Microfluidic in vitro Drug Release from Contact Lens Materials
Abstract
Purpose
Over 90% of ophthalmic drugs are commonly applied as eye drops. However, drug tear film residence time is less than 5 min, and only 5% of the administered drug is absorbed, leading to a final poor drug bioavailability and eventual side effects Efforts have been made to develop more effective drug delivery systems. Therapeutic contact lenses (CLs) have demonstrated to be a good vehicle for a controlled release of a variety of drugs owing to their biocompatibility, high degree of comfort, and prolonged contact with the eye.
Methods
CLs materials were prepared as a) a conventional hydroxyethylmethacrylate (HEMA) based hydrogel and as b) a silicone based hydrogel. The different materials were loaded with an antibiotic- levofloxacin (LVF), and one of two non-steroidal anti-inflammatory drugs (NSAID) -diclofenac (DCF) and ketorolac (KET). To simulate physiological human eye conditions such as temperature, tear volume and flow rate, drug release tests were carried out in a novel microfluidic cell.
Results
Results showed that a) HEMA based hydrogel allows a drug release up to 10 hours with predicted concentrations in the eye as >129 µg/mL for LVF, >918 µg/mL for DCF and > 251 µg/mL for KET whereas b) Silicone based hydrogel releases both NSAID for at least 4 days, with concentrations >163 µg/mL for DCF and >31 µg/mL for KET.
Conclusions
Drug eluted CLs biomaterials can be used as a platform for ocular drug delivery applications.
