大鼠尸体组织中三甲胺-氮的检测

Detecting the concentration of Trimethylamine-nitrogen in corpse of rat

目的建立检测尸体组织中三甲胺-氮(TMA-N)含量的方法。方法大鼠肌肉组织样本100mg经预处理后,将三甲胺(TMA)抽提于无水甲苯中,与苦味酸作用,形成黄色的苦味酸三甲胺盐,用分光光度计在410nm处检测吸光度,标准曲线法计算TMA-N含量。结果在1～10mg/L范围内,光密度(OD)值与TMA-N浓度呈现良好线性关系(R2=0.9991,P<0.001)。平均日内差2.37%,平均日间差3.2%。加样平均回收率98.4%;大鼠死后即刻至7d,尸体肌肉组织中TMA-N含量由0.115mg/L上升至18.073mg/L,随死后时间延长呈现增加的趋势。结论死后尸体组织中的TMA-N含量可用分光光度法检测。

Objective To build an experimental method for the determination of trimethylamine-nitrogen （TMA-N） in the tissue of corpse. Methods 100mg of muscle of rat corpse was preprocessed before trimethylamine was extracted with anhydro-methylbenzene, then trinitrophenol was added into extracts, and yellow compounds emerged. The optical density （OD） was detected by spectrophotometer at 410nm and the concentration of TMA-N was calculated using the standard curve. Results There was good linear correlation （R^2 = 0. 9991 ,P 〈 0. 001 ） between OD and the concen- tration of TMA-N in the range of 1 - 10mg/L. The average coefficient of variation （CV） of detection differences within day was 2.37% and that among days was 3.2%. The average recovery of sample was 98.4%. With an extension in postmortem interval（PMI） （from immediately after death to 7 days after death）, the concentration of TMA-N in muscles of rats increased from 0.115mg/L to 18. 073mg/L. Conclusion The concentration of TMA-N in corpse tissues can be detected by spectrophotometric method.