Manganese complex boosts electrode performance for guanine sensing

Chemists have synthesized a new manganese(II) complex containing 2,2′-bipyridine and hydrogen tartrate ligands, and report that a polymerized form of the compound substantially improves the performance of a glassy carbon electrode for detecting guanine oxidation. The work, published in BMC Chemistry, combined physicochemical, spectroscopic, electrochemical and antibacterial methods to characterize both a precursor compound, Na₂[Mn(HTA)₂Cl₂], and the final complex, [Mn(HTA)₂(2,2-bpy)].

The characterization relied on solubility testing, melting and decomposition behavior, molar conductance measurements, chloride testing, gravimetric manganese analysis, FTIR spectroscopy and UV–Vis spectroscopy. The available data support coordination of the tartrate-derived ligand through oxygen donor atoms and 2,2′-bipyridine through nitrogen donor atoms. The authors propose an octahedral coordination environment, although they note this geometry is proposed rather than definitively confirmed. The precursor and final complex showed molar conductance values of 255 and 299 S cm² mol⁻¹ respectively, indicating substantial ionic conductivity in water, though the authors caution that these values alone do not establish a definite electrolyte stoichiometry for the neutral final complex.

When poly([Mn(HTA)₂(2,2-bpy)]) was deposited on a glassy carbon electrode, the electroactive surface area increased from 0.15 to 0.44 cm², and the charge-transfer resistance dropped from 6266 to 273 Ω. The modified electrode also shifted the oxidation potential of guanine from 705 to 623 mV, a change that could make guanine detection easier in electroanalytical applications. Taken together, the authors conclude that these results support further investigation of the polymerized manganese complex as an electrode-modifying material.

The antibacterial arm of the study was far less conclusive. Testing at a concentration of 1000 ppm showed no measurable inhibition zones for the synthesized complexes, but the DMSO control also produced inhibition zones, complicating the interpretation. The authors therefore describe the antibacterial findings as preliminary and requiring confirmation using a solvent concentration that is itself inactive. Similarly, the proposed molecular structure of the complex requires additional validation.

Subject of Research: Synthesis and characterization of a manganese(II) bipyridine-tartrate complex for electrochemical guanine sensing and preliminary antibacterial testing

Article Title: Synthesis, characterization, electrochemical application, and antibacterial activity investigation of 2,2-bipyridineditartaratemanganese (II) complex

Article References: Desta, D. A., Metto, M., Teshager, M. A., Tigneh, G. T., & Abebe, A. (2026). Synthesis, characterization, electrochemical application, and antibacterial activity investigation of 2,2-bipyridineditartaratemanganese (II) complex. BMC Chemistry. https://doi.org/10.1186/s13065-026-01955-2

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DOI: 10.1186/s13065-026-01955-2

Keywords: manganese complex, 2,2-bipyridine, hydrogen tartrate, electrochemistry, glassy carbon electrode, guanine oxidation, charge-transfer resistance, FTIR spectroscopy, UV-Vis spectroscopy, antibacterial activity, BMC Chemistry, Synthesis