Ex vivo evaluation of the stability, safety and antibacterial efficacy of an extemporaneous povidone‐iodine preparation for ophthalmic applications

Abstract

Background: Povidone-iodine is used as a cost-effective broad-spectrum antiseptic in the prophylaxis and treatment of certain ocular infections. In this study, the stability, ophthalmic irritation potential and antibacterial efficacy of an extemporaneous povidone-iodine preparation was determined using established ex vivo and in vitro assays. Methods: Extemporaneous iodine was prepared by simple dilution in normal saline. Preparation stability was evaluated by monitoring concentration and pH. Ocular safety was determined using the bovine cornea opacity and permeability assay. Efficacy was assessed by determining the minimum inhibitory and minimum bactericidal concentration of the preparation on Staphylococcus aureus and Pseudomonas aeruginosa. Results: Diluted povidone-iodine maintained its stability over the 28-day evaluation. The formulation caused mild ocular irritation at the lowest prepared concentration (0.5 per cent w/v), with irritation noticeably increased at higher concentrations. The preparation showed minimum bactericidal and inhibitory concentrations of 0.078 and 0.3 per cent w/v on S. aureus and P. aeruginosa, respectively. Conclusions: This study confirms the stability and broad-spectrum antibacterial efficacy of povidone-iodine, while addressing the ocular irritation potential of this chemical.

Pickering emulsions stabilised with oligoglycine-functionalised nanodiamond as a model system for ocular drug delivery applications

“…63 A 0.1 M NaOH solution was used as a positive control because this base is known to be corrosive to corneal tissue at high concentrations. 64 PBS buffer (pH 7.4) and a conventional emulsion made using Tween 20 (1 mg mL −1 ) were both negative controls. Tween 20 is a surfactant that has been commonly used in ocular formulations.…”

Povidone Iodine 0.66% to Fight <b><i>Pseudomonas aeruginosa</i></b> in Contact Lens Wearer: A Case Report

“…It is not active against several Enterobacteriaceae, P. aeruginosa, all Actinobacteria, and all spores [16]. On the contrary, PVP-I activity, especially at low concentration, against Gram-negative bacteria, including P. aeruginosa, has been clearly demonstrated in in vitro and ex vivo studies [19][20][21]. Low-dose PVP-I has been shown to eradicate also robust biofilms of multidrug-resistant S. aureus, K. pneumoniae, P. aeruginosa, and Candida albicans in vitro [22].…”