Abstract
Most conventional digestion procedures, such as dry ashing and wet ashing, are tedious and labor intensive. Microwave digestion is agood alternative, because microwave dissolution is faster, safer, and simpler, and provides more controlled reproducible conditions than conventional methods. The purpose of this study was to develop a microwave digestion method for mineralizing meat and bone meal diets, feces, and ileal contents. Each sample was heated on a hot plate for 10 min, dry ashed at 65°C for 4 h, and transferred into microwave vessels. Then, 10 mL 70% HNO3 was added. Samples were digested for 7,10, and 20 min at 95,90, and 85% power, respectively. After the heating cycle, 6 mL 30% H2O2 was added, and samples were returned to the microwave for a second heating cycle of 1 and 7 min at 95 and 90% power, respectively. Finally, chromium concentration was determined by flame atomic absorption spectrophotometry. The digestion method was validated by using a standard reference material, SRM domestic sludge 2781, with a certified chromium value of 195 ± 9 μg/g. The value obtained in this study was 178 ± 11 μg/g, for a difference of 17 μg/g. Spike recovery experiments resulted in 103.16 and 100.35% recoveries of chromium from diet and feces samples, respectively. Coefficients of variation were 10.8 and 7.8%, respectively.
Trace Element Concentrations in Edible Wild Mushroom Samples From Turkey Determined by Atomic Absorption Methods Using Microwave Digestion vs. Wet Ashing
