Synthesis, characterization, antioxidant and biomolecular interaction of trivalent samarium complex of cyclohexane-1,4-dicarboxylic acid as a precursor for nanosized carbonates

Trivalent samarium complex of cyclohexane-1,4-dicarboxylic acid with hydrazine has yielded a complex of formula [Sm(C8H11O4)3(N2H4)0.5].4H2O at pH 5 in an alcohol medium. The results of characterization by analytical, Infrared, UV-Visible, thermal, micro elemental, and PXRD techniques indicate that hydrazine is present as a neutral ligand and acid is present as a mono-ionic species. The PXRD data substantiate the phase purity of the synthesized complex. An in vitro antioxidant study (DPPH (2,2-diphenyl-1-picrylhydrazyl) radical) was carried out to assess the free radical-scavenging ability and confirmed that the samarium complex possesses significant radical-scavenging activity with an IC50 value of 136.66 ± 0.87 μM, indicating that it has the capability to scavenge free radicals. The binding ability towards biomolecules such as calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) was determined, and it exhibited the highest activity. Further, they are found to decompose in the range of 350-515 ℃, producing the respective samarium carbonate as an end product, as evidenced by their FT-IR and PXRD data. The observed SEM results indicate the trivalent complexes employed as a precursor for the synthesis of nano-sized 20-30 nm rare-earth carbonates. KEY WORDS: Hydrazine, Precursors, Samarium carbonate, BSA and DNA binding, DPPH activity Bull. Chem. Soc. Ethiop. 2026, 40(5), 1057-1067 DOI: https://dx.doi.org/10.4314/bcse.v40i5.9