2023 AIChE Annual Meeting
Impact of Molecular Weight Ratio and Solubility on Dye Release from PEO-b-PCL Copolymer Films
Poly(ethylene-oxide)-b-poly(ε-caprolactone) (PEO-b-PCL) is an amphiphilic diblock copolymer that is biodegradable and FDA approved. PCL is highly biocompatible and hydrophobic; however, it becomes an effective drug delivery system when attached to hydrophilic PEO. Due to its biocompatibility and unique properties, PEO-b-PCL is currently being researched in terms of its sustained drug delivery applications for hydrophobic drugs. Using a solvent casting method, polymer films were created using both PEO(5,000 g/mol)-b-PCL(16,300 g/mol) (5k-16.3k) and PEO(5,000 g/mol)-b-PCL(10,000 g/mol) (5k-10k). Methyl red (MR), methyl orange (MO) and methylene blue (MB) dyes were used as drug surrogates. Films of 3% dye (wt dye:wt polymer) were incubated in DI water to study dye release over time with minimal PCL degradation at neutral pH. Dye release trends were determined through UV-Vis Spectroscopy. The components impacting release rates of PEO-b-PCL copolymer films include varying molecular weight ratios, type of dye used, and the subtle differences in the pH of the environment. In general, initial studies showed that MB released the fastest from films, and 5k-10k films released dye faster than 5k-16.3k films. Analyzing these trends with both previous and current data allows for a better understanding of the future applications of PEO-b-PCL in drug delivery.