Active ingredients in biocidal products – Part I – Alcohols, phenols, aldehydes
Alcohols
Ethanol, isopropanol, and n-propanol are the most widely used alcohols, both as antiseptics and as disinfectants.
They act against bacteria, viruses, and fungi. They inhibit sporulation, but the effect is reversible. They can be combined in low concentrations to enhance the activity of other biocides. Many alcohol-based products also include excipients (including emollients), which decrease the evaporation time of the alcohol, thereby increasing the product's efficacy.
The effect is optimal at concentrations between 60% and 90%.
In 2009, the World Health Organization (WHO) recommended the use of ethyl alcohol-based products for hygienic and surgical hand disinfection by rubbing during patient care to prevent healthcare-associated infections.
Since 2015, the WHO has classified 70% (w/w) ethyl alcohol as an antiseptic and 80% (v/v) ethyl alcohol as a disinfectant.
Isopropyl alcohol is considered slightly more effective against bacteria, while ethyl alcohol is more effective against viruses. At concentrations of 60%-80%, it inactivates all lipophilic viruses (e.g., herpes virus, vaccinia, and influenza virus) and many hydrophilic viruses (e.g., adenovirus, enterovirus, rhinovirus, and rotaviruses, with the exception of hepatitis A virus – HAV or poliovirus). This also depends heavily on the alcohol concentrations as well as the tested microorganism. Isopropyl alcohol has more lipophilic properties than ethyl alcohol, making it less active against hydrophilic viruses (e.g., poliovirus).
Mode of action: denaturation of membrane and cellular proteins.
- Products in the Klintensiv portfolio that contain alcohols include:
- Klintensiv disinfectant gel 85%
- Alchosept
- Dezidiol Spray
- Dezidiol Wipes
- Betaklin
- Klintensiv Sanitary Alcohol 70%
- Klintensiv PVP Iodine Soap
- Klintensiv Hand Disinfectant Wipes 85% Alcohol
- Klinosept
- Klinomed Wipes
- Oxoklin
Phenols
Dr. Joseph Lister was the first surgeon to use phenol as a disinfectant during an operation (1867), with its antimicrobial action being demonstrated in 1881 by R. Koch.
The most commonly used phenol derivatives are ortho-phenylphenol and ortho-benzyl-para-chlorophenol.
They have bactericidal, fungicidal, virucidal, and tuberculocidal efficacy, but are not sporicidal at the recommended use dilution.
They are used for disinfecting hard surfaces (e.g., bedside tables, handrails, and laboratory surfaces) and non-critical medical devices.
Mode of action: in high concentrations, phenol affects the cell wall and precipitates cellular proteins. Low concentrations of phenol inactivate enzyme systems.
- Products in the Klintensiv portfolio that contain phenols include:
- Klinoderm Antimicrobial Soap
Aldehydes
Glutaraldehyde is a saturated dialdehyde used as a high-level disinfectant and chemical sterilant. Aqueous solutions of glutaraldehyde are acidic and thus not sporicidal. When the solution is "activated" using alkalizing agents at pH 7.5-8.5, the solution becomes sporicidal. Once activated, it has a minimum shelf life of 14 days due to the polymerization of glutaraldehyde molecules. Polymerization blocks the active sites of glutaraldehyde molecules responsible for its biocidal activity.
The activated solution has been shown to have a bactericidal effect in < 2 minutes, tuberculocidal, fungicidal, and virucidal in < 10 minutes, and sporicidal (Bacillus and Clostridium) in 3 hours.
Glutaraldehyde is used for disinfecting medical equipment, such as endoscopes, spirometry tubes, dialyzers, transducers, anesthesia and respiratory therapy equipment, hemodialysis proportioning systems, and dialysate delivery systems, and disposable plastic laparoscopic trocars. It is non-corrosive to metal and does not damage lens instruments, rubber, or plastic materials.
The mode of action results from the alkylation of sulfhydryl, hydroxyl, carboxyl, and amino groups of microorganisms, which alters RNA, DNA, and protein synthesis.
- Products in the Klintensiv portfolio that contain aldehydes include:
- Glutanol concentrate
Conclusions
In conclusion, alcohols such as ethanol, isopropanol, and n-propanol, phenols, and aldehydes are widely used as disinfectants and antiseptics in the medical field and in various hygiene applications. These substances act effectively against bacteria, viruses, and fungi, and their proper use is essential for the prevention and control of healthcare-associated infections and other communicable diseases. To ensure the full efficacy of disinfectants, it is important to follow the instructions for use and to select the appropriate products for each specific application.
Bibliography
- https://www.cdc.gov/infectioncontrol/guidelines/disinfection/references.html
- https://www.aefa.es/wp-content/uploads/2014/04/Antiseptics-and-Disinfectants_Activity-action-and-resistance.pdf
- Antiseptic Stewardship. Biocide Resistance and Clinical Implications – Günter Kampf
