基于水溶性共轭聚合物的蛋白质荧光传感器

化学和生物传感器研究领域对新传感材料的开发越来越依赖.探讨了基于荧光信号放大共轭聚合物的蛋白质传感器的最新进展;共轭聚合物可作为高效电子/能量传递载体这一特性是其高灵敏度检测/信号放大的根源;详细介绍了数种传感策略.     

Label-free selective sensing of Pb2＋ lead（II） sensors based on the aggregation of a pyrene fluorescent probe

In the present work, we report a label-free fluo- rescence turn-on approach for the sensitive and selective sensing of Pb2＋. Pyrene with one positive charge was used as the fluorescent probe, and thrombin aptamer （TBA）, which was a G-rich oligonucleotide, was employed to form G-quadruplex with lead（II）. When TBA and Pb2＋ were mixed with lead（II） in an aqueous solution, it was folded into a stable G-quadruplex. Subsequently, a single-stranded nucleic acid-specific nuclease S1 was added. The G-quad- ruplex stabilized by Pb2＋ lead（II） had markedly a significant resistant ability to nuclease S1 digestion. However, in the absence of Pb2＋ lead（II）, no quadruplex or less stable quadruplex was formed and TBA was digested by nuclease S1 in 3 min under the optimized experimental conditions. Finally, pyrene probe was Pb2＋ lead（II）. Electrostatic mixed with oligonucleotide in interactions between oligonu- cleotide （a polyanion） and the probe induced the aggregation of the probe, which in turn produced strong emission of the strong pyrene excimer emission. The intensity of the induced excimer emission was directly proportional to the amount of Pb2＋ added. Our approach shows good selectivity and sen- sitivity for the detection of Pb2＋ with a limit of detection limit as low as 800 nmol/L.     

Preparation and Characterization of Fluorescence Labeling of Magnetic Carbon Nanotubes

In this paper,we present a novel method to fluorescently label magnetic carbon nanotubes by combining a non-ionic surfactant Tween 20 and a fluorescein isothiocyanate(FITC) commonly used in biological experiments.The samples were characterized using transmission electron microscopy(TEM),UV-Vis absorption spectrum(UV-Vis),vibrating sample magnetometer(VSM) and fluorescence spectra(FL).     

2-水杨酰腙丙酸荧光猝灭法快速测定天然水中的痕量铜

本文利用Cu2 对2-水杨酰腙丙酸(SHPA)荧光的猝灭作用，建立了快速测定天然水中痕量铜的新方法。实验结果表明，在中性介质中，SHPA的荧光强度与Cu2 的浓度呈良好的线性关系，相关系数(r)为0.9974，Cu2 的检出限为0.36 μmol/L，线性范围为(0.7 – 9.3) μmol/L。本方法用于模拟天然水水样中Cu2 的测定，RSD = 2.41%。     

靛蓝二磺酸钠与脱氧核酸的相互作用研究

本文采用紫外光谱、荧光光谱等手段对靛蓝二磺酸钠与小牛胸腺脱氧核糖核酸（ctDNA）的作用方式进行了研究，发现核糖对靛蓝二磺酸有较强的荧光猝灭作用，并测定了其反应的结合常数，结合位点数和基本热力学参数等，紫外吸收光谱证实了靛蓝二磺酸钠通过嵌插作用与核酸结合．     

邻苯二甲酸与部分稀土二元配合物的合成及其荧光性质

合成了邻苯二甲酸与部分稀土二元配合物。测定了该配合物的Ｘ－射线粉末衍射，红外光谱和荧光光谱。研究了ＴＢ（ＨＬ）３和掺杂Ｔｂ的Ｙ１－ｘ（ＨＬ０３：Ｔｂｘ，Ｌａ１－ｘ（ＨＬ）３：Ｔｂｘ和Ｇｄ１－ｘ（ＨＬ）３：Ｔｂｘ的荧光性质。     

A designed amphiphilic peptide containing the silk fibroin motif as a potential carrier of hydrophobic drugs

The amphiphilic peptide is becoming attractive as a potential drug carrier to improve the dissolvability of hydrophobic drugs in an aqueous system; thus, facilitating drug uptake by target cells. Here, we report a novel designed amphiphilic peptide, Ac-RADAGAGARADAGAGA-NH₂, which was able to stabilize pyrene, a hydrophobic model drug we chose to study in aqueous solution. This designed peptide formed a colloidal suspension by encapsulating pyrene inside the peptide-pyrene complex. Egg phosphatidylcholine (EPC) vesicles were used to mimic cell bilayer membranes. We found that pyrene was released from the peptide coating into the EPC vesicles by mixing the colloidal suspension with EPC vesicles, which was followed by steady fluorescence spectra as a function of time. A calibration curve for the amount of pyrene released into the EPC vesicles at a given time was used to determine the final concentration of pyrene released into the lipid vesicles from the peptide-pyrene complex. The release rate of the peptide-pyrene complex was calculated to quantify the transfer of pyrene into EPC vesicles.     

中华猕猴桃蛋白酶在半极性介质中的构象变化和动力学研究

三种有机溶剂,二氧六环、二甲基甲酰胺和乙二醇,都不同程度地抑制中华猕猴桃蛋白酶催化水解赖氨酸对硝基本酯(CBZ-LYS-pNP)能力,其动力学行为符合Michaelis-Menten方程式,二氧六环的抑制作用类似于竞争性抑制类型,二甲基甲酰胺和乙二醇为非竞争性抑制,其抑制常数,分别为k_1=5.6×10~(-2)、0.58和1.60mol/L,光谱分析表明,酶在有机溶剂中,空间构象也发生了变化,随着二氧六环和二甲基甲酰胺浓度的增大,酶分子的α-螺旋度下降,无规卷曲度上升,荧光发射强度比天然酶略有增高或降低,变化的规律性不够,紫外差光谱显示,酶在6％二甲基甲酰胺中有一个243nm的负峰,此负峰随浓度的增大而增大,并略向红移,在24％二甲基甲酰胺中,负峰红移至248nm处。     

城市污水处理厂出水的三维荧光指纹特征研究

传统表征有机物含量的水质参量如化学需氧量（COD）和生化需氧量（BOD）等只能表示总量,无法展示有机物成分．荧光光谱可以作为一种新型的水质表示方法,它像指纹一样与水样一一对应,被称为水质荧光指纹．本研究采用三维荧光光谱（EEM）技术研究了城市污水荧光指纹特征．研究结果表明污水处理厂排水在Ex／EM320／400nm附近有明显的可见富里酸荧光峰,在EX／EM：272／303nm,220／301nm处具有2个明显色氨酸荧光峰,色氨酸荧光峰强度远远高于出水水样．而受纳水域在320／400nm附近没有明显的可见富里酸荧光峰．在EX／EM：272／303nm,220／301nm处色氨酸荧光峰强度远远高于出水水样．     

Dy~（3＋）-氟哌酸-十二烷基苯磺酸钠体系荧光增敏反应的研究及其分析应用

研究发现镝与氟哌酸发生荧光反应,形成荧光络合物,发射配体微扰的中心离子的M*-M型特征荧光.加入表面活性剂十二烷基苯磺酸钠生成三元离子缔合物,使体系的荧光与二元体系相比增强14倍.结果表明在最佳试验条件下,Dy3+的浓度在1.0×10-6～1.0×10-5mol/L范围内与体系的荧光强度呈线性关系,当信噪比等于3时,检测限为2.0×10-7mol/L.采用标准加入法测定了合成稀土样品中镝的含量,结果满意.