*WINNER* Partition Factor for a Drug in PNIPAm Hydrogel and Water

Abstract

Taking medication often comes with side effects which range in severity which may even deter people from seeking treatment. Accordingly, there is a need for improved efficiency in drug delivery which can be achieved with the use of a nanoparticle drug delivery system. In order to manufacture drug delivery hydrogel particles at a nanoscale, the behavior of the system must first be understood fundamentally. This study focused on quantifying the amount of a drug, chosen to be DL-propranolol hydrochloride, that diffuses into a poly(n-isopropylacrylamide) (PNIPAm) hydrogel at equilibrium. Three gels were synthesized and soaked in a solution containing DL-propranolol hydrochloride for 14 days, which was found to be the amount of time needed for the drug to reach equilibrium (complete diffusion). After this time period, the gels were then sliced into disks in order for the drug to be extracted. Using UV-visible spectroscopy, the concentration of drug in each disk was analyzed. This data, along with the concentration of the drug in the solution, gave an average partition coefficient for DL-propranolol hydrochloride in a poly(n-isopropylacrylamide) hydrogel as 0.5861. This number is indicative of one aspect of the behavior of a nanoparticle drug delivery system that will be produced in future work.