Preparation and characterization of ionic and non-ionic surfactants impregnated.-carrageenan hydrogel beads for investigation of the adsorptive mechanism of cationic dye to develop for biomedical applications

In this work, the.-carrageenan (CRG) hydrogel beads were impregnated by polyethylene glycol tert-octylphenyl ether (Triton X-100, TTX), as a non-ionic surfactant, and sodium dodecylbenzene sulfonate (SDBS), as an ionic surfactant, in the presence of crosslinking agents of potassium chloride and aluminum chloride. The prepared hydrogel beads were examined by FTIR, XRD, SEM, BET, and TGA analysis, which well confirmed their successful impregnation by the surfactants. The results revealed that the spherical/cubic CRG-TTX hydrogels have a higher crystal structure and thermal resistance than spherical CRG-SDBS. It was demonstrated that the impregnation of CRG hydrogel beads with TXX and SDBS surfactants improves their adsorption behavior toward methylene blue (MB) from aqueous media. The surfactant amount significantly effects on adsorbent performance, whereas the best surfactant concentration was found to be half of the critical micellar concentration. The optimum concentration of adsorbents was obtained 1 g L-1, and the best removal efficiencies were achieved in the pH range of 4 to 8. The maximum adsorption capacity was obtained 482.15 mg g(-1) and 469.57 at 45 degrees C for CRGTTX and CRG-SDBS, respectively. The dye adsorption kinetics followed the pseudo-second-order kinetic model and the obtained adsorption experimental data were in good agreement with the Langmuir isotherm equation. Thermodynamic study indicated that the process was spontaneous in nature and endothermic. The polymeric microspheres can be employed to deliver drugs in a rate-controlled and sometimes targeted manner. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

In this study, CRG hydrogel beads were impregnated with surfactants to enhance their adsorption behavior towards methylene blue. The CRG-TTX hydrogels showed higher crystal structure and thermal resistance compared to CRG-SDBS. The concentration of surfactants significantly affected adsorption performance, with the best concentration found to be half of the critical micellar concentration.