A simple and inexpensive modification of the injection port and detector configuration of a standard gas chromatograph, equipped with a nitrogen-phosphorus detector, permits the installation of a fused silica capillary column. Different ways of connecting the column to the injector and its impact on the interchangeability of the columns are discussed. The application of the system to toxicological determinations of clinical and forensic interest has been investigated, using a direct injection technique. The method allows the quantitative determination of different alkaloids and drugs in human biological samples in the low nanogram range, with reliable reproducibility and linear response.
- Gas chromatography