一种基于共振角度测量的小型SPR传感器

合成了一种光学有机玻璃并进行了性能表征，用其制作了一种不规则六面体光学棱镜，采用这种光学棱镜，以发光二极管为光源，线阵CCD为检测器，组装了一种共振角度同时测量的小型SPR传感装置，讨论了影响该传感器灵敏度，分辨率和线性范围的因素，将其用于乙醇和磷酸二氢钾的检测，获得了较好的结果。     

γ-干扰素DNA传感器组装过程的表面等离子体子共振研究

自行设计并组装了一套简便实用的多波长表面等离子体子共振DNA传感装置,用于γ-干扰素DNA的检测。以人工合成γ-干扰素(interferongamma,IFN-γ)寡聚核苷酸片段作为DNA探针,用化学法标记生物素探针,利用生物素-亲和素系统相互作用在传感器表面固定DNA探针,使用该SPR传感装置实时监测了DNA探针的固定过程及DNA杂交反应的进行。用于IFN-γ寡聚核苷酸的检测,测定范围为50-400ng/mL;用于IFN-γ的聚合酶链反应(polymerasechainreaction,PCR)扩增产物的检测,其测定范围为5-40ng/mL。同时研究了DNA传感器的稳定性、可逆性及干扰情况。实验结果表明,该传感器可成功地用于检测目的DNA。     

樱桃红共振光散射光谱法测定牛血清白蛋白

研究了以樱桃红为共振光散射探针测定牛血清白蛋白的分析方法。在pH 3.58的BR缓冲溶液中,樱桃红与牛血清白蛋白(BSA)相互作用形成复合物,导致共振光散射(RLS)光谱明显增强,最大RLS峰位于340 nm处。由此建立检测痕量BSA的新方法。在优化实验条件下,RLS强度与BSA浓度的线性范围为1.0～60.0μg/mL,检出限为0.15μg/mL。方法可用于牛尿样品的分析。     

小檗碱共振光散射法测定脱氧核糖核酸

研究了小檗碱与DNA作用的共振光散射光谱，在pH＝2.0-2.8的范围内，DNA的加入导致小檗碱共振光散射的增强，在308nm处，存在一共振光散射增强峰，其强度与DNA的浓度呈线性关系，据此建立了一种测定DNA的共振光散射法。该方法的线性范围为0－600μg/L，相关系数为0.9972，检出限为19.9μg/L。将该方法用于混合样品中DNA的测定。结果令人满意。     

固定光路可变焦宽调角表面等离子共振成像装置

设计了一种折反式棱镜耦合单元, 用于简化表面等离子共振系统的角度调节操作, 并基于此单元构建了固定光路可变焦宽调角表面等离子共振成像装置. 该装置通过旋转折反式棱镜耦合单元即可实现角度调节, 调节范围可达40°~80°, 结合1~2倍的变焦成像系统, 可对1~4 cm²传感芯片成像, 且可分辨至少3600 Point/cm². 以蔗糖溶液为研究对象, 考察了该装置的灵敏度, 结果表明其灵敏度可达7×10^-6 RIU(Refractive index unit), 共振角与折射率的线性相关系数为0.99953. 将该装置用于研究抗牛血清白蛋白抗体与其它蛋白的实时相互作用, 所得结果与理论相符. 该表面等离子共振成像装置将在实时并行分析方面具有广阔的应用前景.     

共振瑞利散射法测定棉子糖含量的研究及应用

在pH=9.90的B-R缓冲溶液中,棉子糖能显著降低FeCl3的共振瑞利散射光强度,基于此建立了一种测定棉子糖含量的新方法。在优化实验条件下,FeCl3的共振瑞利散射光谱强度的减少值与棉子糖浓度呈良好的线性关系,线性范围为0.75~3.0μg/mL,相关系数(R=0.9975)。该方法可用于保健食品中棉子糖含量的测定。     

共振散射法测定中草药中的微量铬

研究了在H2SO4介质中,Cr(Ⅵ)与碘化物和淀粉形成离子缔合物的共振光散射增强现象,拟定了一种新的测定Cr(Ⅵ)的共振光散射方法,通过实验确定了溶液中Cr(Ⅵ)浓度与散射光强度之间的关系,在λex＝λem＝290 nm处,共振光散射最强,且共振光散射强度与Cr(Ⅵ)浓度呈线性关系,该方法简便快速,线性范围为34～400 μg/L,检出限为6.7 μg/L,可用于中草药样品中铬的测定.     

基于聚多巴胺纳米粒子的荧光共振能量转移法检测microRNA

基于聚多巴胺纳米粒子(PDA NPs)对Cy5标记单链DNA(Cy5-ssDNA)探针的荧光猝灭效应以及脱氧核糖核酸酶Ⅰ(DNaseⅠ)选择性切割DNA/RNA杂合结构中单链DNA的特性,建立了一种用于微小核糖核酸(miRNA)检测的新型恒温信号放大方法.在优化的实验条件下,体系的相对荧光强度(FR)与miR-21浓度的对数值成正比;对miR-21检测的线性范围为10 pmol/L~100 nmol/L,检出限达7 pmol/L.血清加标实验结果表明,该方法可用于生理环境下miR-21的检测.     

阴离子表面活性剂与蛋白质的共振瑞利散射及分析应用

在酸性条件下，蛋白质与阴离子表面活性剂结合形成离子缔合物，使共振瑞利散射(RRs)急剧增强。以十二烷基硫酸钠与牛血清白蛋白反应体系为例，研究了相应的光谱特征，影响因素和适宜的反应条件。在此条件下，不同蛋白质在0-5mg／L或0—l0mg／L范围内与散射强度呈直线关系。方法灵敏度较高，其检出限在17-180μg/L之间，线性范围宽，选择性和重现性较好，可用于多种蛋白质的测定。本法用于合成样品以及人血清样品中蛋白质量的测定，结果满意。     

声光可调滤光片表面等离子体子共振传感器的研究

自行设计并组装了一套以声光可调滤光片(AOTF)为波长选择系统的波长检测型表面等离子体子共振(SPR)传感器装置,介绍了AOTF的特点和性能.研究了传感器对乙醇、葡萄糖和蔗糖的响应特性,三者的线性范围分别为5%～60%(体积分数),0.028～0.280和0.014～0.140mol/L.并对葡萄糖和蔗糖的混合溶液进行了分析.实际样品的测定结果与国家标准方法的测定值相符合     

Pyrene-Capped CdSe@ZnS Nanoparticles as Sensitive Flexible Oxygen Sensors in Non-Aqueous Media

A flexible, highly sensitive sensor of oxygen in non-aqueous solvents is described. It consists of CdSe/ZnS nanoparticles decorated with a considerable number of pyrene units, thus making the formation of the pyrene excimer possible. The emission of the pyrene excimer and that of the nanoparticle are suitably separated from each other and also from the excitation wavelength. This sensor can be applied as a ratiometric oxygen sensor by using the linear response of the pyrene excimer lifetime combined with the linear response of the nanoparticle excited state lifetime. This nanohybrid has been assayed in seven media with different dielectric constants and viscosities over the whole oxygen concentration range. In addition, the sensor versatility provides an easy way for monitoring oxygen diffusion through systems.     

Molecularly imprinted polymer-based electrochemical sensor for the sensitive detection of glyphosate herbicide

A sensitive electrochemical molecularly imprinted sensor was developed for the detection of glyphosate (Gly), by electropolymerisation of p-aminothiophenol-functionalised gold nanoparticles in the presence of Gly as template molecule. The extraction of the template leads to the formation of cavities that are able to specifically recognise and bind Gly through hydrogen bonds between Gly molecules and aniline moieties. The performance of the developed sensor for the detection of Gly was investigated by linear sweep voltammetry using a hexacyanoferrate/hexacyanoferrite solution as redox probe, the electron transfer rate increasing when concentration of Gly increases, due to a p-doping effect. The molecularly imprinted sensor exhibits a broad linear range, between 1 pg/L and 1 µg/L and a quantification limit of 0.8 pg/L. The selectivity of the proposed sensor was investigated towards the binding of Gly metabolite, aminomethylphosphonic acid, revealing excellent selectivity towards Gly. The developed sensor was successfully applied to detect Gly in tap water samples.     

Electrochemical sensor for the detection of estradiol based on electropolymerized molecularly imprinted polythioaniline film with signal amplification using gold nanoparticles

A sensitive electrochemical molecularly imprinted sensor was developed for the detection of estradiol_, by electropolymerization of p-aminothiophenol functionalized gold nanoparticles in the presence of estradiol as template molecule. The extraction of the template leads to the formation of cavities that are able to recognize and bind estradiol with high affinity. The performance of the developed sensor for the detection of estradiol was investigated by linear sweep voltammetry using a hexacyanoferrate/hexacyanoferrite solution as redox probe. The molecularly imprinted sensor exhibits a broad linear range, between 3.6 fM and 3.6 nM and a limit of quantification of 1.09 fM. Compared to the non-imprinted sensor, the imprinted sensor exhibits high affinity for the binding of estradiol. Moreover, selectivity studies, performed towards binding of testosterone, a hormone with similar chemical structure, proved high sensor selectivity. Furthermore, the molecularly imprinted sensor was applied for the analysis of spiked river samples with good recoveries.     

Covalently immobilized aminonaphthalimide as fluorescent carrier for the preparation of optical sensors

By replacing the hydrogen of the 4-amino group of a 4-amino-1,8-naphthalimide derivative with an N-acryloxyethyl group, the fluorophore has been covalently immobilized on an optical sensor surface by UV photopolymerization. The optical sensor obtained can be used for the determination of picric acid. The linear range and detection limit of the sensor are 9.80x10(-7)-1.96x10(-4) mol L(-1) and 7.1x10(-7) mol L(-1), respectively. Leaching of the fluorophore from the membrane is effectively prevented by covalent immobilization, resulting in a sensor with a relatively long lifetime. The response time of the sensor is short, and the reproducibility and reversibility are good. The sensor has been used for the indirect determination of the chloroquine content of pharmaceutical tablets.     

A Novel Microbial Sensor for Anionic Surfactant Determination

Abstract

A novel whole cell biosensor was constructed for detection of anionic surfactants in an aquatic environment. The sensor response to linear alkyl benzene sulfonates was linear up to 6 mg l^?1 which is a range suitable for the detection of anionic surfactant concentration in polluted river water. Under optimum conditions, the sensor response time was less than 15 min. Anionic surfactant analysis was rapid and convenient and did not require organic reagents which are harmful to an environment.     

An amperometric ethanol sensor based on foam nickel electrode

An amperometric sensor using foam nickel electrode as the working electrode for the measurement of ethanol in alkaline solution has been developed. Cyclic voltammetry and chronoamperometry are employed to analyze electrochemical behavior of the electrode. The results show that the oxidation of ethanol is more efficient on the foam nickel electrode than that on the nickel foil electrode. The sensor exhibits a good linear relationship between response current and ethanol concentration in the range of 4 to 1400 ppm with a detection limit of 0.8 ppm. The sensitivity and the response time of the sensor are 4.63 μA/ppm and 10 s respectively. Additionally, the sensor has 60 days shelf-life time at least.     

Cetyltrimethylammonium Bromide(CTAB)-Ionic Liquid Composite Modified Electrode for Sensitive Cyclic Voltammetric Determination of Bisphenol A

A sensitive electrochemical sensor for determining bisphenol A(BPA) was designed. The sensor was a glassy carbon electrode modified with the surfactant cetyltrimethylammonium bromide and the ionic liquid 1-decyl-3-methylimidazolium tetrafluoroborate. The ability of the new sensor to measure BPA was investigated in cyclic voltammetry experiments. Under optimized conditions, the sensor gave a linear response range for BPA of 2.19×10^-7-3.28×10^-5 mol/L and a detection limit of 7.31×10^-8 mol/L(S/N=3). BPA could be determined with a lower detection limit, a wider linear range, and more sensitivity using the sensor than using other electrochemical sensors or high performance liquid chromatography with UV detection. The new sensor was used to determine BPA in tap water with recoveries of 97.5%-98.7% and a relative standard deviation <2.9%. The results show that the sensor can be used to determine trace BPA concentrations in tap water.     

微囊藻毒素分子印迹传感器的制备与应用

以邻氨基酚为单体,微囊藻毒素(MC-LR)为模板,采用循环伏安法在金电极的表面电聚合成膜分子印迹材料,制备了传感器。采用安培法对MC-LR进行检测。在制备影响条件最佳值(pH=4.5;单体/模板=1.4×108∶1;洗脱时间10 min)的基础上,对该传感器的线性范围、使用寿命、选择性等进行了研究,并与液相色谱方法进行对比,结果表明:该传感器对MC-LR具有良好的选择性和灵敏度,线性范围为0.05～0.35 mg/L;加标回收率为80%～105%;检出限为7.3μg/L。与液相色谱方法对比,当置信度为99%时,无系统误差。     

A solid-state pH transducer fabricated from a self-plasticized methacrylic-acrylic membrane for potentiometric acetylcholine chloride biosensor

A solid-state pH sensor based on a self-plasticizing film of methacrylic-acrylic copolymer was developed. The sensor was able to detect changes in pH after tridodecylamine ionophore was immobilized together with a lipophilic anionic salt. The pH sensor exhibited almost a Nemstian response (57.6 mV pH⁻¹) with a linear pH response range of 6–10. It demonstrated a fast response (<2 min) to changes in pH and good selectivity against other common cations such as sodium, potassium, magnesium, lithium, and calcium. The sensor has a shelf life of at least 30 days without an obvious deterioration in response. By depositing a layer of poly(hydroxylethymethacrylate) immobilized with enzyme acetylcholinesterase on top of the pH selective methacrylic-acrylic film, the pH sensor was able to detect acetylcholine chloride (AChCl). The linear response range of the potentiometric biosensor to AChCl was dependent on the buffer concentrations used, and for a buffer concentration less than 1 mM, the linear response range obtained was 3.98–31.62 μM. The text was submitted by the authors in English