Premium
Characterization and quantitation of PVP content in a silicone hydrogel contact lens produced by dual‐phase polymerization processing
Author(s) -
Hoteling Andrew J.,
Nichols William F.,
Harmon Patricia S.,
Conlon Shawn M.,
Nuñez Ivan M.,
Hoff Joseph W.,
Cabarcos Orlando M.,
Steffen Robert B.,
Hook Daniel J.
Publication year - 2018
Publication title -
journal of biomedical materials research part b: applied biomaterials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.665
H-Index - 108
eISSN - 1552-4981
pISSN - 1552-4973
DOI - 10.1002/jbm.b.33904
Subject(s) - chromatography , mass spectrometry , gel permeation chromatography , wetting , fourier transform infrared spectroscopy , polymer , silicone , differential scanning calorimetry , chemistry , contact angle , analytical chemistry (journal) , polymerization , materials science , chemical engineering , organic chemistry , physics , engineering , composite material , thermodynamics
Polyvinylpyrrolidone (PVP) has been incorporated over the years into numerous hydrogel contact lenses as both a primary matrix component and an internal wetting agent to increase lens wettability. In this study, complementary analytical techniques were used to characterize the PVP wetting agent component of senofilcon A and samfilcon A contact lenses, both in terms of chemical composition and amount present. Photo‐differential scanning calorimetry (photo‐DSC), gas chromatography with a flame ionization detector (GC‐FID), and high‐resolution/accurate mass (HR/AM) liquid chromatography‐mass spectrometry (LC‐MS) techniques confirmed dual phase reaction and curing of the samfilcon A silicone hydrogel material. Gel permeation chromatography (GPC) demonstrated that high molecular weight (HMW) polymer was present in isopropanol (IPA) extracts of both lenses. High‐performance liquid chromatography (HPLC) effectively separated hydrophilic PVP from the hydrophobic silicone polymers present in the extracts. Collectively, atmospheric solids analysis probe mass spectrometry (ASAP MS), Fourier transform infrared (FTIR) spectroscopy, 1 H nuclear magnetic resonance (NMR) spectroscopy, GC‐FID, and LC‐MS analyses of the lens extracts indicated that the majority of NVP is consumed during the second reaction phase of samfilcon A lens polymerization and exists as HMW PVP, similar to the PVP present in senofilcon A. GC‐FID analysis of pyrolyzed samfilcon A and senofilcon A indicates fourfold greater PVP in samfilcon A compared with senofilcon A. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1064–1072, 2018.