Oxygen permeability and water content of silicone hydrogel ... | 合法醫療器材資訊網

由NEfron著作·2007·被引用132次—Purpose:Tomeasuretheoxygenpermeability(Dk)andwatercontent(WC)ofsiliconehydrogel(Si-Hy)contactlensmaterials.Methods:Randomizedand ...

Purpose: To measure the oxygen permeability (Dk) and water content (WC) of silicone hydrogel (Si-Hy) contact lens materials.

Methods: Randomized and masked determinations of the Dk of 5 Si-Hy and two hydrogel materials were made using a modified version of the polarographic measurement method described in ISO 9913-1. Stacks of one to six parallel-sided contact lenses (all -1.00 DS) were evaluated, with each stack measured at least twice. The resulting value for t/Dk was plotted against the thickness (t) of each stack, with Dk calculated as the inverse of the gradient of this relationship. This methodology corrects for boundary effects. A mathematical calculation was used to correct for edge effects. Gravimetric determination of lens WC was conducted at room temperature and 35 degrees C.

Results: Measured values (+/-95% CI) of Dk, and WC at room temperature, with manufacturer-claimed...