We are celebrating an article featured by Environmental Science: Advances (IF=6.7). 

Abstract: Superabsorbent polymers (SAPs) are widely used in agriculture for water retention and in biomedical applications for controlled drug delivery. However, their use in environmental remediation, particularly for contaminated water treatment, and in analytical chemistry, as preconcentration materials, remains underexplored. In this work, commercial sodium polyacrylate beads (SAP beads) were systematically evaluated as sorbents for the removal and preconcentration of Cd(ii). The swelling behavior was studied as a function of ionic strength, pH, and temperature; revealing a strong polyelectrolyte character, with volumetric expansions up to 120-fold under low ionic strength and alkaline conditions. Kinetic analysis indicated a water diffusion-controlled process, with an activation energy of 16.2 kJ mol−1. Cd(ii) sorption kinetics and equilibrium studies revealed that metal sorption is coupled to the swelling process, with equilibrium reached after approximately 10 h. The sorption isotherm was described by the Langmuir model, with a maximum capacity of 128 mg g−1. The high sorption combined with reduced swelling at elevated Cd(ii) concentrations resulted in remarkable preconcentration performance, with concentration factors of up to 3500. Spectroscopic and microscopic analyses (FTIR, SEM, and EDS) confirmed the involvement of carboxylate groups in metal binding and revealed significant structural reorganization of the polymer matrix, including the formation of internal cavities. These results demonstrate that unmodified commercial sodium polyacrylate beads can function not only as water absorbents but also as efficient materials for Cd(ii) removal and preconcentration, with promising applications in environmental remediation and analytical chemistry.