Alternative Sterilization Methods

Tests run on various water samples containing bacteria indicate that an alternative microwave-pressure cooking method for the sterilization of apparatus and materials may be used in mobile laboratories. In comparison with the “Standard Methods for the Examination of Water and Wastewater” (AWWA/APHA/WEF), the proposed sterilization method and the standard sterilization method produced equivalent results. Phosphate buffer and nutrient media plates were run as controls and throughout the experimentation produced no bacterial growth. Microwaving may be used alone to sterilize glassware and some thermal-proof plastics. The recommended operational conditions are: the highest power setting for 25 minutes. A pressure cooker alone is feasible for the sterilization of phosphate buffer, dilution water, and for the preparation of bacteria-free water, which in turn can be used for preparing nutrient media. The recommended operational conditions are: the pressure cooker’s highest pressure setting for at least 15 minutes at 100°C. The combination of a microwave oven and a pressure cooker can be an ideal substitute for an expensive autoclave, which is used for sterilization in large medical and water quality control laboratories.