Modification of hydrophilic polymer network to design a carrier for a poorly water-soluble substance

pH sensitive, nontoxic, and biocompatible poly(methacrylic) acid (PMAA) based soft networks have been extensively used in the design of systems for targeted drug delivery. Still, their highly hydrophilic nature limits their potential to be used as a carrier of poorly water-soluble substances. With the aim to overcome this limitation, the present study details a new approach for modification of PMAA based carriers using two amphiphilic components: casein and liposomes. The FTIR analysis revealed structural features of each component as well as the synergetic effect that originated from the formation of specific interactions. Namely, hydrophobic interactions between the poorly water-soluble model drug (caffeine) and casein enabled caffeine encapsulation and controlled release, while addition of liposomes ensured better control of the release rate. The morphological properties of the carriers, swelling behavior, and release kinetics of caffeine were investigated depending on the variable synthesis parameters (neutralization degree of methacrylic acid, concentration of caffeine, presence/absence of liposomes) in two different media simulating the pH environment of human intestines and stomach. The data obtained from in vitro caffeine release were correlated and analyzed in detail using several mathematical models, indicating significant potential of investigated carriers for targeted delivery and controlled release of poorly water-soluble substances.