It is the use of physical agents and chemicals to kill or stop the growth of pathogenic microorganisms (viruses, bacteria, fungi, parasites). The agents or uses for this disinfectant are called disinfectants. Unlike antibiotics, which at their highest concentrations are only bacteriostatic and have a lethal effect on bacteria after several hours of contact, disinfectants generally work in less time (within minutes) and bacteria and even some viruses, They also kill fungi and parasites. In addition, disinfectants are commonly used for inanimate surfaces, and many of them are toxic in concentrations used for animals. Certain disinfectants used on the surface of animals and humans are called antiseptics.
An ideal disinfectant should have the following important conditions:
- Cheap and affordable.
- Have a quick effect.
- Has a wide range of effects on bacteria, viruses, fungi, etc.
- Do not develop microorganisms resistant to it.
- Do not inactivate by organic matter.
- Have minimal toxicity.
- It has no destructive effect on the building and equipment and does not leave any color.
- Do not irritate the skin and mucous membranes of animals and humans.
- Be odorless.
- Dissolves well in water (even heavy water) and does not precipitate.
- Have cleansing properties.
- Its permeability to seams and cracks of surfaces is high.
- It has good chemical stability against air, water, temperature, etc.
The effectiveness of each disinfectant depends on many factors including concentration, time, temperature, type of microorganism (including virus, bacteria, fungus, parasite, spores, etc.), the number of microorganisms in the environment and the quality of the environment. The activity of a microbicide depends primarily on the molecular movement of the particles and the disinfection interaction with the target microorganisms. Also, the concentration, temperature, pH and type of disinfectant (carrier) substance in turn affect the molecular movement of particles. As the disinfectant contact time increases, its penetration rate increases and its lethal effect increases. Disinfectants have different abilities depending on the type of microorganism they encounter.