Three-dimensional, time-dependent analysis of metallic ion adsorption in alginate hydrogels using laser-induced breakdown spectroscopy

Abstract

[Abstract]: This study examines the adsorption behavior of selected metal ions—Ni2+, Cu2+, Zn2+, Pb2+, Cr3+, and Cd2+—by dried alginate hydrogels using laser-induced breakdown spectroscopy. The investigation includes both single-ion and multi-ion samples, highlighting the technique's potential for simultaneous detection and depth-profiling measurements. The results demonstrate that adsorption is a kinetically driven process, extending beyond the hydrogel surface to permeate the entire bulk structure. These findings provide evidence of uniform ion distribution within the hydrogel network, thereby advancing our understanding of its adsorption mechanisms. Furthermore, this work highlights the potential of laser-induced breakdown spectroscopy as a cost-effective, low sample consumption and highly sensitive analytical alternative to conventional methods, such as inductively coupled plasma mass spectrometry and atomic absorption spectroscopy, for metal ion detection in hydrogel systems.