Studies on the inclusion complex reaction and fluorescent analytical application of β-cyclodextrin with hymecromone

The inclusion complex reaction condition and the mechanism of β-cyclodextrin with hymecromone have been studied by fluorescent spectrum. The fluorescent intensity and the stability of the system can be qreatly increased in qiven condition, and the formation constant of the inclusion complex reaction has been determined too. The system can be applied to the determination of trace amounts of hymecromone, the maximum fluorescent intensity is obtained with excitation and emission wavelength at 362 nm and 452 nm, respectively. The linear range for hymecromone is 8.0×10⁻⁹ mol·L⁻¹ to 1.0×10⁻⁵ mol·L⁻¹. The detection limit is 1.8×10⁻⁹ mol·L⁻¹. A simple, rapid and highly sensitive fluorimetric method is proposed for the determination of hymecromone. The results obtained are in agreement with those given by an official method. Foundation item: Supported by the National Natural Science Foundation of China (G1999046703) Biography: Luo Zhao-fu(1947-), female, Associate professor.     

固载表面自组装成环荧光显微成像技术测定阿摩尔量羟甲香豆素

实验了在辅助成环剂PVA 124存在下,羟甲香豆素的碱性小液滴在经二氯二甲基硅烷处理的疏水性载玻片上,由于接触线的自固定及接触线附近溶剂的挥发,液滴内部产生向外的毛细流将飞摩尔量羟甲香豆素带到接触线上,富集形成环直径小于1 1mm,环带宽小于26 4μm的SOR.环线上溶质的最大荧光强度和羟甲香豆素的浓度成正比关系,当点样体积为0 1μL时,Imax正比于0 1～80 0飞摩尔量的羟甲香豆素(或0 1～40 0×10-8mol/L),检测限达到13 0阿摩尔(或1 3×10-10mol/L)(S/N=3).用本法实测口服药中羟甲香豆素的含量及实际尿液中的回收率在96 0%～104 3%,相对标准偏差为2 7%～3 8%.     

羟甲香豆素荧光猝灭法测定羟自由基产生量及常见食品水提物羟自由基清除率测定的研究

在pH 10.17 NH3-NH4Cl缓冲介质中,利用Mn2+-H2O2体系产生的羟自由基对羟甲香豆素荧光强度的猝灭,确立了荧光法测定羟自由基产生量的新体系;用抗坏血酸作羟自由基清除剂,测定其清除率,结果表明抗坏血酸对·OH的清除作用具有明显的量效关系;同时用羟甲香豆素荧光猝灭法实测了常见食品桃、橙子、芹菜、茄子等10种新鲜水果和蔬菜水提物对·OH的清除率,其大小顺序为桃>橙子>香蕉>草莓>芹菜>茄子>苹果>西红柿>黄瓜>梨.由此建立了测定羟自由基清除率的新方法.该方法具有较好的稳定性和灵敏度.