Acrylic acid grafted gelatin/LDH based biocompatible hydrogel with pH-controllable release of vitamin B12

Abstract In this work, gelatin-g-poly(acrylic acid) based pH-sensitive nanocomposite hydrogels incorporated with Layered Double Hydroxide (LDH) were developed. Using various spectroscopic techniques such as FTIR, XRD, SEM, EDX and TEM, the polymeric hydrogels were characterized. FTIR confirmed grafting of partially neutralized Acrylic Acid (AAc) on the backbone of Gelatin. Incorporation of LDH fillers inside the hydrogel matrix was established from XRD data. Inclusion of LDH resulted wrinkled morphology of the surface of the hydrogel from the SEM images. Formation of nanocomposites were further evaluated by TEM analysis which displayed significant change in the TEM morphology of the nanocomposite hydrogel. Using DLS, particle size for LDH were determined further and was found to be around 100 nm. Swelling value of the hydrogel was around 34 g/g. Biocompatibility results showed enhanced blood compatibility for the hydrogels. The controlled release studies performed using the hydrogels demonstrated vitamin B12 was released in Artificial Gastric Fluid (AGF) and in Artificial Intestinal Fluid (AIF) in a controlled manner. The release study was carried out for 7 h each and was evaluated using UV–visible spectrophotometer. From the curves, the cumulative release in AGF and AIF was found to be 24% and 31%, respectively.