DEVELOPMENT OF A HIGH PRESSURE/TEMPERATURE FOCUSED MICROWAVE HEATED TEFLON BOMB FOR SAMPLE PREPARATION

A new high pressure/temperature TFM-Teflon bomb for analytical sample preparation is described. The novel prototype system uses focused microwaves, operated at 2.45 GHz, to improve digestion capability. Up to 100-W microwave power can be concentrated into a single polymer vessel containing sample and nitric acid. Methodology was developed using powdered biological reference material. The feasibility of using water for in situ vessel cooling was investigated. The residual carbon content of bovine liver sample was determined by coulometry after combustion in an oxygen stream to evaluate the effectiveness of the decomposition procedure. With this new decomposition device, organic material is totally oxidized with nitric acid is a single-step procedure. The sample preparation time is similar to 10 min (including subsequent cooling time and preparation of the final solution).