abstract |
The invention relates to a photolytic interface and its use in series between a High Pressure Liquid Chromatograph (HPLC) and a chemiluminescence detector for the detection of trace (nanogram) amounts of N-nitroso compounds including N-nitrosamides and non-volatile N-nitrosamines in aqueous-based fluid samples. HPLC effluent containing separated N-nitrosoamino acids and N-nitrosoamino amides is introduced into a glass coil with a purge stream of He and irradiated with ultraviolet light. Nitric oxide cleaved by photolysis is rapidly separated from solvent through a series of cold traps and carried by the He into the reaction chamber of a chemiluminescence detector. Biological matrices, such as urine and gastric fluid, can be analyzed directly at high sensitivity without concentration and/or extraction. |