Enzymatic-spectrophotometric determination of paraquat in urine samples: A method based on its toxic mechanism
Enzymatic-spectrophotometric determination of paraquat in urine samples: A method based on its toxic mechanism
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DOI：
10.3109/15376516.2010.490968
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发表时间：
2010-09-01
影响因子：
3.2
通讯作者：
Yonamine, Mauricio
中科院分区：
文献类型：
--
作者：
de Almeida, Rafael Menck;Yonamine, Mauricio
百草枯是一种广谱接触性除草剂，在世界各地的几起意外、杀人性和自杀性中毒中都曾遇到过。该化合物的肺毒性与肺泡细胞中NADPH的耗竭有关，在O2(氧化还原循环)的存在下，NADPH被百草枯和还原酶系统的还原/氧化持续消耗。基于这一机理，建立了测定尿样中百草枯的酶促分光光度分析方法。检测波长为340 nm，每10个S检测一次，检测15min。NADPH的氧化速度与样品中发现的百草枯水平相关。酶促分光光度法灵敏度高，可用于检测尿样中浓度低至0.05 mg/L的百草枯。
Paraquat is a broad-spectrum contact herbicide that has been encountered worldwide in several cases of accidental, homicidal, and suicidal poisonings. The pulmonary toxicity of this compound is related to the depletion of NADPH in the pneumocytes, which is continuously consumed by the reduction/oxidation of paraquat and reductase enzyme systems in the presence of O-2 (redox cycling). Based on this mechanism, an enzymatic-spectrophotometric method was developed for the determination of paraquat in urine samples. The velocity of NADPH consumption was monitored at 340 nm, every 10 s during 15 min. The velocity of NADPH oxidation correlated with the paraquat levels found in samples. The enzymatic-spectrophotometric method showed to be sensitive, making possible the detection of paraquat in urine samples at concentrations as low as 0.05 mg/L.