In vitro release of metformin from iron (III) cross-linked alginate-carboxymethyl cellulose hydrogel beads

In the present study, sodium alginate (NaAlg)/sodium carboxymethyl cellulose (NaCMC) blend hydrogel beads were prepared in ferric chloride solution. The developed hydrogel beads exhibited pH sensitive for deliver Metformin hydrochloride (MH). Preparation conditions of the beads (ferric chloride solution) were significantly affected the encapsulation efficiency, swelling and in vitro release profiles of the beads. Swelling studies were accomplished in gastric and intestine stimuli atmosphere at 37°C. The swelling studies reveal that the beads at pH 7.4 showed higher swelling properties compare to pH 1.2. Exterior morphology of beads was analyzed by scanning electron microscope. SEM indicates the surface of the beads is spherical with smooth surface and size of beads drastically reduced with increasing crosslinker concentration. The crosslinking reaction between NaAlg and NaCMC with ferric chloride was confirmed by FTIR analysis. XRD analysis indicates that MH drug molecularly dispersed in the polymer matrix. In vitro release studies of MH loaded beads showed higher release profiles at pH 7.4 compared to pH 1.2. The polymeric matrices followed slightly deviation with Fickian diffusion and fit for experimental co-relation (r²) values.