Glutaraldehyde

Glutaraldehyde is a liquid chemical with many advantages like a disinfectant preservative and fixing agent. It is an efficient agent for a range of microorganisms including spores. Glutaraldehyde is a chemical that belongs to the dialdehyde group that has reached wide application as an advanced disinfection agent and sterilant chemical.

Physical and chemical properties

In the table below some of the chemical and physical properties of this product are mentioned. all data that is mentioned in this table is gathered from Wikipedia website:

Glutaraldehyde aqueous solutions

its  Aqueous solutions are acidic. Only when the solution is “activated” (made alkaline) by applying of alkali agents to the pH of 7.5 to 8.5 the solution become the one that has disinfectant properties. (Glutaraldehyde is widely applied in an aqueous solution in concentration from 50 percent to less than 1 percent) The activated glutaraldehyde’s shelf life is just 14 days because in alkaline condition the polymerization of this material occurs. The active part of the molecule that is aldehyde that is responsible for biocidal properties of the whole solution may be deactivated by this polymerization.  To reduce the deactivation process of active sites of this component for its disinfectant properties the mixture of glutaraldehyde-phenol-sodium phenate, potentiated acid glutaric acid dialdehyde, stabilized alkaline glutaraldehyde were found.  It increases the shelf life of the solution for up to 30 days.  Some of the other parameters that the activity is depending on are solution conditions such as concentration and organic matters. One of the main applications of glutaric acid dialdehyde is in health care services because of its biocidal properties. Same as formaldehyde, the disinfectant property of glutaraldehyde has resulted from its alkylation of sulfhydryl, hydroxyl, and carboxyl.

Glutaraldehyde Applications

it is generally applied as a disinfection agent, although it is a toxic chemical and it remains dangerous effect the precautions may not be considered well. And also is applied generally as an advanced disinfectant for medical equipment Like endoscopes and so many other equipment.  This material is noncorrosive for metal equipment and also it does not harm plastics, rubbers and also lenses.

Glutaraldehyde  As a crosslinking agent

Because of its effective crosslinking process with proteins, it is grouped as a specific chemical in this field. Based on this factor it can present in 13 different forms but depending on conditions like ph, solution concentration, temperature and etc.

The Summary of the available forms of this material  in solution is showed in picture below:

Other Applications

• As a biocide for hazardous microbes that are found in oilfields, cooling towers, and pulp and paper industries.
• Fixing agent in the leather tanning industry

Advantageous and disadvantageous

Good points:

• It is grouped as cost-efficient chemicals for the disinfection properties
• Compatible with a wide variety ranges of materials

Bad points:

• Its vapors may cause Respiratory inflammation
• Respiratory irritation from the  vapor
• It may cause coagulation of blood
• May cause allergic reactions

For prevention of the bad points monitoring and control of vapors is essential.

Glutaraldehyde toxicity

Wastewater disposal of hospitals, cooling waters, leather factories, and many other industries may cause the occurrence of this material in water.  But the main source of this chemical which causes water pollution by this chemical is hospital wastes that include disinfectant solutions. Aquatic pollution cause by Glutaraldehyde is because of its quick degradation under both aerobic and anaerobic circumstances in water and under aerobic conditions in the soil. It is considered to be rather mobile in soils. this chemical does not bioaccumulate in aquatic organisms. Because of its formulation that is consist of some ionic and nonionic surfactants, it is considered as toxic material to small planktonic crustaceans in seawater. And as mentioned before in alkaline solution the risk of polymerization is higher than other solutions so the acidic and neutral solution is more compatible with this chemical.

References

• https://www.future-science.com/doi/10.2144/04375RV01
• https://www.sciencedirect.com/topics/engineering/
• https://www.sciencedirect.com/topics/medicine-and-dentistryglutaraldehyde
• https://www.atsdr.cdc.gov/toxprofiles/tp208-c6.pdf
• http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_0926/0901b80380926256.pdf?filepath=microbial/pdfs/noreg/253-03378.doc&fromPage=GetDoc
• https://en.wikipedia.org/wiki/