Synthesis and characterization of interpenetrating networks with tamarind kernel polysaccharide and polyacrylate for drug transport

Carboxymethylated tamarind kernel powder (CMTKP) was synthesized by reacting TKP (tamarind kernel polysaccharide) with monochloroacetic acid in the presence of sodium hydroxide. Semi-interpenetrating polymer networks (SIPN) based on poly-2-hydroxyethyl acrylate (PHEA) were synthesized with variable proportions of TKP and CMTKP, which were named as XTHEA21, XTHEA55, and CMTKP21, CMTKP55, respectively. CMTKP IPNs, being more ionic and hydrophilic, showed more swelling compared to the XTHEA types though the crosslink densities of the former were more in neutral medium and were loaded with less amount of drug (%). Glass transition points of the IPNs was controlled by the crosslinked density of it but not by the blend ratio as Tg of CMTKP55<Tg of CMTKP21. FTIR study confirmed the in-situ polymerization of HEA monomer and subsequent crosslinking in the presence of CMTKP, without any cross-reaction between the two polymers. Higher crosslink density of CMTKP IPNs compared to XTHEA samples caused smaller domains of dispersed phase, as exhibited in FESEM pictures, than that of the latter. CMTKP IPNs released the drug following “Super Case II transport phenomenon” (non-Fickian), which is the same as observed by the others, though XPHEA followed “Fickian Transport”.