【摘要】 介绍了吡罗红为指示剂通过荧光降低法研究青蒿素与氯化血红素之间的相互作用。实验发现两者为酶和底物作用模型,作用位点为药物的过氧基团和氯化血红素活性中心的金属离子,其动力学催化常数Km,Vmax和Kcat分别为8.4×10-5mol.L-1,7.4×10-6mol.L-1.s-1及50.23s-1,催化活性分别受去激活剂和高温影响。在最佳条件下,荧光降低值ΔF(F0-F)与青蒿素浓度在0.0~1.27×10-6mol.L-1范围内成线性关系,检测限为2.3×10-8mol.L-1,该方法已用于测定血浆和尿液介质中的微量青蒿素。更多还原

【Abstract】 Hemin-catalytic decomposition of artemisinin （qinghaosu, QHS） was studied using pyronine B （PB） as an indicator. The interaction between hemin and QHS was an enzyme-substrate model, and the action sites were the endoperoxide moiety of QHS and the central metal ion of enzyme respectively. The kinetic catalytic constant depends upon enzyme and substrate concentrations, and the Michaelis-Menten parameters K_m, V max and K cat was 8.4×10 -5 mol·L -1 , 7.4×10 -6 mol·L -1 s -1 and 50.23 s -1 respectively. The catalytic activity of hemin was inhibited in the presence of deactivated agents and at high temperature. Under optimal conditions, the change in fluorescence intensity （F₀-F） of pyronine B was proportional to the QHS concentration from 0.0 to 1.27×10 -6 mol·L -1 , and the detection limit （3σ） was as low as 2.3×10 -8 mol·L -1 . The proposed method was applied to detect the concentration of QHS in the media of plasma and urine.更多还原