超痕量分析中的激光诱导荧光检测

本文对激光诱导荧光检测器(LIF-D)及其主要器件激光器、滤光片、透镜、光电检测器、荧光探针及扫描装置的现状和发展趋势作了综述,介绍了LIF在单分子检测中的应用.     

痕量间苯二酚的动力学荧光分析

在硫酸介质中,痕量间苯二酚对甲醛催化氯酸钾氧化罗丹明B使其荧光猝灭具有抑制作用,据此建立了动力学荧光法测定痕量间苯二酚的新方法.方法的线性范围为0.016～0.240mg@L-1,检出限为0.009mg@L-1.此法用于自来水样中间苯二酚含量的测定,并进行了加标回收试验,回收率在98%～103%之间.     

荧光光谱法测定工业废水中痕量汞的研究

利用汞（Ⅱ）在适量一乙醇和β－环糊精存在下对四（４－三甲铵苯基）卟啉（ＴＡＰＰ）的荧光熄灭作用,提出了测量汞的高灵敏荧光光度新方法,拟定条件下的荧光激发峰λｅｘ＝４１４ｎｍ,荧光发射峰λｅｍ＝６４６ｎｍ,荧光熄灭值△Ｆ与Ｈｇ（Ⅱ）的质量浓度在０～３μｇ／２５ｍＬ范围内呈线性关系。本法操作简便,不必加热,也无需催化剂,应用迅速且体系稳定。本法用于测定工业废水等样品中的痕量汞,与其它方法的结果吻合。     

荧光动力学法测定痕量钯

基于在硫酸介质中痕量钯离子对过氧化氢氧化罗丹明6G的催化作用,建立了动力学荧光法测定痕量钯的方法,方法的检出限为0．0183ug.ml^-1,线性范围为0．04－0．48ug.ml^-1,将方法用于合成样品中钯的测定,结果满意。     

苯基荧光酮荧光分光光度法测定痕量锗的研究

锗具有增血、抗炎症、抗衰老等多种医疗功能 ,因此 ,越来越受到人们的关注。荧光光度法测定微量锗已有报道[1～ 4] 。用苯基荧光酮荧光度法测定锗未见报道。本文利用苯基荧光酮与锗在醋酸 醋酸钠缓冲溶液中络合物形成速度快的优势 ,使其先在缓冲溶液中显色 ,然后在 0 .3ｍｏｌ ＬＨＣｌ介质中测定其荧光强度 ,用于粉煤灰中痕量锗的测定 ,得到满意结果。1　实验部分1 1　仪器与试剂ＲＦ - 5 4 0荧光分光光度计 (日本岛津 )。锗标准溶液 ( 1ｇ Ｌ) :称取 0 .1 0 0 0ｇ纯锗粉于 5 0ｍｌ小烧杯中 ,加入 5ｍｌＮａＯＨ ,再加入几滴 30 %Ｈ2 Ｏ2…     

二极管阵列检测-激光诱导荧光光度法测定食品中痕量铜

为了建立食品中痕量铜的新分析方法,本文利用自行组装的激光诱导荧光－CCD二极管阵列检测器－计算机联用装置,研究了铜催化H2O2氧化罗丹明B的反应体系,在氨－氟化铵（pH=9.0)缓冲溶液中,激发波长532．0nm,发射波长580．0nm条件下,采用催化荧光光度法实现了食品样品中痕量铜的测定,方法的线性范围0．5－4．0ug/L,方法的检出限为0.5ug/L,加标回收率为86．9％－108．6％,s相对偏差不大于9．70％。     

荧光猝灭测定痕量钯

报道了Pd(Ⅱ）与碘离子进行氧化还原反应生成游离碘使异硫氰酸荧光素荧光猝灭，借此异硫氰酸荧光素为荧光指示剂间接测定钯的新方法。在pH6.00的条件下，异硫氰酸荧光素的最大激发波长为485nm；最大发射波长为515nm。钯含量在20－200ng/L范围内与体系的荧光强度有良好的线性关系；检出限为6.4ng/L。本法具有灵敏度高、费用低、操作简便、快速等优点，用于样品分析，结果令人满意。     

新型高灵敏电荷耦合器件阵列荧光检测装置

本报道用一般光源溴钨灯及电荷耦合器件阵列检测器组装的荧光检测装置，对装置的各种操作参数进行了优化及评价，此装置测定荧光素的检出限达到５×１０＾－１０ｍｏｌ／Ｌ，线性范围为１×１０＾－９－２×１０＾－６ｍｏｌ／Ｌ。     

催化荧光光度法测定痕量亚硝酸根

1　引　　言亚硝酸根广泛存在于环境、水体、食品等物质中 ,它可与胺类及酰胺类化合物反应生成致癌物亚硝胺 ,因此 ,它是水质、环境、食品等检测的重要项目之一。催化动力学光度法测定亚硝酸根已有不少报道 ,而催化荧光法测定亚硝酸根的报道不多。吡红Ｂ是一种生物染色剂 ,在水溶液中发射红色荧光。作者发现 ,稀磷酸介质中 ,溴酸钾氧化吡红Ｂ使荧光猝灭 ,亚硝酸根对此氧化还原褪色反应具有灵敏催化作用 ,据此建立了测定亚硝酸根的催化荧光光度新方法。该法灵敏度较高 ,选择性好 ,简便快速 ,用于水及蔬菜中痕量亚硝酸根的测定 ,结果满意…     

Fluorescence Signal Amplification Strategies Based on DNA Nanotechnology for miRNA Detection

In this review,the most recent progresses in the field of fluorescence signal amplification strategies based on DNA nanotechnology for miRNA are summarized.The types of signal amplification are given and the principles of amplification strategies are explained,including rolling circle amplification(RCA),catalytic hairpin assembly(CHA),hybridization chain reaction(HCR)and DNA walker.Subsequently,the application of these signal amplification methods in biosensing and bioimaging are covered and described.Finally,the challenges and the outlook of fluorescence signal amplification methods for miRNA detection are briefly commented.     

Determination of Ultratrace Metal Elements in Natural Samples by Laser-induced Fluorescence with Time-gate Technique

The determination of ultratrace metal elements is of great important in geochemistry, chemical exploration and many other fields. The laser-induced fluorescence (LIF) with time-gate technique is an extremely efficient method for the determination of ultratrace concentrations of elements. This paper reports on the high sensitive detection researches in our laboratory, included lead in Antarctic ice-snow samples, gold in geogas, gold and palladium in seabed sediment samples, gallium and indium in rock and sediment samples, based on laser-induced fluorescence combined with graphite electrothermal atomization and time-gate technique.     

Rapid RP-LC Method with Fluorescence Detection for Analysis of Fexofenadine in Human Plasma

A rapid and sensitive reversed-phase high-performance liquid chromatographic method for analysis of fexofenadine in human plasma has been developed and optimized. The analytes were extracted from biological samples by solid-phase extraction on hydrophilic–lipophilic balance cartridges. LC separation was performed on a C₁₈ analytical column (125 mm × 4 mm i.d., 5-μm particles) with 42:58 (v/v) acetonitrile–water adjusted to pH 2.7 with 85% orthophosphoric acid as mobile phase. Fluorescence detection was performed with excitation at 230 nm and emission at 290 nm. The total time for chromatographic separation was 7 min. The method was validated in accordance with EU guidelines by analysis of plasma samples fortified with fexofenadine at concentrations between 0.05 and 800 ng mL^?1. Calibration plots were linear in this range. Mean recovery was typically 94.03% and the detection limit was 0.05 ng mL^?1. The time required for quantitative analysis is shorter than that required by other methods.     

Rapid RP-LC Method with Fluorescence Detection for Analysis of Fexofenadine in Human Plasma

A rapid and sensitive reversed-phase high-performance liquid chromatographic method for analysis of fexofenadine in human plasma has been developed and optimized. The analytes were extracted from biological samples by solid-phase extraction on hydrophilic–lipophilic balance cartridges. LC separation was performed on a C₁₈ analytical column (125 mm × 4 mm i.d., 5-μm particles) with 42:58 (v/v) acetonitrile–water adjusted to pH 2.7 with 85% orthophosphoric acid as mobile phase. Fluorescence detection was performed with excitation at 230 nm and emission at 290 nm. The total time for chromatographic separation was 7 min. The method was validated in accordance with EU guidelines by analysis of plasma samples fortified with fexofenadine at concentrations between 0.05 and 800 ng mL⁻¹. Calibration plots were linear in this range. Mean recovery was typically 94.03% and the detection limit was 0.05 ng mL⁻¹. The time required for quantitative analysis is shorter than that required by other methods.

     

Solid-Phase Extraction and LC with Fluorescence Detection for Analysis of PAHs in Rainwater

The efficiency of extraction of polycyclic aromatic hydrocarbons (PAHs) from rainwater by solid-phase extraction (SPE) with three different types of cartridge, and analysis by high-performance liquid chromatography with fluorescence detection, are discussed in this paper. Three cartridges were investigated but only one was suitable. After equilibration in a desiccator for 65–80 h or in ambient air for 90–100 h the SPE cartridges were activated with 5 mL dichloromethane then 5 mL 2-propanol. The volume of sample passed through the cartridges was 50 mL; after loading of the sample the cartridges were dried under vacuum for approximately 20 min by application of a pressure of 15 mbar to the SPE manifold. The PAHs were eluted with 5 mL dichloromethane–hexane, 50:50 (v/v). The flow rate used for conditioning, sample loading, and elution was 2.5 mL min⁻¹, achieved by application of a pressure of 6 mbar. For analysis of PAHs in rainwater, recovery was between 67 and 99%, the relative standard deviation varied between 2 and 5%, and the detection limits of the method were less than 16.9 ng L⁻¹ for several PAHs. These optimum conditions were used for analysis of rainwater collected between June 2002 and May 2003 at two sites in Alsace (eastern France) and 17 PAHs were quantitatively determined. Concentrations varied between 1.6 and 968.1 ng L⁻¹.     

痕量糖-8-氨基芘-1,3,6-三磺酸衍生物的毛细管电泳-激光诱导荧光分析

以芘为原料经磺化、氨化合成了８－氨基芘－１,３,６－三磺酸钠盐（ＡＰＴＳ）,建立了相应的纯化方法,考察了多种条件对还原单糖衍生效率的影响,研究单糖及葡聚糖水解寡糖－ＡＰＴＳ衍生物的毛细管电泳－激光诱导荧光分离与检测,单糖的检测限在ａｍｏｌ（１０＾－１８）水平。     

A Novel Fluorescence Immunoassay Based on Two-time Amplified Fluorescence Signal by Hemin and Magnetic Nanoparticles for the Detection of Antigen

Abstract

A novel, selective, and sensitive magnetic-mimetic enzyme fluorescence immunoassay method for antigen detection has been developed by taking advantage of a magnetic separation process and the amplification feature of the hemin label. This method is based on a twice amplified fluorescence signal. The signal is first amplified due to the ultrasmall size and the high surface-to-volume ratio of the silica-coated magnetite nanoparticles, which enable the nanoparticles to carry much more antibodies. Second, the mimetic enzyme (hemin) as a labeling reagent catalyzes the reaction of p-hydroxyphenyl acetic acid and H₂O₂ can further amplify the fluorescence signal. This protocol was also evaluated for a sandwich-type immunoassay of human IgG, and the calibration graph for human IgG was linear over the range of 0–100 ng mL^?1 with a detection limit of 9.8 ng mL^?1. This method can easily separate magnetic nanoparticles from the solution, which simplified the process and played a promising role for various applications in immunoassay.     

Liquid Chromatography with Fluorescence Detection in the Analysis of Biological Fluids

ABSTRACT

Liquid chromatography with fluorescence detection is well suited to the analysis of biological fluids, as it combines both selectivity and sensitivity. The determinations are not limited to fluorescent compounds, as non-fluorescent substances can be converted to fluorescent derivatives by appropriate reactions. As a consequence of progress in methodology and of the development of new reagents, a great number of biological substances and drugs can now be successfully analyzed by this technique. Reliable automated procedures using pre-column derivatization are available, in particular for the analysis of amino acids and amines. In addition, systems using short columns, reduced particle size of the stationary phase and ultramicro detector cells represent a promising approach to the analysis of very small volumes of sample.     

Bio‐Inspired Photonic‐Crystal Microchip for Fluorescent Ultratrace Detection

Ultratrace detection attracts great interest because it is still a challenge to the early diagnosis and drug testing. Enriching the targets from highly diluted solutions to the sensitive area is a promising method. Inspired by the fog‐collecting structure on Stenocara beetle’s back, a photonic‐crystal (PC) microchip with hydrophilic–hydrophobic micropattern was fabricated by inkjet printing. This device was used to realize high‐sensitive ultratrace detection of fluorescence analytes and fluorophore‐based assays. Coupled with the fluorescence enhancement effect of a PC, detection down to 10^?16 mol L^?1 was achieved. This design can be combined with biophotonic devices for the detection of drugs, diseases, and pollutions of the ecosystem.