Biguanide, or polyhexamethylene biguanide, is a solution or pale yellow to white solid used as a preservative or disinfectant. It is used in a number of applications but is most well-known as an alternative to chlorine for sanitizing pools. Biguanide sanitizer offers several advantages but is not without drawbacks.
Biguanide is a preservative or sanitizer in several applications. As a sanitizer, it is well-known for recreational water treatment but also used for wound irrigation and to disinfect sterile dressings, medical utensils, animal drinking water, farm equipment and surfaces used for handling food. Biguanide is also in antimicrobial hand rubs and washes. Biguanide is a preservative in personal care products, cosmetics, wet wipes, contact lens solutions and others.
Advantages of Biguanide
Biguanide offers several benefits as an alternative to chlorine or bromine pool sanitizers. Biguanide does not require a stabilizer or degrade with changes in pH or high temperature. It does not have the odor that chlorine does, creates a smoother-feeling water and does not irritate skin or eyes if used correctly. Additionally, biguanide is less susceptible to UV rays than the halogen sanitizers, bromine and chlorine, and typically only needs to be applied every few weeks.
Disadvantages of Biguanide
Although biguanide offers several benefits as an alternative to chlorine, there are some drawbacks associated with biguanide-based sanitizers. Biguanide is more expensive than bromine or chlorine sanitizers. It is not compatible with non-chlorine shock, chlorine, bromine or copper-based materials. Finally, biguanide may demonstrate a tendency to gum up filters.
Testing and Adjusting Biguanide Levels
Biguanide levels are tested using special manufactured kits. Regularly, properly performed testing at least every two weeks will ensure that the correct amount and frequency of sanitizer is added to the water. Be sure to check with a pool supply dealer, manufacturer or other expert before adding any supplemental chemicals to pools treated with biguanide, as they may not be compatible.
Additional Alternatives to Chlorine
Biguanide is generally used because it offers an alternative to chlorine. Several additional purification systems also offer alternatives to traditional chlorine. These include metal purification, ozone systems, UV systems and saltwater chlorination.
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- Arch Chemicals; Polyhexamethylene Biguanide (PHMB); Apr. 2008
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