A sudden increase in serum creatinine after paraquat intoxication has been reported in several clinical studies. However, this dramatic change of creatinine may be possibly due to an interconversion of creatine-creatinine in relation to paraquat toxicity. In order to investigate the creatine-creatinine relationship, a liquid chromatography tandem mass spectrometry in combination with electrospray ionization was developed and validated for simultaneous determination of creatine and creatinine in the serum. The chromatographic separation was achieved on a Gemini® C6-Phenyl column with a gradient elution consisting of 0.1% formic acid in ultrapure water and methanol as the mobile phase. The method yielded suitable levels of specificity and selectivity, and calibration curves of creatine and creatinine in serum were linear over the concentration range of 0.5-200 µg mL-1. The limit of quantification of both compounds was 0.5 µg mL-1, and the method was accurate within the recovery range of 96.23-102.75%, indicating the robustness of the method. The method was successfully applied to toxicological samples from paraquat-intoxicated patients, and the concentrations of creatine and creatinine were quantified. High creatine concentrations in serum samples were observed which may lead to high serum creatinine despite normal kidney function as creatine is converted to creatinine in proportion to its concentration.

中文翻译：

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百草枯中毒患者中肌酸和肌酐分析的LC-MS / MS方法。

百草枯中毒后血清肌酐突然增加，已有多项临床研究报道。然而，肌酐的这种戏剧性变化可能是由于与百草枯毒性有关的肌酐-肌酐的相互转化。为了研究肌酸与肌酐的关系，开发了一种液相色谱串联质谱与电喷雾电离相结合的方法，并验证了该方法可同时测定血清中的肌酸和肌酐。色谱分离是在Gemini®C6-Phenyl色谱柱上进行的，梯度洗脱由0.1％甲酸的超纯水和甲醇作为流动相。该方法产生了适当水平的特异性和选择性，在0.5-200 µg mL-1的浓度范围内，血清中的肌酸和肌酐的校正曲线是线性的。两种化合物的定量限均为0.5 µg mL-1，该方法在96.23-102.75％的回收率范围内是准确的，表明该方法的耐用性。该方法已成功应用于百草枯中毒患者的毒理学样品，并定量了肌酸和肌酸酐的浓度。尽管肾功能正常，但观察到血清样品中的肌酸浓度较高，这可能导致血清肌酐较高，因为肌酸与其浓度成比例地转化为肌酸酐。指示该方法的鲁棒性。该方法已成功应用于百草枯中毒患者的毒理学样品，并定量了肌酸和肌酸酐的浓度。尽管肾功能正常，但观察到血清样品中的肌酸浓度较高，这可能导致血清肌酐较高，因为肌酸会按其浓度成比例地转化为肌酸酐。表明该方法的鲁棒性。该方法已成功应用于百草枯中毒患者的毒理学样品，并定量了肌酸和肌酸酐的浓度。尽管肾功能正常，但观察到血清样品中的肌酸浓度较高，这可能导致血清肌酐较高，因为肌酸与其浓度成比例地转化为肌酸酐。