摘要
在细胞色素C催化下，吡啰红B与青蒿素反应导致荧光降低，细胞色素C与青蒿素的反应为酶-底物模型。动力学研究表明，稳态催化速率依赖于酶和底物浓度，催化常数km、kmax及Kcat．分别为3．3×10^-5mol／L，5．4×10^-6mol·L^-1·s^-1和13．5s^-1，催化活性受去活化剂和乙醇抑制。在pH5．3、25℃及7．6×10^-7mol／L的细胞色素C催化条件下，荧光降低值△F（F0-F）与青蒿素浓度在7．1×10^-8～1．1×10^-6mol／L范围内呈线性关系；检出限为7．2×10^-9mol／L；加标回收率为96．3％～106．8％。方法已用于测定血浆和尿液介质中的微量青蒿素。
A method for the cytochrome C-catalyzed fluorescence determination of artemisinin was developed using pyronine B （PB） as substrate. The interaction between cytochrome C and artemisinin was an enzymesuhstrate model. The kinetic studies demonstrated that the steady-state catalytic rate depended upon enzyme and substrate concentrations, and the Michaelis-Menten parameters, Km, Vmax and Kcat were 3.3 × 10^-5 mol/L, 5.4 × 10^-6 mol · L^-1 · s^-1 and 13.5 s^-1, respectively. Catalytic activity of cytochrome C was inhibited in the presence of deactivated agents CN^- and ethanol. Under optimal conditions （ pH 5.3, 25℃ and 7.6 ×10^-7 mol/L of cytochrome C）, fluorescence intensity change （F0 - F） of pyronine B was proportional to the artemisinin concentration from 7.1 × 10^-8 to 1.1 × 10^-6 mol/L, the detection limit （3σ） was 7.2 × 10^-9mol/L and recoveries are 96.3% - 106.8%. The proposed method was applied to detect the concentration of artemisinin in the media of plasma and urine.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2006年第2期173-177,共5页
Chinese Journal of Analytical Chemistry
基金
国家自然科学基金(No.20075012)
湖南省教委自然科学基金(No.02C313)资助项目
关键词
细胞色素C
青蒿素
吡啰红B
荧光降低值
Cytochrome C, artemisinin, pyronine B, fluorescence intensity change
