Water soluble drug releasing soft contact lens in response to pH of tears

International Conference on Chemical and Bioprocess Engineering

地球科学;化学;生物科学

Kim, G.^1 ; Noh, H.^1,2

Convergence Institute of Biomedical Eng. and Biomaterials, Korea, Republic of^1

Department of Optometry, Seoul National University of Science and Technology, Korea, Republic of^2

关键词: Environmental factors;    Hydrogel contact lens;    Hydrogel networks;    Methyl cellulose;    Physiological concentrations;    Physiological pH;    Soft contact lens;    Water soluble drugs;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/36/1/012057/pdf
DOI  :  10.1088/1755-1315/36/1/012057

学科分类：生物科学（综合）

来源: IOP

【 摘 要 】

Human tear characteristics including pH and compositions can vary significantly depending on physical and environmental factors. Contact lenses directly contact with human tears can be swelled or de-swelled depending on the pH of the solution due to the nature of the hydrogel. For examples, anionic hydrogels, when the solution's pH is low, is shrunken due to the electric attraction force within the hydrogel network; the opposite phenomenon appears when the solution is basic. The purpose of this study was to evaluate the extent of water soluble drug, hydroxyl propyl methyl cellulose, released from contact lens according to the pH of the artificial tears. Artificial tears are prepared by mixing lysozyme, albumin, sodium chloride, potassium chloride, and calcium chloride following physiological concentrations. Hydrogel contact lens was thermally polymerized using HEMA, EGDMA, and AIBN. The prepared hydrogel lens was immersed in drug for 3 hours and the eluted drug mass was measured as a function of the time. As a result, the drug was released from the lens for 12 hours in all the pH of artificial tears. At the lower pH of artificial tears (pH 5.8), the total amount of dye emitted from the lens was increased than the total amount of dye emitted at the basic tear (pH 8.4). Also, initial burst at acidic tears was increased within 1 hour. Release pattern of water-soluble drug from hydrogel lens turned out to be different depending on the pH of the artificial tears. When designing drug releasing contact lens, physiological pH of tears should be considered.