In this study we report the preparation of novel multicomponent hydrogels as potential biomaterials for injectable hydrogels comprised of alginate, casein and bacterial cellulose impregnated with iron nanoparticles (BCF). These hydrogels demonstrated amide cross-linking of alginate–casein, ionic cross-linking of alginate and supramolecular interaction due to incorporation of BCF. Incorporation of BCF into the hydrogels based on natural biopolymers was done to reinforce the hydrogels and impart magnetic properties critical for targeted drug delivery. This study aimed to improve overall properties of alginate/casein hydrogels by varying the BCF loading. The physico-chemical properties of gels were characterized via FTIR, XRD, DSC, TGA, VSM and mechanical compression. In addition, swelling, drug release, antibacterial activity and cytotoxicity studies were also conducted on these hydrogels. The results indicated that incorporation of BCF in alginate/casein hydrogels led to mechanically stronger gels with magnetic properties, increased porosity and hence increased swelling. A porous structure, which is essential for migration of cells and biomolecule transportation, was confirmed from microscopic analysis. The porous internal structure promoted cell viability, which was confirmed through MTT assay of fibroblasts. Moreover, a hydrogel can be useful for the delivery of essential drugs or biomolecules in a sustained manner for longer durations. These hydrogels are porous, cell viable and possess mechanical properties that match closely to the native tissue. Collectively, these hybrid alginate–casein hydrogels laden with BCF can be fabricated by a facile approach for potential wound healing applications.

According to WHO’s Global report on diabetes 420 million adults are affected by diabetes worldwide. Foot infections are the most prevailing health complications in diabetics which arise due to neuropathy and peripheral vascular disease. The former concerns with nerve damage whereas the latter causes fatty depositions in blood vessels which reduce the blood flow causing pain, infection and slow healing wounds. One alternative therapy which is gaining popularity is the application of magnetic field to improve blood circulation by use of magnetic insoles. However, hydrogel based magnetic insoles have been scarcely reported. An efficient strategy is employed for the preparation of flexible magnetic hybrid hydrogels consisting of mixture of cobalt ferrite (CoFe2O4) and iron-oxide (Fe3O4) magnetic nanoparticles (MNPs) dispersed in PVP/CMC cross-linked hydrogels. Here the MNP ratio has been varied in the ratio of 1:0, 1:1, 1:2, 2:1 and 0:1, respectively. The method involves the formation of cross-linking between the two polymer chains under high pressure and temperature. The hybrid hydrogels were chemically and morphologically characterized using SEM, FTIR, VSM, swellability and mechanical testing. The morphological analysis showed the porous structure while using the VSM magnetic properties of the samples were evaluated. The rheological properties of the hydrogels were also investigated with the aim to verify their behaviour under an applied mechanical stress. The presence of MNPs, the hydrogel is capable of responding to an external magnetic field. Preliminary data show the possibility of use of the material for magnetic insoles for diabetics.