PAPB

Polyaminopropyl biguanide (PAPB) is a preservative used in cleaning solutions for contact lenses.

U.S. Pat. No. 4,758,595 to Ogunbiyi et al. discloses a contact-lens solution containing a Polyaminopropyl biguanide (PAPB), also known as polyhexamethylene biguanide (PHMB) or Polyhexanide, in combination with a borate buffer. These disinfecting and preservative solutions are claimed to have a broad spectrum of bactericidal and fungicidal activity at low concentrations coupled with very low toxicity when used with soft-type contact lenses.

Some of the most popular products for disinfecting lenses are multipurpose solutions that can be used to clean, disinfect and wet contact lenses, followed by direct insertion (placement on the eye) without rinsing. Such a solution must be particularly gentle to the eye, because some of the solution will be on the lens when inserted and will come into contact with the eye.