Barbiturate analysis in tissue by enzymic digestion and high-performance liquid chromatography

The relative efficiencies of four enzymic digestion procedures and two conventional methods in releasing barbiturates from spiked liver tissue have been compared. The recoveries of these acidic drugs obtained by using papain and neutrase (neutral proteinase from Bacillus subtilis) digestion methods reported now for the first time are higher than those by other enzymatic and conventional methods. These observations are similar to our earlier data on the applicability of these two enzymes to the release of some basic drugs from tissue. Papain digestion gives the maximum recovery of drugs as monitored by HPLC and is the method of choice. The enzymic digestion procedures are relatively simple, inexpensive and yield reproducible results. Analytical procedures for use in routine forensic toxicological analysis are presented.