Biocide Uptake in Contact Lenses and Loss of Fungicidal Activity During Storage of Contact LensesRosenthal, Ruth A. M.S; Dassanayake, Nissanke L. Ph.D; Schlitzer, Ronald L. Ph.D; Schlech, Barry A. Ph.D; Meadows, David L. Ph.D; Stone, Ralph P. Ph.DEye & Contact Lens: Science & Clinical Practice: December 2006 - Volume 32 - Issue 6 - pp 262-266 doi: 10.1097/ICL.0b013e31802b413f Articles Abstract Author Information Purpose. With recent outbreaks of Fusarium keratitis related to contact lens wear, studies were conducted to determine the biocide uptake during lens storage, and the resulting effect on antifungal activity of related products. Methods. ACUVUE 2 (etafilcon A) soft, hydrophilic contact lenses (group IV) were soaked from 1 hour to 7 days in OPTI-FREE Express and OPTI-FREE RepleniSH multipurpose disinfecting solutions with POLYQUAD (polyquaternium-1) and ALDOX (myristamidopropyl dimethylamine) biocides and multipurpose solutions, Bausch & Lomb ReNu with MoistureLoc (Alexidine), ReNu MultiPlus (polyhexamethylene biguanide [PHMB]), and AMO Complete MoisturePLUS (PHMB). Storage solutions were tested to evaluate the effect of preservative uptake on the residual biocide activity against Fusarium solani. Results. Approximately 30% to 60% of the PHMB and Alexidine were depleted by 6 hours, with comparable loss of antimicrobial activity. Decreasing activity was noted with corresponding decreases in active concentration throughout the course of the evaluation. The POLYQUAD systems retained nearly 100% of the biocide and fungicidal activity and maintained their concentration in the solution. Conclusions. OPTI-FREE Express and OPTI-FREE RepleniSH multipurpose disinfecting solutions maintained fungicidal efficacy after storage of lenses. The Alexidine- and PHMB-based multipurpose solutions tested showed significant uptake of preservative into group IV lenses, resulting in a decrease in the residual activity of the storage solution. The POLYQUAD systems showed a low uptake of biocide and maintained fungicidal efficacy against F. solani. From Alcon Research, Ltd., Fort Worth, TX. The authors are employees of Alcon Research, Ltd. and, therefore, have a financial interest in the subject matter of this article. Dr. Stone is a retired employee of Alcon Research, Ltd. Address correspondence and reprint requests to Ms. R.A. Rosenthal, Alcon Research, Ltd., 6201 South Freeway, Fort Worth, TX 76134; e-mail: firstname.lastname@example.org Accepted October 10, 2006. © 2006 Lippincott Williams & Wilkins, Inc.