Adsorption of Metformin hydrochloride and sodium diclofenac over Gum ghatti-g-poly(NIPAM-co-AA)/-o-MWCNT

Abstract

The current concern over water pollution caused by various agents is significant. The predominant method for removing pollutants involves adsorption, with biopolymer-based hydrogels being widely utilized for this purpose. In this study, the amalgamation of N-isopropylacrylamide (NIPAM) and acrylic acid (AA) was performed on the surface of gum ghatti (GG), scientifically identified as Anogeissus latifolia. The grafting of PNIPAM and PAA was achieved using the free radical initiator ammonium persulfate (APS). Initially, APS generated reactive sites on GG, leading to the grafting of PNIPAM and PAA. A modified version of oxidized multi-walled carbon nanotubes (o-MWCNT) was incorporated onto GG-g-P(NIPA-co-AA) in situ. Material characterization using FT-IR and XRD confirmed the formation of GG-g-P(NIPA-co-AA) and the presence of o-MWCNT. The hydrogel GG-g-P(NIPAM-co-AA)/o-MWCNT(30 mg)-GNACNT-3 exhibited favourable simultaneous adsorption of sodium Metformin hydrochloride (MF) and sodium diclofenac (SD) under varied conditions using a batch adsorption process. The results indicated a higher adsorption affinity for SD compared to MF, with 40 mg of adsorbent showing greater efficiency for SD (89.2%) than MF (60.41%). The adsorption of both drugs followed the Langmuir adsorption isotherm and Pseudo-2nd-order kinetic model, suggesting a monolayer and chemisorption mechanism.

Keywords

• Adsorption
• N-isopropyl acrylamide
• Acrylic acid
• Multi-walled carbon nanotubes
• Metformin hydrochloride
• Sodium diclofenac