Synthesis of poly (3-hydroxybutyrate)-comb-polyethylene glycol@TiO ₂ graft copolymer nanocomposite and their analytical practicality for adsorptive removal of safranin-O from water samples

This study reports the designing of comb-type polyethylene glycol (PEG)-functionalised poly (3-hydroxybutyrate)-@Titanium oxide (PHB-comb-PEG@TiO₂) through reversible addition-fragmentation chain transfer (RAFT) polymerisation approach for the first time and successfully used as a potential candidate for safranin-O (Saf-O) removal from water. The synthesised polymeric material was characterised by different techniques to examine the surface morphology, elemental analysis, surface functionality, and chemical structure of the prepared polymeric material by SEM, EDX, FTIR, and 1 h NMR. Different parameters such as pH, adsorbent dose, temperature, concentration, and equilibrium time were optimised during this study to enhance adsorption performance. The adsorption mechanism pattern and kinetic equilibrium time were best defined by the Langmuir and pseudo-second-order kinetics with a maximum adsorption capacity of 344.83 mg/g. A linear concentration range (10–150 μg/L) was obtained with a satisfactory low limit of detection (LOD) and the limit of quantification (LOQ) was achieved as 0.43 and 1.4 μg/L, respectively. The developed polymeric adsorbent was utilised successfully for the Saf-O removal from an aqueous medium. The results obtained suggest that the designed polymeric adsorbent could be a potential candidate in terms of its reusability, simplicity, high adsorption capacity, cost-effectiveness, excellent linear range, with fast kinetics.