Synthesis and characterization of microparticles derived via a temporary inorganic core of carboxymethyl-cellulose/CaCO3 for the delivery of ocular medications — 16p — Maysa Gillingham, Caleb DeWitt, Winifred Mangwi

Many children and adults suffer from eye conditions that require topical eye medications for treatment; however, a large portion of the medication does not reach the eye due to corneal barriers and irrigation by tears. This project will investigate biopolymer microcapsules that can be integrated into a contact lens to increase the bioavailability of ocular medications and improve their retention on the surface of the eye. Additionally, the biopolymers yield benefits of their own such as moisture retention and wound healing properties. Calcium carbonate microparticles of the spherical, vaterite polymorph were synthesized with carboxymethylcellulose (CMC) incorporated, averaging 4-6 µm in size. The CMC incorporation provided a negatively charged interior and aided in polymorph retention. Once synthesized, the microparticles were subjected to layer-by-layer (LbL) treatment with oppositely charged biopolymers, hyaluronic acid and chitosan. The layered particles were then linked via amide bonds by using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), a carbodiimide coupler, and then the calcium carbonate cores were dissolved using hydrochloric acid. The microcapsules and microparticles were analyzed by ATR, PXRD, DLS, zeta potential, TGA, SEM, and optical microscopy. The hollow microcapsules (10-12 um) were incubated in a solution of norfloxacin and zingerone to test for drug retention in synthetic tear solutions.

Augustana University
Dr. Jetty Duffy-Matzner