Diffusion and Concentration Profiles for Loading DL-propanolol in a Crosslinked Drug Carrier, Poly(N-isopropyl acrylamide) Hydrogel

Abstract

As drug carriers, hydrogels feature the ability to hold a large quantity of a hydrophilic drug with highly tunable release profiles by adjusting the physicochemical properties of the polymer. Thermally sensitive polymeric hydrogels composed of poly (N-isopropylacrylamide) (PNIPAm) have attracted the attention of researchers recently due to its temperature-dependent phase transition properties. The drug in the present research was DL-propranolol hydrochloride, a synthetic beta-adrenergic receptor blocker. In this study the diffusion coefficient of drug in water was both modelled and experimentally determined The mass transfer experiment used a syringe method. UV-visible spectra of the DL-propoanolol showed a characteristic peak at 290 nm. The spectra at 8, 10 and 14 hours showed characteristic time dependent concentration profiles. An equilibrium partition coefficient was also measured at much longer times. These data will be used to parameterize a COMSOL-based model to understand the real-time loading of the drug in a massively arrayed microfluidic environment under continuous flows.