Pectin-based hydrogels with adjustable properties for controlled delivery of nifedipine: development and optimization

Pectin-co-poly acrylic acid (Pec-co-poly (AA)) hydrogels are imperative and new type of chemically cross-linked hydrogels. A research was conducted to develop pH-sensitive, controlled release, and biocompatible hydrogels by free radical polymerization and scrutinize the suitability of Pec-co-poly (AA) hydrogels as drug carriers. Different formulations were designed using central composite model. N,N-Methylenebisacrylamide (MBA) was used as a cross-linker and benzoyl peroxide (BPO) as an initiator. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) showed that hydrogels are thermally stable. Hydrogels have a porous structure, clearly expressed by scanning electron microscopy (SEM). Fourier transform infrared spectroscopy (FTIR) results concede the grafting reaction of AA on pectin. Hydrogels were figured out for pH-responsive behaviour by dynamic and equilibrium swelling ratio at low and high pH. The effects of pectin and acrylic acid (AA) content on swelling were also studied and revealed an increasing trend in swelling with increasing concentration of either pectin or AA. Similarly, developed hydrogels were also evaluated for different modalities for drug loading and release employing nifedipine as model drug. Constructed models are found to be suitable prediction tools, with contour plots and response surface plots providing an easy tool for estimation of response nature over entire setting of variables. It is concluded that highly stable Pec-co-poly (AA) hydrogels are developed. These have potential to be used as carrier for controlled delivery of nifedipine.