Abstract
ABSTRACTPurposes: To identify the deposition of fine (≤2.5 μm diameter) particulate matter (PM) particles (PM2.5) on contact lens surfaces and to investigate the effects of such deposition on the oxygen permeability (OP) and refractive index (RI) of contact lenses.Methods: A total of 36 contact lenses, including rigid gas permeable (RGP) lens and soft contact lens (SCL), were investigated. RGP lens (n=12) and SCL (n=12) (experimental group) were incubated in a PM2.5 solution for 24 h, after which PM2.5-treated RGP lens (n=6) and SCL (n=6) were further washed for 1 h in phosphate-buffered saline (PBS). All lenses were examined by field emission scanning electron microscopy. OP and RI of all lenses were measured.Results: Average-sized PM2.5 particles deposited on RGP contact lens and SCL surfaces after immersion in the PM2.5 solution were 3.192 ± 1.637 and 2.158 ± 1.187/100 μm2, respectively. On RGP lens surfaces, we observed both large (≥2.5 µm diameter) and small (PM2.5) particles. PM2.5 particles were deposited in diffuse patterns, primarily along the honeycomb structural border of SCL, while no PM2.5 particles were found in the honeycomb hole of SCL surfaces. Washing in PBS removed the larger PM particles from RGP lens surfaces, but left copious amounts of PM2.5 particles. In contrast, nearly all PM particles were removed from SCL surfaces after PBS washing. OP values of RGP lens and SCL appeared to be unchanged by PM2.5 deposition. RI values increased in both RGP lens and SCL groups after PM2.5 deposition. However, these increases were not statistically significant, suggesting that PM2.5 deposition itself does not cause fluctuations in contact lens RI.Conclusions: Deposition of PM2.5 particles on contact lens surfaces varies according to lens material. PM2.5 particles deposited on SCL, but only large particles on RGP surfaces were able to be removed by washing in PBS and did not appear to alter OP and RI of either lens type.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
