Commonly used disinfectants can be categorized into nine main types based on their ingredients: chlorine-containing disinfectants, peroxide disinfectants, aldehyde disinfectants, alcohol disinfectants, iodine-containing disinfectants, phenolic disinfectants, ethylene oxide disinfectants, biguanide disinfectants, and quaternary ammonium salt disinfectants.
Chlorine-containing disinfectants
These are disinfectants that dissolve in water to produce hypochlorous acid, which has antimicrobial activity. Their effective antimicrobial component is often expressed as available chlorine. Hypochlorous acid has a small molecular weight, easily diffuses to the surface of bacteria, and penetrates the cell membrane to enter the bacterial cell, causing bacterial protein oxidation and leading to bacterial death.
Peroxide disinfectants
These have strong oxidizing capabilities, and various microorganisms are highly sensitive to them, capable of killing all microorganisms. These disinfectants include hydrogen peroxide, peracetic acid, chlorine dioxide, and ozone. Their advantage is that they leave no residual toxicity on items after disinfection.
Aldehyde disinfectants
These include formaldehyde and glutaraldehyde. The disinfection principle of this type is that a reactive alkylating agent acts on the amino, carboxyl, hydroxyl, and sulfhydryl groups in microbial proteins, thereby destroying the protein molecules and causing microbial death. Alcohol-based disinfectants
The most commonly used are ethanol and isopropanol. They coagulate proteins, leading to the death of microorganisms. Classified as medium-efficiency disinfectants, they kill vegetative bacteria and destroy most lipophilic viruses, such as herpes simplex virus, hepatitis B virus, and human immunodeficiency virus.
Iodine-containing disinfectants
Including tincture of iodine and povidone-iodine, they kill vegetative bacteria, fungi, and some viruses. They can be used for skin and mucous membrane disinfection and are commonly used in hospitals for surgical hand disinfection.
Phenolic disinfectants
Including phenol, cresol, halogenated phenols, and phenol derivatives. A commonly used phenol soap, also known as Lysol, has methylphenol as its main component. Halogenated phenols can enhance the bactericidal effect of phenol. For example, trichlorohydroxydiphenyl ether is widely used as a preservative in clinical disinfection and preservation.
Ethylene oxide
Also known as ethylene oxide, it is a highly effective disinfectant that can kill all microorganisms. Due to its strong penetrating power, it is often used for disinfection or sterilization of leather, plastics, medical devices, and medical supply packaging. It does not damage most items and can be used for the disinfection of precision instruments and valuables. It has no effect on paper color and is commonly used for the disinfection of books and written documents.
Biguanide and Quaternary Ammonium Salt Disinfectants
In addition, there are biguanide and quaternary ammonium salt disinfectants. These are cationic surfactants with bactericidal and detergency properties. In hospitals, they are generally used for cleaning and disinfecting non-critical items and can also be used for hand disinfection. Dissolving them in ethanol enhances their bactericidal effect, making them suitable as skin disinfectants. Because these compounds can alter the permeability of bacterial cell membranes, they are often combined with other disinfectants to improve their bactericidal effect and speed.
