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Here, we report the synthesis and characterization of a hydrogel based on ethylene glycol diglycidyl ether (EGDE) and 1,8-diamino-3,6-dioxaoctane (DA). Chemically stable Co(II) and Cu(II) coordination complexes were prepared with this nonsoluble polyelectrolyte, poly(EGDE-DA), and studied by ss-NMR, FT-IR, thermogravimetry, and microscopy. Mesopores were found in all the samples, the thermal stability of the polymer matrix was highly affected by the presence of metal ions, and the (13)C CP-MAS spectrum for the Cu(II)-complex evidenced a significant increase in the reticulation degree by Cu(II) ions. The catalytic activity of these materials on H2O2 activation was studied by electron spin resonance (ESR). The Co(II)-poly(EGDE-DA)/H2O2 heterogeneous system produced O2, an anion superoxide (O2(•)¯), and a hydroxyl radical (OH(•)), which diffused into the solution at the time that a decrease in pH was detected. In the same way, the Cu(II)-poly(EGDE-DA)/H2O2 heterogeneous system produced O2 and OH(•). H2O2 activation by the poly(EGDE-DA) complexes with Co(II) and Cu(II) were applied on the decolorization of solutions of the azo-dye methyl orange (MO). In the presence of 63 mM H2O2, 87% of MO was removed in 10 min with Cu(II)-poly(EGDE-DA) and in 110 min with Co(II)-poly(EGDE-DA). In addition, the pharmaceutical product epinephrine was partially oxidized to adrenochrome by the O2(•)¯ released from the Co(II)-poly(EGDE-DA)/H2O2 heterogeneous system.

Nanocomposites and hybrid materials of Ag−1,3,5benzenetricarboxylic acid metal−organic frameworks (MOFs) with Sand N-carbon quantum dots (CQDs) were synthesized and evaluated for their antibacterial activity against representative Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacterial strains using the qualitative disk-diffusion approach and the quantitative minimum inhibitory concentration test. The composites and hybrids were found to be nontoxic to living cells. The composite formation fostered a synergistic effect that enhanced their antibacterial activity compared with those of their pristine components. Charge transfer from AgMOF to CQDs facilitated the electrostatic interactions of the composites and hybrids with the bacterial cell membranes. Enhanced bactericidal activity was linked to morphological features (a nanorod-like morphology) and specific surface chemistry. The latter affected the release of silver. Silver on the surface of the MOFs rather than silver in the bulk was found to be important. The destruction of the MOF component in the extracellular environment led to the release of silver ions, which have a high affinity to S compounds of the cell physiology. The formation of metallic silver (Ag°) and silver sulfides (Ag 2 S) was suggested as essential for the ability of the composites and hybrids to inhibit bacterial growth. To the best of our knowledge, this is the first study that introduces the bactericidal effect of AgMOF−CQDs composites and hybrids.