title: Impregnation of an intraocular lens for ophthalmic drug delivery.
abstract: In this work the possibility of impregnating P(MMA-EHA-EGDMA) with flurbiprofen using a clean and environmentally friendly technology, namely supercritical fluid technology was evaluated. P(MMA-EHA-EGDMA) has been proposed as a promising matrix to be used for intraocular delivery of anti-inflammatory drugs used in eye surgery and flurbiprofen is a non-steroidal anti-inflammatory agent. Fundamental studies like, the solubility of the drug in carbon dioxide, as well as the sorption degree of this polymeric matrix in the presence of carbon dioxide have been previously carried out. The aim of this research was to evaluate the effects of these two variables in the impregnation process. Different experimental conditions were tested and the results obtained suggest that the best impregnating conditions for this system are low temperatures and pressures, which at the same time correspond to a lower solubility of the drug in the supercritical fluid and a low swelling of the polymeric matrix. Experiments performed also indicate that the batch impregnation process leads to higher yields of impregnation and according to the release profiles obtained the drug can be released from the matrix up to three months, which presents great advantages for post-surgical treatments.
authors.affiliation: Nutraceuticals and Delivery Laboratory, ITQB/IBET, Oeiras, Portugal. rduarte@itqb.unl.pt
authors.forename: Ana Rita C
authors.initials: AR
authors.lastname: Duarte
authors.forename: Ana Luisa
authors.initials: AL
authors.lastname: Simplicio
authors.forename: Arlette
authors.initials: A
authors.lastname: Vega-González
authors.forename: Pascale
authors.initials: P
authors.lastname: Subra-Paternault
authors.forename: Patrícia
authors.initials: P
authors.lastname: Coimbra
authors.forename: M H
authors.initials: MH
authors.lastname: Gil
authors.forename: Herminio C
authors.initials: HC
authors.lastname: de Sousa
authors.forename: Catarina M M
authors.initials: CM
authors.lastname: Duarte
mesh_terms: D000179:Acrylates / Q000737:chemistry; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D001672:Biocompatible Materials / Q000737:chemistry; D002245:Carbon Dioxide / Q000737:chemistry; D003692:Delayed-Action Preparations; D005480:Flurbiprofen / Q000008:administration & dosage*; D006801:Humans; D019654:Lens Implantation, Intraocular / Q000379:methods*; D008689:Methacrylates / Q000737:chemistry; D020366:Methylmethacrylate / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011312:Pressure; D012995:Solubility; D013678:Technology, Pharmaceutical / Q000379:methods; D013696:Temperature
chemical_list: D000179:Acrylates; D000894:Anti-Inflammatory Agents, Non-Steroidal; D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D008689:Methacrylates; D011108:Polymers; D002245:Carbon Dioxide; D020366:Methylmethacrylate; D005480:Flurbiprofen; C004919:ethylene dimethacrylate; C036758:2-ethylhexyl acrylate