吖啶橙染料在表面活性剂存在时溶液状态的光谱研究

应用紫外－可见吸收光谱和荧光光谱，研究了激光染料吖淀橙（ＡＯ）的溶液状态以及添加表面活性剂时吖啶橙染料的溶液状态变化，并应用Ｋａｓｈａ理论推算出二聚体时的状态，结果表明：在吖啶橙溶液中，ＡＯ二聚体的α＝４９°，ｒ＝１．３９ｎｍ。     

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。     

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.     

Novel DNA bis-intercalators of isoquinolino[4,5-bc]acridines: design, synthesis and evaluation of cytotoxic activity

Mono- and dinuclear isoquinolino[4,5-bc]acridine derivatives were designed and facilely synthesized, their DNA-binding affinities and cytotoxic activities were evaluated. A4 induced unwinding of supercoiled plasmid pBR 322 DNA by (36±2)° while A6 induced that by (41±1)°, both of which were higher than the mono-analogue A1 ((19±2)°). A6 exhibited the highest in vitro antitumor activity against human lung cancer cell (A549) and A4 was the most active one against murine leukemia cell (P388). DNA binding constant and molecular model indicated that both the length of linker chain and the distance of interchromophore were key impact factors for DNA binding affinity and biological activity.     

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。     

动力学荧光法测定柠檬酸的研究

在磷酸介质中 ,柠檬酸对钒 (Ⅴ )催化溴酸钾氧化吖啶橙反应具有活化作用 ,使吖啶橙荧光猝灭 ,据此建立了动力学荧光法测定柠檬酸的新方法。方法的线性范围为 0 .2～ 10 μg·ml- 1,检出限为 0 .0 8μg·ml- 1。将方法直接用于汽水中柠檬酸含量的测定 ,结果满意。     

吖啶橙共振光散射法测定痕量脱氧核糖核酸

研究了三环杂芳香类染料吖啶橙(AO)与DNA作用的共振光散射光谱,在pH11．5～12．5的范围内,加入DNA导致吖啶橙共振光散射增强,在339nm处,存在一共振光散射增强峰,其强度与DNA浓度呈线性关系,据此建立了一种测定DNA的共振光散射新方法?对于ctDNA,方法的线性范围为14．3～1000μg／L,检出限为2．86μg／L,RSD为3．6％;对于fsDNA,方法的线性范围为24．0～1250μg／L,检出限为4．78μg／L,RSD为6．0％。已用于合成样品中DNA的测定。     

Synthetic studies of benzo[b]pyrrolo[4,3,2-de][1,10]phenanthroline

6,11-Dihydrobenzo[b]pyrrolo[4,3,2-de][1,10]phenanthroline-5,8-dione (6), which possesses a unique heterocyclic ring system similar to that in plakinidines A-D (1-4), was synthesized from 2-acetyl-3′-nitrodiphenylamine (16) in nine steps.