2026/012)BRAZIL/CNPq/MCTI/FNDCT(22/2022)BRAZIL/FAPES(20/2022)。
文摘In this work,we report innovative fiber optic biosensors exploiting localized surface plasmon resonance(LSPR)generated by gold nanostructures,specifically spherical nanoparticles(NPs)and nanostars(NSs),immobilized on uncladded silica multi-mode fibers to form a compact reflective probe architecture.The transition from NPs to NSs produced a redshift of the LSPR peak from 545 nm to 665 nm and markedly enhanced bulk refractive index sensitivity:16 nm diameter NPs reached 156 nm/RIU,while 78 nm diameter NSs achieved 402 nm/RIU.To demonstrate biosensing capability,the nanostructure coated fibers were biofunctionalized with anti-cortisol antibodies,enabling selective detection of cortisol,a key biomarker for stress and endocrine disorders.The resulting sensors exhibited a wide dynamic range(1 pg/mL100μg/mL),with the NS-based configuration achieving an outstanding limit of detection of 0.1 pg/mL.This broad range encompasses clinically relevant cortisol levels,underscoring the potential of LSPR-based fiber probes for non-invasive stress monitoring and personalized healthcare,where the synergy between nanostructure design and fiber integration paves the way for compact,label-free,highly sensitive point-of-care diagnostics.
