What type of sterilization uses high-energy rays?

The use of high-energy rays for sterilization is known as ionizing radiation. This method employs gamma rays, X-rays, or electron beams to eliminate microorganisms, including bacteria, viruses, and fungi, by damaging their DNA. The high energy of the rays penetrates materials and disrupts cellular structures, making it an effective means of sterilizing medical devices, pharmaceuticals, and some food items.

Ionizing radiation is particularly advantageous because it can sterilize items without heating them, which is crucial for sensitive electronics and pharmaceuticals that might be adversely affected by heat. This method of sterilization also fosters a longer shelf-life for certain products since it can be performed without the use of chemicals or heat that could alter the substance's integrity or effectiveness.

In contrast, the other sterilization methods listed—dry heat, liquid chemicals, and microwave sterilization—employ different principles. Dry heat sterilization utilizes high temperatures over a prolonged period to achieve sterilization, while liquid chemicals involve the use of potent disinfectants. Microwave sterilization often raises the temperature rapidly but does not penetrate materials as effectively as ionizing radiation in certain applications. Each of these methods has its own specific contexts and limitations, which differentiates them from the unique benefits offered by ionizing radiation.