Understanding the adsorption and potential tear film stability properties of recombinant human lubricin and bovine submaxillary mucins in an in vitro tear film model

• Published in: Colloids and surfaces, B, Biointerfaces B, Biointerfaces, 2020-11, Vol.195, p.111257-111257, Article 111257
• Main Authors: Rabiah, Noelle I., Sato, Yasunori, Kannan, Aadithya, Kress, Wolfgang, Straube, Frank, Fuller, Gerald G.
• Format: Article
• Language: English
• Subjects: 60 APPLIED LIFE SCIENCES; Adsorption; Dry eye; Fluid film stability; Lubricin; Marangoni flow; Mucins; QCM-D; Tear film; Wettability
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2020.111257

[Display omitted] •rh-Lubricin and BSM solutions are evaluated as a model tear film in custom platform.•The mucin-rich fluid films resist breakup through evaporation-driven Marangoni flow.•rh-Lubricin adsorbs on surfaces more effectively than BSM.•The neutral surface charge and size of rh-lubricin may contribute to enhanced adsorption. The wetting and adsorption properties for two glycoproteins, recombinant human lubricin and bovine submaxillary mucins (BSM) were evaluated on hydrophilic and hydrophobic glass dome surfaces in a simplified in vitro tear film model. We show that both recombinant human lubricin (rh-lubricin) and BSM solutions render surfaces hydrophilic and when the fluid films reach 500 nm or less, the fluids resist evaporation-driven breakup through a volumetric flux across the surface, which we believe is due to evaporation-driven solutocapillary flows. rh-Lubricin was able to maintain a wet film without spontaneous breakup for longer periods of time than BSM at lower concentrations, which we attribute to differences in adsorption properties, measured by QCM-D, that result from surface charge and structural differences (confirmed by zeta potential, DLS, and SAXS measurements).