Graft-copolymer of polyacrylamide-tamarind seed gum: Synthesis, characterization and evaluation of flocculating potential in peroral paracetamol suspension

In the present study, polyacrylamide-grafted-tamarind seed gum (PAAm-g-TSG) was synthesised employing free radical method assisted with microwave where cerric (IV) ammonium nitrate (CAN) was used as free radical initiator. Effects of monomer, CAN and microwave irradiation time (MW) on grafting were studied. Various grafting indicators such as % grafting (%G), % grafting efficiency (%GE) and % conversion (%Cn) were calculated. MW and CAN exhibited major contribution in the synthesis. Highest % grafting (890.3%) was shown in the batch with 10 g acrylamide, 400 mg CAN and 1 min MW. Grafted TSG was then characterized by elemental analysis, FTIR, solid state 13C NMR, DSC, TGA, XRD, viscosity, SEM, acute oral toxicity and biodegradability study. Nontoxic and biodegradable natures of PAAm-g-TSG were revealed in the study. Finally, flocculating property of the grafted gum was evaluated in paracetamol suspension. The flocculation study demonstrates that all batches of graft copolymer showed to have good flocculating efficiency in paracetamol suspension and the capacity increases with increase in both concentration and grafting. S11 batch (highest %G = 890.3) exhibited highest degree of flocculation (β = 5.14 ± 0.26) among others.