Fluorescence polarization is related to the dipole orientation of chromophores,making fuores-cence polarization microscopy possible to_reveal structures and functions of tagged cellularorganelles and biological macrom...Fluorescence polarization is related to the dipole orientation of chromophores,making fuores-cence polarization microscopy possible to_reveal structures and functions of tagged cellularorganelles and biological macromolecules.Several recent super resolution techniques have beenapplied to fluorescence polarization microscopy,achieving dipole measurement at nanoscale.In this review,we summarize both difraction limited and super resolution fluorescence polari-zation microscopy techniques,as well as their applications in biological imaging.展开更多
As a promising signaling transduction approach, fluorescence polarization(FP)/fluorescence anisotropy(FA), provides a powerful quantitative tool for the rotational motion of fluorescently labeled molecules in chemical...As a promising signaling transduction approach, fluorescence polarization(FP)/fluorescence anisotropy(FA), provides a powerful quantitative tool for the rotational motion of fluorescently labeled molecules in chemical or biological homogeneous systems. Unlike fluorescence intensity, FP/FA is almost independent the concentration or quantum of fluorophores, but they are highly dependent on the size or molecular weight of the molecules or materials attached to fluorophores. Recently, significant progress in FP/FA was made, due to the introduction of some nanomaterials as FP/FA enhancers. The detection sensitivity is thus greatly improved by using nanomaterials as FP/FA enhancers, and nanomaterial-based FP/FA is currently used successfully in immunoassay, and analysis of protein, nucleic acid, small molecule and metal ion.Nanomaterial-based FP/FA provides a new kind of strategy to design fluorescent sensors and establishes innovative analytical methods. In this review, we summarize the scientific publications in the field of FP/FA sensor in recent five years, and first introduce the recent progress of FP/FA sensor based on nanomaterial. Subsequently, the various analytical applications of FP/FA based on nanomaterial are discussed. Finally, we provide perspectives on the current challenges and future prospects in this promising field.展开更多
Bisphenol A(BPA)is one of the environmental endocrine disruptors(EDCs),and BPA contamination in environment can cause high risks to human health.Rapid determination of BPA on sites is in high demand in environmental a...Bisphenol A(BPA)is one of the environmental endocrine disruptors(EDCs),and BPA contamination in environment can cause high risks to human health.Rapid determination of BPA on sites is in high demand in environmental analysis.Taking advantage of aptamers as affinity ligands and fluorescence anisotropy(FA)analysis,we developed a simple and rapid FA assay for BPA by employing a single tetramethylrhodamine(TMR)labeled short 35-mer DNA aptamer against BPA.The assay is based on the BPA-binding induced conformation change of TMR-labeled aptamer and alteration of interaction between TMR and guanine bases,resulting in change of FA signals.We screened the FA change of aptamer probes having TMR label on a specific site of the aptamer upon BPA addition.The aptamer with a TMR label on the 22nd T base showed large FA-decreasing response to BPA and maintained good binding affinity to BPA.By using this TMR-labeled aptamer,we achieved FA detection of BPA with a detection limit of 0.5μmol/L under the optimized conditions.This assay was selective towards BPA and enabled the detection of BPA spiked in tap water sample,showing the potential applications on water samples.展开更多
Fluorescence anisotropy(FA)assay in homogenous solution is simple,sensitive and reproducible.Here,we reported an aptamer structure switch FA assay for detection of aflatoxin B1(AFB1),one of the most toxic mycotoxins,b...Fluorescence anisotropy(FA)assay in homogenous solution is simple,sensitive and reproducible.Here,we reported an aptamer structure switch FA assay for detection of aflatoxin B1(AFB1),one of the most toxic mycotoxins,by using tetra methylrhodamine(TMR)-labeled aptamer probe and its complementary DNA(cDNA)with tandem G bases extension,to meet the demand in sensitive and selective detection of AFB1,The hybridization of aptamer and cDNA drew TMR close to the repeated guanine(G)bases,and a high FA value was induced due to TMR-G inte raction and re stricted local rotation of TMR.In the presence of AFB1,aptamer bound to AFB1 instead of the cDNA due to competition.Thus,the TMR-G interaction was eliminated,and FA value of TMR decreased.This assay enabled the detection of AFB1 with detection limit of 125 pmol/L and dynamic range from 125 pmol/L to 31.2 nmol/L.展开更多
Fluorescence anisotropy was employed for the investigation of the association between AlS 4Pc and BSA. The average binding number of AlS 4Pc to BSA was calculated and the constants of association reaction occurring in...Fluorescence anisotropy was employed for the investigation of the association between AlS 4Pc and BSA. The average binding number of AlS 4Pc to BSA was calculated and the constants of association reaction occurring in the medium of pH 7 0 were shown. The results revealed that the interaction between AlS 4Pc and BSA was strong, which implied that AlS 4Pc may be stored and transferred by serum albumin. The merits of the method used were also pointed out.展开更多
Many papers have used fluorescent probe diffusion to infer membrane viscosity but the measurement is actually an assay of the free volume of the membrane. The free volume is also related to the membrane tension. Thus,...Many papers have used fluorescent probe diffusion to infer membrane viscosity but the measurement is actually an assay of the free volume of the membrane. The free volume is also related to the membrane tension. Thus, changes in probe mobility refer equally well to changes in membrane tension. In complicated structures like cell membranes, it appears more intuitive to consider variations in free volume as referring to the effect of domains structures and interactions with the cytoskeleton than changes in viscosity since tension is a state variable and viscosity is not.展开更多
基金supported by the National Instrument Development Special Program(2013YQ03065102)the Natural Science Foundation of China(614-75010,61428501)Science and Technology Commission of Shanghai Municipality(16DZ-1100300).
文摘Fluorescence polarization is related to the dipole orientation of chromophores,making fuores-cence polarization microscopy possible to_reveal structures and functions of tagged cellularorganelles and biological macromolecules.Several recent super resolution techniques have beenapplied to fluorescence polarization microscopy,achieving dipole measurement at nanoscale.In this review,we summarize both difraction limited and super resolution fluorescence polari-zation microscopy techniques,as well as their applications in biological imaging.
基金the financial support provided by the National Natural Science Foundation of China (Nos. 21822407, 21405163)the top priority program of “OneThree-Five” Strategic Planning of Lanzhou Institute of Chemical Physics, CAS
文摘As a promising signaling transduction approach, fluorescence polarization(FP)/fluorescence anisotropy(FA), provides a powerful quantitative tool for the rotational motion of fluorescently labeled molecules in chemical or biological homogeneous systems. Unlike fluorescence intensity, FP/FA is almost independent the concentration or quantum of fluorophores, but they are highly dependent on the size or molecular weight of the molecules or materials attached to fluorophores. Recently, significant progress in FP/FA was made, due to the introduction of some nanomaterials as FP/FA enhancers. The detection sensitivity is thus greatly improved by using nanomaterials as FP/FA enhancers, and nanomaterial-based FP/FA is currently used successfully in immunoassay, and analysis of protein, nucleic acid, small molecule and metal ion.Nanomaterial-based FP/FA provides a new kind of strategy to design fluorescent sensors and establishes innovative analytical methods. In this review, we summarize the scientific publications in the field of FP/FA sensor in recent five years, and first introduce the recent progress of FP/FA sensor based on nanomaterial. Subsequently, the various analytical applications of FP/FA based on nanomaterial are discussed. Finally, we provide perspectives on the current challenges and future prospects in this promising field.
基金supported by the National Natural Science Foundation of China(Nos.21874146,21575153,21435008)。
文摘Bisphenol A(BPA)is one of the environmental endocrine disruptors(EDCs),and BPA contamination in environment can cause high risks to human health.Rapid determination of BPA on sites is in high demand in environmental analysis.Taking advantage of aptamers as affinity ligands and fluorescence anisotropy(FA)analysis,we developed a simple and rapid FA assay for BPA by employing a single tetramethylrhodamine(TMR)labeled short 35-mer DNA aptamer against BPA.The assay is based on the BPA-binding induced conformation change of TMR-labeled aptamer and alteration of interaction between TMR and guanine bases,resulting in change of FA signals.We screened the FA change of aptamer probes having TMR label on a specific site of the aptamer upon BPA addition.The aptamer with a TMR label on the 22nd T base showed large FA-decreasing response to BPA and maintained good binding affinity to BPA.By using this TMR-labeled aptamer,we achieved FA detection of BPA with a detection limit of 0.5μmol/L under the optimized conditions.This assay was selective towards BPA and enabled the detection of BPA spiked in tap water sample,showing the potential applications on water samples.
基金the National Natural Science Foundation of China(Nos.21874146,21575153,21435008)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB14030200)。
文摘Fluorescence anisotropy(FA)assay in homogenous solution is simple,sensitive and reproducible.Here,we reported an aptamer structure switch FA assay for detection of aflatoxin B1(AFB1),one of the most toxic mycotoxins,by using tetra methylrhodamine(TMR)-labeled aptamer probe and its complementary DNA(cDNA)with tandem G bases extension,to meet the demand in sensitive and selective detection of AFB1,The hybridization of aptamer and cDNA drew TMR close to the repeated guanine(G)bases,and a high FA value was induced due to TMR-G inte raction and re stricted local rotation of TMR.In the presence of AFB1,aptamer bound to AFB1 instead of the cDNA due to competition.Thus,the TMR-G interaction was eliminated,and FA value of TMR decreased.This assay enabled the detection of AFB1 with detection limit of 125 pmol/L and dynamic range from 125 pmol/L to 31.2 nmol/L.
文摘Fluorescence anisotropy was employed for the investigation of the association between AlS 4Pc and BSA. The average binding number of AlS 4Pc to BSA was calculated and the constants of association reaction occurring in the medium of pH 7 0 were shown. The results revealed that the interaction between AlS 4Pc and BSA was strong, which implied that AlS 4Pc may be stored and transferred by serum albumin. The merits of the method used were also pointed out.
文摘Many papers have used fluorescent probe diffusion to infer membrane viscosity but the measurement is actually an assay of the free volume of the membrane. The free volume is also related to the membrane tension. Thus, changes in probe mobility refer equally well to changes in membrane tension. In complicated structures like cell membranes, it appears more intuitive to consider variations in free volume as referring to the effect of domains structures and interactions with the cytoskeleton than changes in viscosity since tension is a state variable and viscosity is not.
