Biomedical Application of Gas Chromatography-Mass Spectrometry

I. INTRODUCTION

During the past decade, integrated gas chromatography-mass spectrometry (GCMS) has become recognized as one of the most versatile and powerful tools in analytical chemistry. The ultimate strength of this technique resides with the unique capability to separate and simultaneously identify the individual components of even the most complex mixture. Sufficient sample volatility is a prerequisite of a successful GCMS analysis. Although this is a serious limitation of the method, GCMS does span an impressive volatility range. An effective identification and a reliable quantitation of a trace component within a complex mixture is largely dependent on the capability of separation. Highly efficient and inert capillary columns and direct sample injectors for these columns are now commercially available, and these have improved sensitivity and reproducibility due to narrower peak profiles and reduced column bleed. Alternatively, short capillary columns can serve extremely well in applications where lesser number of plates are sufficient or where the separation of higher boiling components is desired. A review of the current "state of the art" shows that significant progress continues to be made each year and that many of the new applications of the technique originate from improved instrumentation. The instrumental innovations include: positive and negative ion chemical ionization sources, interfaces for high-resolution glass columns, automated data handling and library searching facilities, and multiple ion detection capabilities.