Development of an antibody-free method using LC-MS to quantify peptide drugs in human biological fluids

Code: 21A08HK

Administration of some peptide hormones for the purpose to improve physical abilities is prohibited. We have investigated antibody-free analytical methods using PAC-LC-MS to quantify their endogenous concentrations of peptide hormones, particularly growth hormones in the plasma. The latest method enables quantification of endogenous growth hormone (major variant) in human plasma and detection of 11 peptide hormones. Our objectives are to improve the sensitivity of this method to quantify both major and minor variants of endogenous growth hormones in human plasma by improving selectivity for the peptides, and to apply our analytical methods to quantify other peptide hormones in the plasma. We will optimize ion mobility to find the best parameters to separate the target peptides from contaminants. We will also expand our PAC-LC-MS/MS methods to quantify various prohibited peptide drugs, including GHRH and CG, by optimizing the pretreatment process, chromatographic conditions, and MS/MS detection. Human plasma specimens will be collected from healthy subjects who receive growth hormone to monitor the ratio of major variant of GH to minor variant, and the plasma concentration-time profiles of the other peptide hormones with or without GH administration.