A hydrogen-peroxide digestion system for tissue trace-metal analysis.

Area of Science:

• Analytical Chemistry
• Environmental Science
• Biochemistry

Background:

• Traditional trace metal analysis requires harsh acid digestion, posing contamination risks and demanding specialized equipment.
• Strong acids like nitric and perchloric acid are commonly used, necessitating extensive glassware cleaning and fume hood precautions.

Purpose of the Study:

• To develop and refine a safer, simpler tissue digestion technique for trace metal analysis.
• To evaluate the efficacy of hydrogen peroxide for digesting various biological tissues for multi-elemental quantification.

Main Methods:

• Utilized a simplified digestion procedure employing 30% and later 50% hydrogen peroxide (H2O2) in polyethylene vials at approximately 75°C.
• Applied the method to liver tissue for the analysis of zinc, selenium, copper, manganese, and arsenic using atomic absorption spectrophotometry.
• Assessed reagent blank readings and recovery rates for added arsenic to validate the method's accuracy.

Main Results:

• Insignificant reagent blank readings were observed, indicating minimal contamination.
• The hydrogen peroxide digestion method demonstrated effective recovery of added arsenic, even at low concentrations.
• The procedure was optimized for reduced digestion time using 50% H2O2.
• The resulting digest is suitable for multi-trace metal analysis.

Conclusions:

• Hydrogen peroxide offers a safer and more convenient alternative to strong acids for tissue digestion in trace metal analysis.
• This optimized method facilitates the accurate and reliable quantification of multiple trace metals in biological samples.
• The technique minimizes environmental contamination risks and simplifies laboratory procedures.