以鸡肝酯酶催化α-乙酸萘酯发生的水解反应为研究对象,采用MicroDSCⅢ微量热计作为酶催化反应热的测定工具,分析人员操作误差、体积计量器具误差及酶活测定方法误差等对热测量结果的影响。根据各因素引入的误差分析比较,发现上述因素并不是导致试验结果误差的主要因素;经进一步分析,通过控制试验开始前DSC基线稳定时间的一致性可以获得较稳定的反应焓变;通过控制上述因素,测热结果的相对标准偏差由24.32%降至11.85%,并在此基础上测得α-乙酸萘酯的水解反应热为35.54kJ/mol。
The enthalpy of α-naphthyl acetate hydrolysis was meas ured with Micro DSCⅢ and the measurement errors were analyzed in the paper. By comparing the uncertainty derived from operation, measure implement and method of measuring enzyme activity, it could he deduced that the factors were not major reasons for the un certain results. However, the influence of the stabilizing time of base line before enthalpy measurement on the uncertainty was more obvious. By controlling all the factors above, the RSD(relative standard deviation) of the results could reduce from 24.32% to 11.85% and the enthalpy of catalysis witb chicken liver esterase was determined as 35.54 kJ/mol.