Presence of free radicals in commonly used ophthalmic preparations
- David Lockington1,
- Elisabeth Macdonald1,
- Marilena Gregory1,
- Philip Stewart2,
- Muriel Caslake2,
- Kanna Ramaesh1
- 1Tennent Institute of Ophthalmology, Glasgow, UK
- 2Division of Cardiovascular and Medical Sciences, Glasgow Royal Infirmary, Glasgow, UK
- Correspondence to Dr David Lockington, Tennent Institute of Ophthalmology, Gartnavel General Hospital, 1053 Great Western Road, Glasgow G12 0YN, UK; davidlockington{at}hotmail.com
- Accepted 7 May 2009
Free radicals can cause direct cellular damage, a role increasingly defined in cardiovascular disease, but less distinct in ophthalmology. Preservatives in topical medications are known to cause toxicity and cytotoxic damage to the corneal surface.1 We set out to evaluate if free radicals were present in commonly used ophthalmic preparations and if they were present in sufficient qualities to contribute to ocular surface instability.
Samples of commonly used ophthalmic preparations were analysed for total free-radical presence by indirect analysis via Total Antioxidant Status (TAS kit, RANDOX Laboratories, Crumlin, UK). They were contrasted with preservative-free Minims preparations. Various solutions including 0.5% hydrogen peroxide were also assessed to provide an appropriate reference result. Fifty-six ophthalmic preparations available in outpatients were sampled, including 18 Minims preparations, seven topical …
