Study On The Determination Methods Of Several Local Anesthetics And Lidocaine Metabolites

In this thesis, several sensitive methods were developed for determination of local anesthetics by solid phase extraction (SPE) pretreatment and gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-linear ion trap mass spectrometry (LC-LIT-MS).The content of the research embraces four principal sections:(1) The progress of research on the detection of local anesthetics was reviewed. The characteristics, detection methods, and pretreatment techniques of local anesthetics were summarized. The studying contents and meanings of the thesis were posed.(2) The methods were developed for determination of six local anesthetics (benzocaine, lidocaine, procaine, tetracaine, pramocaine, and dibucaine) in blood by SPE/GC-MS. The conditions of solid phase extraction such as acidity-basicity of solutions,type and amount of elution solvents were optimized. And better results were achieved.(3) The methods were developed for determination of nine local anesthetics (lidocaine, procaine, benzocaine, tetracaine, dibucaine, pramocaine, bupivacaine, ropivacaine, and prilocaine) in blood by online solid phase extraction liquid chromatography linear ion trap mass spectrometry (SPE/LC-LIT-MS). The conditions of online solid phase extraction were optimized, such as extraction time, addition amount of acetonitrile, and acidity-basicity of solution and so on. This established method was simple, rapid, accurate, sensitive and suitable for screening analysis of mutiple local anesthetics in blood.(4) The methods were developed for the identification of lidocaine and its metabolites including GX, MEGX,2,6-xylidine and hydroxylidocaine in rats urine by GC/MS and LC/MS. The metabolites were identified according to the mass spectra. And the proposed metabolic pathways were speculated. These established methods for several local anesthetics were simple, rapid, accurate, sensitive and suitable for screening analysis of multiple local anesthetics in blood, and could provide a reference for the detection of related criminal cases and technical standards for forensic science. The metabolites of lidocaine were researched in rat urine. The technical support for the related cases were provided by the analysis and identification of metabolites, and inference of metabolic pathways of lidocaine.