电化学DNA生物传感器*

对特异DNA序列的检测在基因相关疾病的诊断、军事反恐和环境监测等方面均具有非常重要的意义,DNA传感器的研究就是为了满足对特异DNA序列的快速、便捷、高灵敏度和高选择性检测的需要。近年来涌现出了多种传感策略,根据检测方法的不同可以大致分为光学传感器、电化学传感器、声学传感器等。由于电化学检测方法本身所具有的灵敏、快速、低成本和低能耗等特点,电化学DNA传感器已成为一个非常活跃的研究领域并在近几年中得到了快速发展。本文概括了近年来在DNA传感器的重要分支——电化学DNA传感器领域内的一些重要进展,主要包括DNA探针在传感界面上的固定方法和各种电化学DNA杂交信号的检测方法。     

光电化学生物分析研究进展

光电化学生物分析是近年来新出现并发展迅速的一种分析技术,其检测原理是基于在光照下识别元件和目标分子之间的生物识别作用造成光电活性物质产生的电信号的改变,以实现对待测物的定量测定。由于其灵敏选择性检测的优点及其在生物分析中的巨大潜力,该方法吸引了较多的关注,并且在检测性能和生物传感应用等方面也取得了较大进步。本文针对光电化学生物分析中常见的四种应用领域,即直接光电化学检测、光电化学酶检测、光电化学核酸检测以及光电化学免疫分析,综述了近年来国内外在光电化学生物分析研究领域的最新进展,并对其未来发展进行了展望。     

电化学生物传感器测定甲胎蛋白的研究进展

人体血清中甲胎蛋白(AFP)含量已作为肝癌检测的重要指标,快速而准确地检测血清中的AFP含量对肝癌的早期诊断和预后都有极为重要的作用。传统的酶联免疫法存在分析时间长、前处理繁琐等不利因素。利用免疫技术与电化学检测技术结合起来的电化学免疫传感器,由于具有操作简单、灵敏度高、特异性强及成本低等特点,而得到广泛关注。本文将根据所采用的不同检测方式及修饰材料等方面对近年来电化学免疫传感器检测AFP的研究与应用进行评述,并对其发展趋势进行了展望。     

纳米电化学传感器检测微生物的研究进展

致病微生物是影响人类健康的一类重要微生物。基于纳米材料的电化学免疫生物传感器在致病微生物检测方面具有检测速度快,灵敏度高,检测下限低,成本低等优点。本文综述了几种纳米材料电化学免疫生物传感器的构建和实验研究,分析了各种纳米材料如何改善电化学传感器性能,并具体比较分析了不同纳米电化学生物传感器对各种病原微生物的检测研究,最后,对未来的发展趋势进行了展望。     

激酶检测方法的最新研究进展

激酶是生物体内一类重要的磷酸转移酶,能够催化磷酸基团由高能磷酸基团供体分子(如ATP)向特定底物分子转移。激酶不但在新陈代谢、细胞信号传导、蛋白质调控、细胞传输等过程中起着关键作用,而且在临床诊断、药物研发及疾病靶向治疗等方面也发挥着重要作用。因此,发展灵敏度高、特异性好的激酶检测方法十分必要。本文以蛋白激酶A(Protein kinase A,PKA)、酪蛋白激酶(Casein kinase-2,CKII)、T4多核苷酸激酶(T4 polynucleotide kinase,T4 PNK)为例,对近年来发展的激酶检测方法进行了综述,着重介绍了荧光分析法、单分子检测、比色法、化学发光和生物发光分析法、电化学和光电化学分析法,并对激酶检测方法的发展方向进行了展望。     

基于纳米金的ATP检测体系的研究进展

ATP是机体代谢过程中不可或缺的能量物质，参与机体的各项重要的生理生化活动，在各方面起着至关重要的作用。因此，对ATP的快速精准检测具有重要的临床意义。纳米金（AuNPs）因优良的光学特性、催化活性、生物相容性等特点，被广泛应用于构建ATP检测体系。本文综述了目前AuNPs应用于ATP检测的研究进展，如比色检测、荧光分析、电化学检测、电化学发光检测、化学发光检测以及表面增强拉曼散射等，比较了各种检测方法的优点与不足，并对AuNPs在ATP检测应用中面临的挑战和机遇做了展望。     

半胱氨酸传感器的研究进展

半胱氨酸(Cys)作为人体中一种不可缺少的氨基酸,对维持蛋白质功能和新陈代谢等方面起着重要作用,因此半胱氨酸的检测与传感器的开发也显得十分重要。本文综述了近些年来半胱氨酸传感器的研究进展,对半胱氨酸电化学传感器、比色传感器以及荧光传感器等的研制与应用方面进行了阐述和评价,并对半胱氨酸传感器的发展前景进行了展望。     

核酸等温扩增技术在电化学生物传感器中的应用

生物分子检测在临床诊断、基因治疗、基因突变分析等方面变得日益重要,因而,建立简单、快速、灵敏的检测方法具有重要意义。近年,电化学生物传感器因其简单、便携、易操作、成本低等优势在生物分子检测的研究中备受关注。为了提高检测方法的灵敏度,不同的核酸等温扩增技术被应用于电化学生物传感器的构建中。本文简单介绍了电化学生物传感器的工作原理,着重综述了几种主要应用于电化学传感器中的核酸等温扩增技术,同时比较了各方法的优缺点。     

基于纳米材料的电化学生物传感器检测微生物的研究进展

致病微生物是影响人类健康的一类重要微生物。基于纳米材料的电化学生物传感器在致病微生物检测方面具有检测速度快、灵敏度高、检出限低、成本低等优点。本文对几种基于纳米材料的电化学生物传感器的研究进展进行了介绍,分析了各种纳米材料如何改善电化学传感器性能,并对各种传感器的检测结果进行了比较分析;最后,对该领域未来的发展趋势进行了展望。     

酶标记的电化学DNA传感器

对特异DNA序列的检测,在基因相关疾病的诊断、军事反恐和环境监测等方面均具有非常重要的意义.DNA传感器的研究就是为了满足对特异DNA序列的快速、便捷、高灵敏度和高选择性检测的需要.近年来涌现出多种传感策略,根据其检测方法大致可以分为光学传感器、电化学传感器和声学传感器等.由于电化学检测方法本身所具有的灵敏、快速、低成本和低能耗等特点,电化学DNA传感器已成为一个非常活跃的研究领域并得到了快速发展.     

A competitive immunochromatographic assay for testosterone based on electrochemical detection

An immunochromatographic assay using nitrocellulose membrane was combined with electrochemical detection using an electrode chip in order to quantitatively detect testosterone as a model analyte. The electrode chip consisted of a gold working electrode, a counter electrode and a pseudo-reference electrode, all fabricated on the bottom of a 3.2 mm × 3.2 mm well. Competitive immunoreactions on the membrane were initiated by flowing a solution containing testosterone and horseradish peroxidase (HRP)-labeled testosterone (a competitor) over the membrane. Prepared membrane was placed in a solution containing ferrocenemethanol (FcOH) and H₂O₂ in the well of the electrode chip, and the enzyme reaction was detected by amperometry. Labeled HRP captured on the membrane catalyzed the oxidation of FcOH to the oxidized form FcOH⁺, which was reduced electrochemically by the electrode chip. The electrochemical response of the reduction current decreased with increasing concentration of testosterone over the range 1–625 ng/ml.     

Voltammetric Behavior of Testosterone on Bismuth Film Electrode: Highly Sensitive Determination in Pharmaceuticals and Human Urine by Square‐Wave Adsorptive Stripping Voltammetry

In this paper, an electrochemical application of bismuth‐film electrode (BiFE) fabricated via ex‐situ electrodeposition onto a glassy carbon electrode for testosterone determination was investigated in aqueous and aqueous/surfactant solutions. In cyclic voltammetry, the compound showed one irreversible and adsorption‐controlled reduction peak. The BiFE revealed good linear response in the examined concentration range of 1 to 45 nmol L^?1 testosterone in Britton? Robinson buffer, pH 5.0 containing 3 mmol L^?1 cetyltrimethylammonium bromide. The limit of detection was 0.3 nmol L^?1 (0.09 ng mL^?1). Finally, the BiFE was satisfactorily applied for quantitation of testosterone in both pharmaceutical (oil‐based ampoule) and biological (human urine) samples.     

An Electrochemical Biosensor Platform for Testing of Dehydroepiandrosterone 3‐Sulfate (DHEA−S) as a Model for Doping Materials

Endogenous steroids such as dehydroepiandrosterone (DHEA) and dehydroepiandrosterone 3‐sulfate (DHEA?S) have commonly used as doping materials by athletes and to date novel techniques are needed for detection of these molecules. In this study, antibody‐based electrochemical biosensor has developed for testing level of the DHEA?S. For this aim, gold surfaces were initially modified with cysteamine (Cys) and then, DHEA?S antibody was immobilized on the surface via glutaraldehyde (GA) as a crosslinking agent. The stepwise modification of electrode surface was monitored by using various electrochemical techniques such as cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Linear range was determined as 2.5–100 ng/mL DHEA?S using differential pulse voltammetry (DPV) technique, as well. Moreover, repeatability (±S.D.), coefficient of variation (%) and limit of detection (LOD) values were calculated as 0.033, 1.030 and 3.971, respectively. Also, DHEA?S in synthetic serum and urine samples were successfully determined with standard addition method and confirmation analysis were performed with liquid chromatography quadrupole‐time of flight mass spectrometry (LC‐QTOF/MS) system. The selectivity was studied with the addition of some interfering molecules (testosterone, bovine serum albumin (BSA), cholesterol, uric acid, lactic acid, codein (COD), ascorbic acid, DHEA). Consequently, this work is proposed as practical, innovative and cost‐effective technique that can be easily adapted for the miniaturized form for the analysis of other doping substances as well as DHEA?S for the future works.     

Analysis of testosterone in human urine using molecularly imprinted solid-phase extraction and corona discharge ion mobility spectrometry

Analysis of testosterone was accomplished using corona discharge ion mobility spectrometry. Molecular imprinted polymer was used for the extraction and pre-concentration of testosterone. Analytical parameters including precision, dynamic range and detection limit were obtained. The linear dynamic range was from 10 to 250 ng/mL and the limit of detection was 0.9 ng/mL. The proposed method was used for analysis of testosterone in urine samples. A urine sample from a 3-year-old girl was used as the blank. The RSD was below 10%. The obtained results from the method were also compared with the standard method for analysis of testosterone using SPE-HPLC analysis. The results demonstrate the accuracy of the method.     

Boldenone, testosterone and 1,4-androstadiene-3,17-dione determination in faeces from horses, untreated and after administration of androsta-1,4-diene-3,17-dione (boldione)

Faeces, which could be a potential alternative medium for doping control, have been used for the detection of 1,4-androstadiene-3,17-dione administration to the horse. Semi-quantitative analyses of 1,4-androstadiene-3,17-dione, testosterone, 17alpha- and 17beta-boldenone have been conducted in pre- and post-administration faeces, and in controls (untreated stallions, geldings and mares). Sample preparation comprised diethyl ether extraction, lipid removal, HPLC purification and derivatisation. 1,4-Androstadiene-3,17-dione, testosterone, 17alpha- and 17beta-boldenone were analysed by GC-EI/MS/MS. Quantitative limits of detection were 0.1 ng/g for 1,4-androstadiene-3,17-dione, and 0.025 ng/g for testosterone, 17alpha- and 17beta-testosterone. In post-administration samples from geldings and mares, peak levels of 1,4-androstadiene-3,17-dione, 17alpha-, 17beta-boldenone and testosterone were attained 24 h after administration. In untreated geldings and mares (in di- or anoestrus), 17alpha- and 17beta-boldenone and testosterone were not detected. Faeces from females in oestrus had detectable levels of boldenone isomers and testosterone. 1,4-Androstadiene-3,17-dione was undetectable in faeces collected from untreated horses, but the presence of this androgen was recently reported in faeces from untreated swine and it would therefore be advisable to check for its possible presence in a larger number of individual faecal samples.     

Determination of phenolic antioxidants in pharmaceutical formulations by liquid chromatography and migration study on HDPE packagings

Summary The performance of UV diode-array, spectrometric and electrochemical detectors was compared in the chromatographic analysis of trace amounts of six phenolic antioxidants. Quantitative validation was undertaken; the linearity range was wider using UV detection although the limits of detection were lower with electrochemical detection. UV detection was applied both to identification of an antioxidant in a hydrophilic suspension and to a migration study.     

毛细管电泳与芯片毛细管电泳的双检测技术

综述了毛细管电泳和芯片毛细管电泳的3种双检测技术,包括荧光-散射等光学双检测技术、安培-非接触电导等电化学双检测技术和荧光-非接触电导等光电联用双检测技术.介绍了3种双检测方法的仪器的检测原理及应用,并展望了双检测技术的发展前景.引用文献54篇.     

Determination of testosterone propionate in human plasma by gas chromatography-mass spectrometry

A specific, sensitive and accurate quantitative analysis of testosterone propionate in human plasma was developed using gas chromatography-mass spectrometry-selected-ion monitoring. For the calculation of testosterone propionate in plasma, peak height ratios were measured by selected-ion monitoring performed on the molecular ions of the trifluoroacetyl derivative of testosterone propionate (m/z 440) and testosterone propionate-19,19,19-d3 (m/z 443). The sensitivity of the method was judged from the lower limit of the detection of the mass spectrometer which was at 20 pg. The inter-assay coefficients of variation and relative error at a concentration of 1.31 ng/ml of plasma were 5.47% and -2.3%, respectively. The method described was applied to the determination of plasma concentrations of testosterone propionate-19,19,19-d3 following an intramuscular dose of testosterone propionate-19,19,19-d3 in a healthy male volunteer.     

Application of pentafluorophenyl hydrazine derivatives to the analysis of nabumetone and testosterone in human plasma by liquid chromatography–atmospheric pressure chemical ionization–tandem mass spectrometry

Two carbonyl compounds, nabumetone and testosterone, were derivatized with pentafluorophenyl hydrazine (PFPH) and analyzed by atmospheric-pressure chemical-ionization mass spectrometry. The PFPH derivatives underwent dissociative electron capture in negative-ion APCI (ECAPCI) and gave intense [M–20]^– ions in the mass spectra. In positive-ion APCI, the PFPH derivatives underwent efficient protonation and gave intense [M+H]⁺ ions in the mass spectra. In CID, the major product ions of the [M–20]^– ions in ECAPCI corresponded to the partial moiety of PFPH. In contrast, the major product ions of [M+H]⁺ corresponded to the partial moiety of the analyte. By using selected reaction monitoring (SRM) detection, low pg of nabumetone (1 pg) and testosterone (7 pg) could be detected in both ECAPCI and positive-ion APCI. In comparison with the detection limits (SRM) of the underivatized analytes, use of the PFPH derivatives resulted in 2500-fold and 35-fold sensitivity enhancements for nabumetone and testosterone, respectively. The PFPH derivatives were applied to the analysis of nabumetone and testosterone in human plasma by both ECAPCI and positive-ion APCI and were found to enable detection of 0.1 ng mL^–1 nabumetone in spiked plasma. For testosterone, endogenous testosterone in female plasma was detected in both ECAPCI and positive-ion APCI.