Physical And Chemical Properties Of 0.1% And 0.3% Sodium Hyaluronate Eye Drops: A Comparative Study

Objective: Compared physical and chemical properties of 0.1% and 0.3% sodium hyaluronate eye drops.Methods: Measure apparent viscosity by AR2000 rotational rheometer. Measure surface tension by dynamic contact angle measurement instrument DCAT21 PH value evaluated by PB-10 p H meter. Electrical conductivity evaluated by DDS-11 C conductivity meter. Seven healthy subjects were included. The continue reading test were taken on two inconsecutive days.Both subjective symptoms and inferior tear meniscus measurements were obtained before and 15, 30, 60, 120 minutes after instillation.Measure inferior tear meniscus by anterior segment optical coherence tomography. Various parameters of lower tear meniscus are analyzed by Imagepro-Plus(IPP).Various parameters are tear meniscus high(TMH), tear meniscus area(TMA), the angle between tear meniscus and cornea,the angle between tear meniscus and conjunctival.Results: The curve of the apparent viscosity changing with the shear rate in 32℃ is below when it is in 25℃. No matter 32℃ or 25℃, The curve of the apparent viscosity changing with the shear rate of 0.1% sodium hyaluronate eye drops is below the curve of 0.3% sodium hyaluronate eye drops. The surface tension of 0.1% and 0.3% sodium hyaluronate eye drops are close.With the temperature increases, the surface tension were falling, but very few. The p H value of 0.1% and 0.3% sodium hyaluronate eye drops are 6.24±0.04 and 6.31±0.02. The electrical conductivity of 0.1% and 0.3% sodium hyaluronate eye drops are 12.90±0.89ms/cm and 10.17±0.50ms/cm. No statistical differences were observed at each point before and 15, 30, 60, 120 minutes after instillation with different concentrations of sodium hyaluronate eye drops. Both subjective symptoms and lower tear meniscus area(TMA) and height are no statistical differences.Conclusion: Compared with 0.1% SH eye drops,0.3% SH eye drops can increase ocular surface retention time,but it does not affect the surface tension and subjective comfort,showing good fluid mechanics properties.