阻抑荧光猝灭法测定环境水样中痕量砷

在H2SO4介质中,KIO4氧化吖啶黄,使体系褪色并伴随荧光猝灭,痕量的As(Ⅲ)能显著阻抑此反应,据此建立了一种新的荧光法测定痕量As(Ⅲ)。本文对该体系的实验条件进行了详细研究。在最佳条件下,方法的线性范围为5.0～400μg/L,检出限为2.4μg/L。方法已用于环境水样中痕量As(Ⅲ)的测定,加标回收率为94.2%～102.6%。     

Determination of azaarenes in oils using the LC‐APCI‐MS/MS technique: New environmental toxicant in food oils

A novel method to determine of azaarenes in refined and cold‐pressed vegetable oils and animal fats is reported. The method may be used to determine eight most important acridine derivatives (benz[a]acridine, dibenz[a,i]acridine, benz[c]acridine, dibenz[a,j]acridine, 7,9‐dimethylbenz[c]acridine, dibenz[a,h]acridine, dibenz[a,c]acridine, dibenz[c,h]acridine) at a high sensitivity (LOQ in the 2–25 ng kg^?1 range), high analyte recovery rates (70.7–98.7%), sufficient linearity within the studied concentration range (r > 0.97). The method is fast, simple, and needs no expensive clean‐up procedures to successfully determine the analytes. Azaarene concentration in the studied oil samples ranged from 2 to 250 ng kg^?1. Benz[a]acridine and dibenz[a,j]acridine were the compounds found most commonly and at the highest concentrations. The observed concentrations most probably reflected levels of environmental contamination of raw materials used to produce the analyzed oil/fat samples.     

吖啶黄-纳米金荧光共振能量转移体系增敏法检测高半胱氨酸

以吖啶黄(Acridine Yellow,AY)为供体,纳米金(AuNPs)为受体建立了荧光共振能量转移(FRET)的新体系。体系中AY以非共价的方式吸附在AuNPs上,两者之间发生了有效的能量转移,导致AY的荧光猝灭。由于高半胱氨酸(Homocysteine,Hcys)和纳米金之间可以形成很强的Au-S键,使AY从AuNPs表面释放,进而使体系的荧光恢复。基于增强的荧光信号建立了检测高半胱氨酸的新方法。在最优化的条件下,检测高半胱氨酸的线性范围为5.0×10-10—1.5×10-8mol/L,检出限为0.2×10-10mol/L。     

以吖啶橙为荧光探针研究士的宁和布鲁辛与小牛胸腺DNA的相互作用

以吖啶橙(AO)为荧光探针,应用各种光谱法和热力学方法研究士的宁和布鲁辛与小牛胸腺DNA(ct-DNA)的相互作用情况。实验结果表明,在模拟人体生理环境下,把士的宁和布鲁辛这两种药物加入到DNA-AO体系中时,DNA-AO的光谱特征发生了明显的变化:在200nm和260nm处的紫外光谱吸收峰均有明显的减色效应,但没有红移和蓝移现象,表明药物与DNA不是典型的嵌插作用结合;DNA-AO的荧光光谱被药物显著的猝灭,根据Stern-Volmer方程可计算出士的宁和布鲁辛与DNA的成键常数分别是9.85×103L.mol-1和4.76×103L.mol-1。热变性温度,离子强度法和黏度法进一步证明药物与DNA不是嵌插结合,而是以沟槽作用的方式结合。     

吖啶黄与脱氧核糖核酸加成反应机理及其在微量DNA测定中的应用

研究了微量脱氧核糖核酸与吖啶黄的加成反应,并对反应条件作了优化,基于在pH6.5的B-R缓冲溶液中,脱氧核糖核酸(DNA)浓度与吖啶黄最大吸收波长444 nm处的吸光度线性降低的关系,建立了测定微量DNA的方法。在小于8.0 mg.L-1浓度范围内呈现良好的线性关系,相关系数为0.999 8,对3个模拟试样中DNA含量作了测定,结果的RSD值及回收率的测定结果分别在1.4%~3.0%及98.3%~104.0%之间。对此加成反应的机理也作了初步探讨。     

Synthesis of N,N‐Dialkyl‐9‐oxoacridine‐10(9H)‐carbothioamides via the Reaction of (2‐Halophenyl)(2‐isothiocyanatophenyl)methanones with Secondary Amines,Followed by Cyclization with NaH

The first preparation of acridin‐9(10H)‐ones carrying a tertiary thiocarbamoyl group at C(10), i.e., N,N‐dialkyl‐9‐oxoacridine‐10(9H)‐carbothioamides 9 , is described. The method is based on the reaction of (2‐halophenyl)(2‐isothiocyanatophenyl)methanones 7 , prepared from (2‐aminophenyl)(2‐halophenyl)methanones 5 by a convenient three‐step sequence, with secondary amines in DMF at room temperature to generate the corresponding thiourea derivatives 8 in situ, which are treated with NaH at 100–120° to provide the desired products in one‐pot reactions in generally good yields.     

Crucial role of linker portion in acridine-bearing oligonucleotides for highly efficient site-selective RNA scission

Through a series of linkers, 9-amino-2-methoxy-6-nitroacridine and 9-amino-6-chloro-2-methoxyacridine were tethered to the middle of oligonucleotide, and the abilities of these conjugates for site-selective activation of RNA (inducing site-selective scission by Lu(III)) were compared. The RNA-activating ability was strongly dependent on the structures of both acridine and linker. By tethering 9-amino-2-methoxy-6-nitroacridine with a rigid and chiral linker, derived from l-threoninol, quite fast site-selective RNA scission was accomplished.     

Synthesis and metal ion complexation of spin labeled 18-crown-6 ethers containing an acridone or an acridine fluorophore unit

Double (spin and fluorescence) labeled pyrroline derivatives of crown ethers containing an acridone or an acridine fluorophore unit (1 and 2) and their diamagnetic analogues (3 and 4) were synthesized. Their fluorescent behavior as well as their complexation properties toward selected metal ions (Na⁺, K⁺, Mg²⁺, Ca²⁺, Zn²⁺) were examined.     

吖啶橙指示荧光分析法测定双酚A

基于在酸性介质中,双酚A对羟自由基与吖啶橙的氧化还原反应的阻抑作用,建立了测定双酚A的荧光分析新方法.该方法简单,快速,线性范围为1.0～100 ng/mL,检出限为0.21 ng/mL.将其用于塑料制品中双酚A的测定,结果满意.     

吖啶黄催化动力学光度法测定纺织品中的微量甲醛

在硫酸介质中,甲醛能灵敏地催化溴酸钾氧化吖啶黄褪色,据此建立了一种测定甲醛的催化动力学光度法.在5.0-150.0μg/L范围内,△A与甲醛的浓度呈良好的线性关系,线性方程为△A=0.0292+0.0084C(μg/L),检出限为0.57μg/L.用于纺织品中甲醛的测定,相对标准偏差小于4.50%,加标回收率为96.6...