适配体是一类特异的核酸序列,具有靶分子广、特异性强、稳定等优点.该类核酸分子在体外通过SELEX(systematic evolution of ligands by exponential enrichment)技术(系统进化的指数富集技术)鉴定和筛选得到.相对于抗体,适配体为诊断和...适配体是一类特异的核酸序列,具有靶分子广、特异性强、稳定等优点.该类核酸分子在体外通过SELEX(systematic evolution of ligands by exponential enrichment)技术(系统进化的指数富集技术)鉴定和筛选得到.相对于抗体,适配体为诊断和检测分析系统中的识别配基提供了另一个选择.适配体生物传感器是将生物识别元件和信号转换元件紧密结合,从而检测目标化合物的分析装置.适配体生物传感器在微生物检测方面具有分析速度快、灵敏度高、专一性强等特点,在微生物检测中显示出良好的应用前景.介绍了适配体、SELEX流程以及适配体传感器,综述了适配体传感器在微生物检测中的应用.展开更多
Ochratoxin A(OTA),one of the most dangerous mycotoxins for human health,has been subjected to numerous studies for separation and detection in minimal amounts.Aptamers as novel recognition elements have been employed ...Ochratoxin A(OTA),one of the most dangerous mycotoxins for human health,has been subjected to numerous studies for separation and detection in minimal amounts.Aptamers as novel recognition elements have been employed to fabricate ultrasensitive biosensors for the detection of OTA and designing delicate analytical tools.This review attempted to comprehensively examine all reported aptamer-based detection and separation platforms for ochratoxin.The most relevant databases were considered to discover all specific aptamers for dealing with OTA.Aptamer-based detection and separation devices specified for OTA were searched for,analyzed,discussed,and classified based on their specifications.The optical aptasensors have gathered a higher interest than electrochemical aptasensors,which can achieve a lower limit of detections.Moreover,some extraction platforms based on these aptamers were also found.However,aptamer-based devices seem to have some challenges in their application.展开更多
It is important to develop methods to determine microbial toxins at trace levels since these toxins are ubiquitous commonly found in water and foods,and pose potential threats to both human health and ecosystem safety...It is important to develop methods to determine microbial toxins at trace levels since these toxins are ubiquitous commonly found in water and foods,and pose potential threats to both human health and ecosystem safety.Taking the advantages of ultrahigh electron-transfer capability,extra-large surface area and easily functionalized ability,the graphene-based nanocomposites have been employed to fabricate electrochemical biosensors including immunosensors and aptasensors for detecting microbial toxins with high sensitivity.The specificity and selectivity of the electrochemical biosensors for targeting toxins can be achieved by combining graphene nanocomposites with antibodies and/or aptamers.The graphene nanocompositebased electrochemical biosensors could become a promising technique in the detection of microbial toxins for public and environmental health protection.展开更多
In this paper, the DNA-templated Ag/Pt bimetallic nanoclusters were successfully synthesized using an optimized synthetic scheme. The obtained DNA-Ag/Pt NCs have an ultrasmall particle size and excellent distribution....In this paper, the DNA-templated Ag/Pt bimetallic nanoclusters were successfully synthesized using an optimized synthetic scheme. The obtained DNA-Ag/Pt NCs have an ultrasmall particle size and excellent distribution. The DNA-Ag/Pt NCs show intrinsic peroxidase-mimicking activity and can effectively catalyze the H2O2-mediated oxidation of a substrate, 3,30,5,50-tetramethylbenzidine（TMB）, to produce a blue colored product. Based on this specific property, we employed the aptamer of VEGF to design a label-free electrochemical biosensor for VEGF detection. Under the optimized experimental conditions, a linear range from 6.0 pmol/L to 20 pmol/L was obtained with a detection limit of 4.6 pmol/L. The proposed biosensor demonstrated its high specificity for VEGF and could directly detect the VEGF concentration in human serum samples of breast cancer patients with satisfactory results. This novel electrochemical aptasensor was simple and convenient to use and was cost-effective and label-free in design, and would hold potential applications in medical diagnosis and treatment.展开更多
A label-free fluorescent aptasensor for specific and ultrasensitive monitoring ochratoxin A（OTA） was developed using the specific aptamer of OTA（OSA） as recognition dement, an aggregation-induced emission（AIE） m...A label-free fluorescent aptasensor for specific and ultrasensitive monitoring ochratoxin A（OTA） was developed using the specific aptamer of OTA（OSA） as recognition dement, an aggregation-induced emission（AIE） molecule（a 9,10-distyrylanthracene with two ammonium groups, DSAI） as a fluorescent probe, and graphene oxide（GO） as a quencher. In the absence of OTA, the AIE probe DSAI and OSA complex（DSAI/OSA） is adsorbed on the GO surface, and the fluorescence of DSAI will be quenched efficiently via the fluorescence resonance energy transfer（FRET） from DSAI to GO. Upon the OTA addition, a more stable complex（OSA-OTA） is formed and released from GO. Meanwhile, DSAI and OSA-OTA can form a new complex（DSAI/OSA-OTA）, then the fluorescent signal of DSAI recovers gradually. Therefore, by introducing GO and DSAI, the fluorescence signal of DSAI can be easily turned from ＂off＂ to ＂on＂ after the addition of OTA, and the ultrasensitive detection of OTA by monitoring the change of the fluorescence signal of DSAI can be readily realized. The detection limit of the assay can reach 0.324 nmol/L with a linear detection range of 10-200 nmol/L. And the aptasensor exhibits high selectivity for OTA against other analogues. Moreover, it has been successfully applied for the detection of OTA in red wine samples.展开更多
Access to security and safe food is a basic human necessity and essential for a sustainable world. To perform hi-end rood safety analysis and risk assessment with state of the art technologies is of utmost importance ...Access to security and safe food is a basic human necessity and essential for a sustainable world. To perform hi-end rood safety analysis and risk assessment with state of the art technologies is of utmost importance thereof. With applications as exemplified by microfiuidic immunoassay, aptasensor, direct analysis in real time, high resolution mass spectrometry, benchmark dose and chemical specific adjustment factor, this review presents frontier food safety analysis and risk assessment technologies, from which both food quality and public health will benefit undoubtedly in a foreseeable future.展开更多
文摘适配体是一类特异的核酸序列,具有靶分子广、特异性强、稳定等优点.该类核酸分子在体外通过SELEX(systematic evolution of ligands by exponential enrichment)技术(系统进化的指数富集技术)鉴定和筛选得到.相对于抗体,适配体为诊断和检测分析系统中的识别配基提供了另一个选择.适配体生物传感器是将生物识别元件和信号转换元件紧密结合,从而检测目标化合物的分析装置.适配体生物传感器在微生物检测方面具有分析速度快、灵敏度高、专一性强等特点,在微生物检测中显示出良好的应用前景.介绍了适配体、SELEX流程以及适配体传感器,综述了适配体传感器在微生物检测中的应用.
文摘Ochratoxin A(OTA),one of the most dangerous mycotoxins for human health,has been subjected to numerous studies for separation and detection in minimal amounts.Aptamers as novel recognition elements have been employed to fabricate ultrasensitive biosensors for the detection of OTA and designing delicate analytical tools.This review attempted to comprehensively examine all reported aptamer-based detection and separation platforms for ochratoxin.The most relevant databases were considered to discover all specific aptamers for dealing with OTA.Aptamer-based detection and separation devices specified for OTA were searched for,analyzed,discussed,and classified based on their specifications.The optical aptasensors have gathered a higher interest than electrochemical aptasensors,which can achieve a lower limit of detections.Moreover,some extraction platforms based on these aptamers were also found.However,aptamer-based devices seem to have some challenges in their application.
文摘It is important to develop methods to determine microbial toxins at trace levels since these toxins are ubiquitous commonly found in water and foods,and pose potential threats to both human health and ecosystem safety.Taking the advantages of ultrahigh electron-transfer capability,extra-large surface area and easily functionalized ability,the graphene-based nanocomposites have been employed to fabricate electrochemical biosensors including immunosensors and aptasensors for detecting microbial toxins with high sensitivity.The specificity and selectivity of the electrochemical biosensors for targeting toxins can be achieved by combining graphene nanocomposites with antibodies and/or aptamers.The graphene nanocompositebased electrochemical biosensors could become a promising technique in the detection of microbial toxins for public and environmental health protection.
基金support of the National Natural Science Foundation of China (Nos. 21375017, 21105012 and 21205015)the National Science Foundation for Distinguished Young Scholars of Fujian Province (No. 2013J06003)+3 种基金the Key Project of Fujian Science and Technology (No. 2013Y0045)the Program for New Century Excellent Talents of Colleges and Universities in Fujian Province (Nos. JA13130 and JA13088)the Program for Fujian University Outstanding Youth Scientific Research (Nos. JA11105 and JA10295)the Foundation of Fuzhou Science and Technology Bureau (No. 2013-S-122-4)
文摘In this paper, the DNA-templated Ag/Pt bimetallic nanoclusters were successfully synthesized using an optimized synthetic scheme. The obtained DNA-Ag/Pt NCs have an ultrasmall particle size and excellent distribution. The DNA-Ag/Pt NCs show intrinsic peroxidase-mimicking activity and can effectively catalyze the H2O2-mediated oxidation of a substrate, 3,30,5,50-tetramethylbenzidine（TMB）, to produce a blue colored product. Based on this specific property, we employed the aptamer of VEGF to design a label-free electrochemical biosensor for VEGF detection. Under the optimized experimental conditions, a linear range from 6.0 pmol/L to 20 pmol/L was obtained with a detection limit of 4.6 pmol/L. The proposed biosensor demonstrated its high specificity for VEGF and could directly detect the VEGF concentration in human serum samples of breast cancer patients with satisfactory results. This novel electrochemical aptasensor was simple and convenient to use and was cost-effective and label-free in design, and would hold potential applications in medical diagnosis and treatment.
文摘A label-free fluorescent aptasensor for specific and ultrasensitive monitoring ochratoxin A（OTA） was developed using the specific aptamer of OTA（OSA） as recognition dement, an aggregation-induced emission（AIE） molecule（a 9,10-distyrylanthracene with two ammonium groups, DSAI） as a fluorescent probe, and graphene oxide（GO） as a quencher. In the absence of OTA, the AIE probe DSAI and OSA complex（DSAI/OSA） is adsorbed on the GO surface, and the fluorescence of DSAI will be quenched efficiently via the fluorescence resonance energy transfer（FRET） from DSAI to GO. Upon the OTA addition, a more stable complex（OSA-OTA） is formed and released from GO. Meanwhile, DSAI and OSA-OTA can form a new complex（DSAI/OSA-OTA）, then the fluorescent signal of DSAI recovers gradually. Therefore, by introducing GO and DSAI, the fluorescence signal of DSAI can be easily turned from ＂off＂ to ＂on＂ after the addition of OTA, and the ultrasensitive detection of OTA by monitoring the change of the fluorescence signal of DSAI can be readily realized. The detection limit of the assay can reach 0.324 nmol/L with a linear detection range of 10-200 nmol/L. And the aptasensor exhibits high selectivity for OTA against other analogues. Moreover, it has been successfully applied for the detection of OTA in red wine samples.
基金financially supported by the Beijing Municipal Science and Technology Project, China (Z131110000613066)the Educational and Teaching Reform Project for Graduate Students, China (G-JG-XJ201408)the Beijing Key Laboratory of Bioprocess, China
文摘Access to security and safe food is a basic human necessity and essential for a sustainable world. To perform hi-end rood safety analysis and risk assessment with state of the art technologies is of utmost importance thereof. With applications as exemplified by microfiuidic immunoassay, aptasensor, direct analysis in real time, high resolution mass spectrometry, benchmark dose and chemical specific adjustment factor, this review presents frontier food safety analysis and risk assessment technologies, from which both food quality and public health will benefit undoubtedly in a foreseeable future.
