Chemical isotope labeling-assisted liquid chromatography-mass spectrometry enables sensitive and accurate determination of dipeptides and tripeptides in complex biological samples  

作　　者：Feng-Qing Huang Yu Wang Ji-Wen Wang Dai Yang Shi-Lei Wang Yuan-Ming Fan Raphael N.Alolga Lian-Wen Qi 

机构地区：[1]State Key Laboratory of Natural Medicines,School of Traditional Chinese Pharmacy,China Pharmaceutical University,Nanjing 211198,China [2]Clinical Metabolomics Center,China Pharmaceutical University,Nanjing 211198,China [3]Department of General Surgery,Zhongshan Hospital,Fudan University,Shanghai 200032,China [4]College of Chinese Materia Medica and Food Engineering,Shanxi University of Chinese Medicine,Jinzhong 030619,China

出　　处：《Chinese Chemical Letters》2024年第11期284-289,共6页中国化学快报（英文版）

基　　金：financially supported in part by the National Natural Science Fund of China for Distinguished Young Scholars(No.81825023);National Natural Science Foundation of China(No.82003979);Natural Science Foundation of Shanghai(No.23ZR1459100)。

摘　　要：Small peptides have attracted increasing attention for their unique features and diverse biological functions.Achieving rapid separation and accurate quantification,however,remains a challenge because of their low abundance and the co-existence of numerous structural isomers.In this study,we developed a novel approach using isotope chemical labeling for ultrasensitive determination of di/tripeptides in biological samples.We successfully synthesized a novel derivatization reagent,4-(2-(ethoxymethylene)-3-oxobutanamido)-N,N,N-trimethylbenzenaminium iodide(EOTMBA)as well as its deuterium-labeled isotope reagent(d_(3)-EOTMBA).A total of 97 small peptides,including 89 dipeptides and 8 tripeptides,could be completely derivatized in methanol within 1.5h at 60℃.After EOTMBA labeling,analysis of these di/tripeptides were achieved within 22 min by LC-MS/MS analysis.The method demonstrated 86.3%-113%accuracy and the limit of quantification ranged from 0.25 fmol/L to 5 nmol/L.Using this method,we achieved ultrasensitive and accurate quantification of di/tripeptides in 147 plasma,49 urine and 46 bile samples obtained from healthy individuals and patients with biliary tract diseases.The identified differential di/tripeptide biomarker panels showed promising diagnostic performance for patients with biliary tract cancer with area under the receiver operating curve values from 0.870 to 0.996.Furthermore,this method was successfully applied to quantify di/tripeptides in the extract of an animal-derived traditional Chinese medicine,Eupolyphaga sinensis Walker.These findings highlight the possible application of the analytical method in clinics and for the purposes of quality control of traditional Chinese medicines.

关 键 词：Di/tripeptides Chemical derivatization Isotope labeling Liquid chromatography tandem mass SPECTROMETRY Biliary tract cancer 

分 类 号：Q503[生物学—生物化学] O657.63[理学—分析化学]