Foldable Antibacterial Acrylic Intraocular Lenses of High Refractive Index

Abstract

Hydrophilic copolymers with high refractive index and bactericide properties based on quaternary ammonium salts monomers and methacrylates bearing benzothiazole moieties have been developed for application as foldable intraocular lenses. Composition of the systems was adjusted to get materials with optimized flexibility, wettability, and refractive properties. All the materials have been characterized in terms of optical properties, glass transition temperature, water content, and wettability. Water contact values oscillated between 37 and 15% and refractive index values in the wet state between 1.49 and 1.53, depending on composition. Glass transition temperature interval was 63-77 degrees C. Values of surface free energy of the solid ranged from 49 to 54 mN/m, characteristic of IOL hydrogel materials. Bactericide properties of the quaternary ammonium salts methacrylates were higher than that of the benzothiazole derivative, showing inhibition halos as high as 23-25 mm in antibiogram tests against S. epidermidis and P. aeruginosa , strains found in the ocular cavity and responsible for most postsurgical endolphthalmitis. Biocompatibility of the systems was evaluated in cell cultures using human fibroblasts. Cellular viability was higher than 90%, and close to 100% in many cases, for the extracts of selected formulations collected at different periods of time.

Broad-Spectrum Antimicrobial Polycarbonate Hydrogels with Fast Degradability

“…16 4, 11, 17, 18 In addition, hydrogels offer a more versatile platform that allows for incorporation of growth factors to accelerate wound healing as compared to traditional gauze dressings. 19,20 The main problem in using hydrogels for wound care is the high risk of infections, as the moist environment of the hydrogels promotes pathogen proliferation and colonization. In order to overcome this issue, antibiotics 13,21,22 or silver 11 were loaded into the hydrogels.…”

Antibacterial Nanopillar Array for an Implantable Intraocular Lens

“…[ 3,11,14,15 ] The antibacterial surfaces such as an antibiotic‐releasing coating, [ 10,13,16 ] coatings based on peptides, and quaternary ammonium compounds have been implemented. [ 17,18 ] Although these antibacterial surfaces have sufficient antibacterial efficiencies, chemical modification methods still have challenges that need to be addressed. These challenges include the cytotoxicity of surrounding cells and the insufficient long‐term stability of polymer coatings.…”

Drug-Eluting Intraocular Lenses

“…Vision loss due to cataracts has represented an important concern along the human history and is far from diminishing; its incidence is rising as life expectancy and prominence of adverse agents (UV irradiation, smoke) or conditions (diabetes, malnutrition) increase [1,2,3,4]. The cataract term refers to the opacification of the crystalline lens or the anterior or posterior part of the lens capsule.…”

“…Treatment of endophthalmitis usually requires intraocular injections and, if failure occurs, the removal of the infected IOL. Therefore, prophylactic strategies such as incorporation of antimicrobial polymers [4] and/or sustained release of antimicrobial agents from the IOLs themselves are gaining increasing attention [22,23,24,25]. The information currently available about IOL/drug combination products is analyzed in the next section.…”