Robust fabrication of pyrogallol-conjugated dextran hydrogel as antioxidant hemo-adsorbent for the selective adsorption of Pb(II)

Adsorbents with high adsorption capacity, selectivity, and antioxidant activity are crucial to enhance the efficacy and prognosis of hemoperfusion treatments for patients with lead poisoning. This study presents the development of polyphenol-analogous dextran hydrogels (PYG@Dex) with abundant chemically conjugated pyrogallol (PYG) groups on their networks, which were prepared by Hantzsch cross-linking reaction involving the formation of 1,4-dihydropyridine from acetoacetylated dextran, 3,4,5-trihydroxybenzaldehyde, and NH 4 OAc. The resulting PYG@Dex hydrogel exhibited superior biocompatibility and robust antioxidant capabilities, achieving a free radical scavenging rate of over 90 %. Notably, the hydrogel with high PYG content displayed an outstanding adsorption capacity of 102.35 mg·g −1 for Pb 2+ ions, due to the coordination interactions with PYG and β -ketoester groups. The adsorption affinity of PYG@Dex for Pb 2+ ions was confirmed in the presence of biologically-relevant metal ions (K + , Na + , Ca 2+ , and Mg 2+ ) in both aqueous solutions and simulated plasma. These findings underscore the potential of PYG-conjugated hydrogels to address the challenges of selective heavy metal removal from blood through hemoperfusion and to provide additional protection against heavy metal-induced oxidative stress responses.