title: Estimation of monomer content in polymethyl methacrylate contact lens materials by Raman spectroscopy.
abstract: Polymethyl methacrylate is the most commonly used contact lens material due to its excellent optical properties. However the presence of residual monomer in the structure alters its transparency as well as its biocompatibility, thus, there is a need to detect any remaining methyl methacrylate. Raman spectroscopy is a rapid, sensitive, and non destructive method as compared to other spectroscopic, chromatographic or polarographic methods. In this study, the spectra of some lens materials (prepared from methyl methacrylate, 2-hydroxy ethyl methacrylate, Hexamethyl disiloxane and polypropylene glycol with or without the addition of crosslinker ethylene glycol dimethylacrylate) were obtained by Raman spectroscopy. It was observed that an amount of crosslinker present in the structure proves effective for the unpolymerized monomer content. None of the samples, except those containing nexamethyl disiloxane, demonstrated any monomer residue.
authors.affiliation: Department of Physics, Faculty of Arts and Sciences, Gazi University, Ankara, Turkey.
authors.forename: Z
authors.initials: Z
authors.lastname: Kantarci
authors.forename: S
authors.initials: S
authors.lastname: Aksoy
authors.forename: N
authors.initials: N
authors.lastname: Hasirci
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D003102:Colloids / Q000032:analysis; D003263:Contact Lenses, Hydrophilic; D003432:Cross-Linking Reagents / Q000032:analysis; D008689:Methacrylates / Q000032:analysis; D020366:Methylmethacrylate; D008768:Methylmethacrylates / Q000032:analysis*; D011108:Polymers / Q000032:analysis; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011409:Propylene Glycols / Q000032:analysis; D013059:Spectrum Analysis, Raman
chemical_list: D001672:Biocompatible Materials; D003102:Colloids; D003432:Cross-Linking Reagents; D008689:Methacrylates; D008768:Methylmethacrylates; D011108:Polymers; D011409:Propylene Glycols; D020366:Methylmethacrylate; C012504:polypropylene glycol; C005044:hydroxyethyl methacrylate; C004919:ethylene dimethacrylate; D019904:Polymethyl Methacrylate