Interpenetrating Polymer Networks of Poly(2-hydroxyethyl methacrylate) and Poly(N, N-dimethylacrylamide) as Potential Systems for Dermal Delivery of Dexamethasone Phosphate

Abstract

In this study, a series of novel poly(2-hydroxyethyl methacrylate) (PHEMA)/poly(N,N′-dimethylacrylamide) (PDMAM) interpenetrating polymer networks (IPNs) were synthesized and studied as potential drug delivery systems of dexamethasone sodium phosphate (DXP) for dermal application. The IPN composition allows for control over its swelling ability as the incorporation of the highly hydrophilic PDMAM increases more than twice the IPN swelling ratio as compared to the PHEMA single networks, namely from ~0.5 to ~1.1. The increased swelling ratio of the IPNs results in an increased entrapment efficiency up to ~30% as well as an increased drug loading capacity of DXP up to 4.5%. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) show the formation of a solid dispersion between the drug DXP and the polymer (IPNs) matrix. Energy-dispersive X-ray (EDX) spectroscopy shows an even distribution of DXP within the IPN structure. The DXP release follows Fickian diffusion with ~70% of DXP released in 24 h. This study demonstrates the potential of the newly developed IPNs for the dermal delivery of DXP.

Recent Advances in Micro- and Nano-Drug Delivery Systems Based on Natural and Synthetic Biomaterials

“…There are two older alternatives to PHEMA: agar and agarose gels [33]. For the purpose of developing drug delivery systems, equilibrium swelling, structural characterization, and solute transports in swollen PHEMA gels cross-linked with tripropyleneglycol diacrylate (TPGDA) were investigated across a large TPGDA concentration range [34]. In order to get a better understanding of the mechanism of drug-polymer interaction and its influence on the drug-release behaviour of controlled-release polymeric devices, the physical and chemical features of pilocarpine extracted from PHEMA hydrogels were investigated.…”