Infra-red heating as an alternative technique for fast sample preparation

A procedure for sample preparation was investigated in this work using infr a-red radiation generated by tungsten lamps for fast heating of an acidic s ample suspension contained in a glass flask. The main advantages of the dev eloped procedure are its simplicity and low-cost. Additionally the dilute a cid solution is heated in less than 60 s and the total sample preparation i s performed in less than 5 min. The proposed procedure is suitable for trac e analysis and it can be easily implemented. The preliminary investigations focus on the determination of Cu, Fe, Mn, and Zn in bovine liver and apple leaves as standard reference materials. All results are in agreement at a 95% confidence level. Copper and Mn were also determined in a sample of bov ine liver without any sample pretreatment or after a freeze-drying step for comparison. For this sample, the results were validated using a convention al microwave-assisted closed vessel procedure.