Sterilization of ophthalmic drugs and intraocular lenses

Poster presented at the First International Congress of CiiEM - From Basic Sciences to Clinical Research. 27-28 November 2015, Egas Moniz, Caparica, PortugalFundação para a Ciência e a Tecnologia: projects UID/QUI/00100/2013 and M-ERA.NET/0005/201

Effect of sterilization on drugs and lenses for ophthalmic applications

Poster presented at the 10th World Biomaterials Congress. Montreal, Canada, 17-22 May 2016N/

Chitosan/alginate based multilayers to control drug release fromophthalmic lens

In this study we investigated the possibility of using layer-by-layer deposition, based in natural polymers (chitosan and alginate), to control the release of different ophthalmic drugs from three types of lens materials: a silicone-based hydrogel recently proposed by our group as drug releasing soft contact lens (SCL) material and two commercially available materials: CI26Y for intraocular lens (IOLs) and Definitive 50 for SCLs. The optimised coating, consisting in one double layer of (alginate – CaCl2)/(chitosan + glyoxal) topped with a final alginate-CaCl2 layer to avoid chitosan degradation by tear fluid proteins, proved to have excellent features to control the release of the anti-inflammatory, diclofenac, while keeping or improving the physical properties of the lenses. The coating leads to a controlled release of diclofenac from SCL and IOL materials for, at least, one week. Due to its high hydrophilicity (water contact angle ≈ 0) and biocompatibility, it should avoid the use of further surface treatments to enhance the useŕs comfort. However, the barrier effect of this coating is specific for diclofenac, giving evidence to the need of optimizing the chemical composition of the layers in view of the desired drug.info:eu-repo/semantics/publishedVersio

Composite comprising nanoparticles and method of making nanoparticles

publication date: 2012-06-13; filing date: 2011-11-09A method for making nanoparticles of a conjugated polymer, the method having the following steps (i) providing a reaction mixture with a monomer, a photosensitising agent and a solvent, and (ii) exposing the reaction mixture to photo irradiation to form nanoparticles of a conjugated polymer. The composite compring the nanoparticles may be used in an intraocular lens implant

Composite comprising nanoparticles and method of making nanoparticles

publication date: 2012-06-14; filing date: 2011-11-11The invention relates to a method for the production of nanoparticles comprising a conjugated polymer. The method comprises (i) providing a reaction mixture with a monomer, a photosensitising agent and a solvent, and (ii) exposing the reaction mixture to photo-irradiation to form nanoparticles of a conjugated polymer wherein the photosensitising agent is immiscible with the solvent

Biomechanical and optical properties of 2 new hydrophobic platforms for intraocular lenses

Purpose: To compare the biomechanical and optical properties of 2 new hydrophobic platforms and a series of commercially available foldable intraocular lenses (IOLs). Results: With 1 exception, IOLs equilibrated in aqueous medium had a lower glass-transition temperature, higher deformability, lower injection forces, and complete recovery of their initial optical properties after injection. Typical hydrophobic acrylic dry-packaged IOLs required higher injection forces with high residual deformation and lost part of their initial optical quality after injection. Hydrophobic acrylic C-loop, double C-loop, and closed quadripod haptics applied optimum compression forces to the capsular bag with negligible optic axial displacement and tilt compared with plate haptics and poly(methyl methacrylate) haptics. Conclusions: The combination of the C-loop haptic and the bioadhesive glistening-free material, which absorbs a predetermined amount of water, allowed for a biomechanically stable IOL. The same material used in association with a double C-loop haptic design facilitated the perioperative manipulation and placement of the IOL in a smaller capsular bag without impairing the other biomechanical properties of a single C-loop design

Flourinated material

publication date: 2010-11-03; filing date: 2009-04-27This invention relates to a method for modifying the surface of a material for use with a biological sample or tissue comprising the steps of providing a material having a surface which comprises reactive-functional groups; providing fluorinated molecules having reactive-functional groups complimentary to those on the material surface; using wet chemistry to attach the fluorinated molecules to the surface of the material by reacting the reactive-functional groups of the implant with the complementary reactive-functional groups of the fluorinated molecules. The invention also relates to materials modified by said method and to implants made using said materials