Revisiting adsorption of biomolecules on polymeric resins

Adsorptive interactions of certain alkaloid and beta-lactam antibiotic onto polymeric resins such as Amberlite XAD-4, XAD-7 and Diaion HP2MG have been studied using FT-IR Spectroscopy and Scanning Electron Microscopy (SEM) techniques with the aim of in-depth understanding of the adsorption mechanism. IR studies show that there may be participation of some functional groups in the adsorption of caffeine and cephalosporin-C onto Amberlite XAD-4. SEM studies revealed the morphological observations of the unloaded adsorbent and thereby changes in the adsorbed polymeric resins. It was found that the adsorption of biomolecules onto polymeric resins may not be only due to hydrophobic interaction, a specific solute–sorbent interaction involving π-electron on the sorbent surface may also dominate the adsorption mechanism.