Adherence of Pseudomonas aeruginosa onto surfactant-laden contact lenses

Abstract

There is an immense research interest to utilise contact lens (CLs) as a popular platform for ocular drug delivery. However, CLs are the major predisposing factors of bacterial keratitis which is commonly caused by adhesion of microbes such as Pseudomonas aeruginosa and Staphylococcus epidermidis. The aim of the current study is to explore the effect of surfactants; Poloxamer 188, Polysorbate 80 and Tetronic 90R4 (at 0.25% - 3% v/v) on the characteristics of CLs and on the adhesion abilities of Pseudomonas aeruginosa to the lenses' surfaces. CLs were formulated using a hydrophilic monomer; 2-hydroxyethyl methacrylate (HEMA) together with silicone-based polymer such as Poly dimethyl siloxane (PDMS) or 3,3,3-trifluoropropylsilane (FSA) then lenses were polymerized under UV light. The formulated CLs with surfactants were found to have an increased equilibrium water content (EWC) due to hydrophilic moiety present in surfactants. A relationship was deduced between EWC and surface contact angle of lenses containing surfactants; where an increased EWC was associated with a decrease in contact angle reflecting a more hydrophilic surfaces of CLs. Apart from the 3% Polysorbate 80 (p < .0001) CLs, all other formulations had light transmission values over 80%. Lenses with surfactants were found to have lower bacterial ATP concentration than lenses without surfactants. Poloxamer 188 in FSA lenses reduced bacterial adhesion from 4.22 × 10 ± 1.30 × 10 pM to 1.03 × 10 ± 4.86 × 10 pM, a reduction by 75.59% when compared to the control lenses (p = .002). Moreover, 1% Tetronic 90R4 in PDMS showed a reduction by 57.17% in ATP concentration. Polysorbate 80 in FSA exhibited the least bacterial adhesion with an average bacterial ATP concentration of 3.85 × 10 ± 2.61 × 10 pM; i.e 90.88% less bacterial ATP than control lenses (p = .001). Bioluminescence studies demonstrated a decrease in Pseudomonas aeruginosa adhesion to CLs containing surfactants without impairing the optical and mechanical characteristics of the lenses.

Patients’ and prescribers’ perception of contact lenses as a potential ocular drug delivery system

“…It has been pointed out that poor hand hygiene (11%), inadequate cleaning of lenses (13%) and lens storage cases (61%) were the main contributors to non-compliance (19). This evidence would indicate that patients may have problems associated with lenses due to inadequate cleaning and hygiene, which put them at possible risk of getting infections (20) that could damage their eye as stated in the current survey. With proper education on lens application and removal, majority of these complications could be avoided.…”

Influence of Selected Surfactants on Physicochemical Properties of Calcium Phosphate Bone Cements

“…The aim of this study was to determine the effect of three nonionic surfactants: Tween 20, Tween 80, and Tetronic 90R4 on the physicochemical properties (phase composition, setting times, porosity, microstructure, bioactivity in vitro) of calcium phosphate bone cements. The studied surfactants according to literature data possess also antibacterial activity which, due to the lack of thermal treatment in CPCs, may additionally allow one to enrich them with these properties. − …”

Contact Lens Technology: From Fundamentals to Applications

“…It has been demonstrated that both P. Aeruginosa and S. Aureus adhere more to ionic hydrogel lenses . An inversely proportional dependence has been observed between bacterial adhesion and water content of the surface . Surfactant‐laden contact lenses have a higher EWC and a lower hydrophobicity which results in less bacterial attachment .…”

“…An inversely proportional dependence has been observed between bacterial adhesion and water content of the surface . Surfactant‐laden contact lenses have a higher EWC and a lower hydrophobicity which results in less bacterial attachment . A higher surface roughness has shown to favor adhesion, and contact lens wear has shown to induce surface roughness due to attachment of tear compounds.…”

“…A higher surface roughness has shown to favor adhesion, and contact lens wear has shown to induce surface roughness due to attachment of tear compounds. In particular, mucin, IgA, BSA, lysozyme and lactoferrin absorption enhance P. Aeruginosa adhesion . Studies reported the ability of multiple bacteria genera to form biofilms on silicone hydrogel contact lenses in presence of dying neutrophils, which can be blocked using specific contact lens solutions .…”