Analysis of deposits on high water content contact lenses

• DOI: 10.1002/jbm.820170205
• Publication Date: 2004-12-31T12:39:26Z
• Authors: S. Hosaka; H. Ozawa; H. Tanzawa; H. Ishida; K. Yoshimura; T. Momose; H. Magatani; A. Nakajima
• Keywords: 03 medical and health sciences; 0302 clinical medicine; Spectrophotometry, Infrared; Tears; Humans; Muramidase; Amino Acids; Contact Lenses, Hydrophilic; Spectrum Analysis, Raman; Electron Probe Microanalysis

Deposits on soft contact lenses of high water content were investigated morphologically and chemically compared with those conventional poly (2-hydroxyethyl methacrylate). The material the examined in this investigation was crosslinked copolymer methyl methacrylate N-vinylpyrrolidone a higher than 70%. Morphologically, deposits found to have no characteristics distinguishable from lenses. By electron microscopic observation cross section lens that had become opaque, it confirmed deposit surface within lens. Some spots recognized as colonies microorganisms, but majority involvement by microorganisms. Surface analysis Fourier transform infrared spectrometer (FT-IR) main component filmy protein. Protein detected most deposits. amino acid compositions proteins be close lysozyme. From elemental several spots, silicon, aluminum, iron, some other elements detected. structural laser Raman microprobe (MOLE) revealed existence lipids. In cases, grown around defect surface. A mechanism for formation is suggested.