The most common methods of sterilization practised in lab are

☛ Dry heat: Specimen containing bacteria is exposed to high temperature

☛ Wet heat: Pressurised steam is used to kill microbes, for example, autoclave that is like pressure cooker that produces steam.

☛ Filtration: Filtration is used where filters are as small as 0.2um is used

☛ Radiation: UV has limited penetration, so it is generally safe to use although it is less effective to X-rays and gamma rays. X-rays and gamma rays are used only for special purposes only

☛ Solvent: Solvent like ethanol and iso-propanol kills microbial cells but not the spores