This study investigated the use of chromatography/mass spectrometry for the analyzing amino acids in human hair.
This paper explores the use of trimethylsilyl derivatization gas chromatography/mass spectrometry for the quantitation of amino acids in human hair. The distribution of amino acids in hair can divulge information regarding the health (e.g., diabetes) and provide a means for detecting the history of the disease by segmentation of the hair as well as attributes of an individual (e.g., sex and age). Therefore, an nonenzymatic method of hair digestion and profiling is required. In addition to optimizing and validating a method for measuring the distribution of amino acids in human hair, a robust and comprehensive approach to objectively compare the most effective means of extracting and manipulating chromatographic data to obtain the best limits of detection, linearity, and sensitivity are provided. Data comparisons were made by operating the mass spectrometer in a mode that rapidly switches between total ion current (TIC) and selected ion monitoring (SIM) modes during each sample injection. In this way, any external confounding factors were negated that may otherwise influence the comparison of the linearity and sensitivity between the two modes of operation. The use of SIM, peak areas, and an internal standard provided significantly better sensitivity and limits of detection than using peak heights, TICs, or no internal standard. (Published Abstract Provided)