近红外荧光探针及其在生物分析中的应用进展

本文评述了自1999年以来近红外荧光探针和标记试剂及其在生物分析中的应用进展。包括:菁染料、噻嗪和噁嗪染料、含四吡咯基团染料(酞菁和卟啉)、罗丹明类、BODIPY、稀土离子配合物和量子点等。描述了它们在荧光测定和毛细管分离荧光检测以及免疫荧光分析方面的应用。引用文献75篇。     

溶剂和添加剂对尼龙6鬃丝结构形态和道明性的脸响

The transparency of nylon 6 filaments is changed by spherulites formed by Solvent Induced Crystallization (SINC) in quenching bath. The long carbon chains in alkyl diamides additives can prevent Solvent (water) Induced Crystallization so that the transparency of nylon 6 filaments is improved. The nylon 6 filaments were examined by Scanning Electron Microscopy (SEM), Small-Angle Light-Scatting (SALS), polarized microscope, light transmission rate, contact angles and others.     

Separation and Determination of Cobalt, Rhodium,Nickel and Iridium with 2-(6-Methyl-2-Benzothiazolylazo)-5-Diethylamino Phenol by HPLC

The synthesis and spectrophotometric properties of 2-(6-methyl-2-benzothiazolylazo)-5-diethylamino phenol (MBTAE), and the use of it as a precolumn derivatizing reagent to separate Co(Ⅱ), Ni(Ⅱ), Rh(Ⅲ) and Ir( Ⅳ) complexes by HPLC are discussed. When the mobile phase consists of methanol/water(90/10 Ⅴ/Ⅴ), acetate buffer with pH 4. 0 and 5×10-5 mol/L EDTA solution, the four complexes Can be separated within 9 min on ODS column. The detection limits (20 μL sample size) are 0. 059 ppb, 0. 062 ppb, 0. 053 ppb and 0. 049 ppb for Co(Ⅱ) , Rh(Ⅲ), Ni(Ⅱ) and lr(Ⅳ) respectively at a signal-to-noise ratio of 3.     

新型显色剂2,3,7-三羟基-9-(3,5-二氯-4-羟基)苯基荧光酮与钨(Ⅵ)的显色反应

研究了在阳离子表面活性剂溴化十六烷基三甲胺(CTMAB)存在下 ,新试剂2,3,7_三羟基_9_(3,5_二氯_4_羟基)苯基荧光酮(DCHPF)与钨(Ⅵ)的显色反应及光度性能 ;在0.6mol/LHCl介质中 ,试剂与钨(Ⅵ)形成化学计量比为2∶1的红色络合物 ,其最大吸收峰位于536nm波长处 ,表观摩尔吸光系数为1.28×105L·mol-1·cm-1,钨含量在0～0.4mg/L范围符合比尔定律 ;拟定分析方法用于钢样中微量钨的测定 ,结果令人满意。     

PVC/EVA-g-VC共混物的形态与加工条件和性能的关系

PVC/EVA(-14)及 PVC/EVA(-14)-g-VC的等速升温Brabender塑化曲线上有两个扭矩峰,分别标志着EVA和PVC的塑化,对应着共混形态经历的三个变化:(1)EVA塑化——PVC粉粒破碎;(2)EVA呈连续相——PVC集结粒子解体;(3)EVA呈分散相——PVC初级粒子熔化。聚合投料比(VC/EVA)越小,EVA-g-VC的塑化温度和熔体粘性越高,两个扭矩峰靠得越近。实验结果表明,EVA-g-VC与EVA相比,不仅与PVC有更好的相容性,而且有较好的均匀可混性。冲击强度的测定结果表明:EVA连续网——PVC初级粒子结构具有较高的冲击强度。VC/EVA较小时所得EVA-g-VC改性的PVC可在较宽的加工温度范围保持EVA连续网结构和较高的冲击强度。     

Design, synthesis and characterization of a novel fluorescent probe for nitric oxide based on difluoroboradiaza-s-indacene fluorophore

Nitric oxide (NO) is a gaseous, free radical, which plays a role as an intracellular second messenger and a diffusible intercellular messenger. To obtain evidence for NO function in vivo, 1,3,5,7-tetramethyl-8-(4'-aminophenyl-N-(2'-amino)-phenzyl)-difluoroboradiaza-s-indacene (TMAPABODIPY) was designed and synthesized as a fluorescent probe for nitric oxide, which features high photostability and no pH dependency over a wide pH range. The fluorescence of TMAPABODIPY itself is very strong. When TMAPABODIPY traps NO in the presence of dioxygen, the weak fluorescent triazole form is obtained, which offers the advantages of specificity, and sensitivity for direct detection of NO. The relationship was obtained between the quenching fluorescence intensity and NO concentration in the range 0.02-4.0 micromol l(-1). The detection limit is 5 nmol l(-1) (S/N = 3). The proposed method has been used to monitor the release of NO from S-nitrosocysteine, a NO-releasing agent.     

融合重建滤波器和暗特征的渗出物检测算法

针对多数视网膜渗出物提取算法检测精度不高的 问题,提出了一种融合重建滤波器和 暗特征的视网 膜渗出物检测算法。首先,对视网膜灰度图像均值滤波后应用“球形”重建滤波器移除视网 膜血管,使用列 滤波器标识出渗出物区域并阈值分割得到含有视盘和边界的渗出物区域图像。其次,在均值 滤波后的灰度 图像中检测视盘和图像边界,并根据视盘构建掩膜,接着从含有视盘和边界的渗出物区域图 像中移除视盘 和边界,然后应用 “圆盘形”重建滤波器扩充渗出物尺寸。最后,对视网膜灰度图像自适 应直方图均衡化, 阈值分割后反转灰度值得到暗特征,从扩充渗出物尺寸后的图像中移除暗特征即得到最终渗 出物图像。实验结果表明,本文算法能有效检测视网膜眼底图像中的渗出物,较现有算法具 有更高的检测精度。     

电容器在数字电路电磁兼容性设计中的应用

分析了数字电路常见的干扰种类及产生原因。根据电磁兼容性设计的要求,指出电容器在数字电路抗干扰中的重要作用,并提供了其重要参数,给出了实际电路中电容器的选择殛使用方法。     

柱前衍生反相高效液相色谱分离和测定氨基酸--用N-羟基琥珀酰亚胺-α-萘乙酸酯作衍生试剂

以N-羟基琥珀酰亚胺-α-萘乙酸酯(SINA)为氨基酸的柱前衍生试剂,反相高效液相色谱分离测定了15种氨基酸.采用含10 mmol/L pH 5.0的乙酸-乙酸钠缓冲溶液的甲醇-乙酸乙酯-水(10/2/88,V/V/V)溶液为流动相体系,分离测定了7种氨基酸;用甲醇-乙酸乙酯-水(26/2/77,V/V/V)分离测定了5种氨基酸;用甲醇-乙酸乙酯-水(45/2/53,V/V/V)分离测定了3种氨基酸.检测限均达到pmol级,且重现性好.     

Determination of catecholamines as their N-hydroxy-succinimidyl-3-indolylacetate derivatives by pre-column derivatization HPLC separation and fluorescent detection

N-Hydroxysuccinimidyl-3-indolylacetate (SIIA) is a new fluorescent derivatizing reagent with an indole ring and ¶an N-hydroxysuccinimide ester functionality. It can react with catecholamines under mild conditions to form corresponding amides, which have strong fluorescence at λ_ex/λ_em = 301 nm/¶365 nm. This paper covers the RP-HPLC separation and fluorescent determination of derivatized catecholamines with SIIA. In a mobile phase of methanol-water (36/64, v/v) containing H₃cit-Na₂HPO₄ buffer (pH = 4.00, 10 mmol/L), the derivatives of norepinephrine (NE), epinephrine (E) and dopamine (DA) were eluted within 15 min on a C₁₈ column. The detection limits were 0.043, 0.13 and 0.18 pmol, respectively, when the ratio of signal to noise (S/N) was 3. The excessive reagent is rapidly hydrolyzed to 3-indolylacetic acid (IA) that can be easily separated from derivatives.