MODERATED PRESSURE MICROWAVE DIGESTION SYSTEM FOR PREPARATION OF BIOLOGICAL SAMPLES

A new type closed digestion vessel was constructed for digestion of bi ological samples. In this the vapour pressure can be maintained on mod erated level (150-300 kPa) by means of an internal cooling spiral. Dur ing the operation the reflux of the condensed acid and water vapour co ntinuously renews the liquid phase over the sample. By this way a less expensive microwave system may be applied. The performance of this in strument is practically equal to the commercial systems. The digestion time of plant and tissue samples is 5-10 min and the analytical resul ts for reference materials are in good agreement with the reference va lues.