Characterization of 2,3,6,7,10,11-hexahydroxytriphenylene and its effects on cell viability in human cancer cell lines

Abstract

We synthesized 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP), characterized it by electrochemistry, spectroelectrochemistry, and electron paramagnetic resonance techniques, and evaluated its cytotoxicity to human cancer cell lines. The results revealed that HHTP has accessible higher-oxidation states, especially the tris-semiquinone monoradical. This species is stable and is formed after being stored for months. HHTP exhibited cytotoxic effects on 5 human cancer cell lines, including glioma and lung cancer cells. The cytotoxic effect was evaluated based on the decrease in cell viability, increases in the percentage of cells with fragmented DNA, and elevated numbers of annexin V-PI-positive cells after HHTP treatment.

Conductive Metal–Organic Frameworks as Ion-to-Electron Transducers in Potentiometric Sensors

“…Additional analysis using CV (Figure S8 and associated discussion) revealed that the electrochemical behavior of M 3 HHTP 2 MOFs was influenced by the identity of the metal centers embedded within the MOFs, as evidenced by the characteristically different CV profiles for Ni 3 HHTP 2 , Cu 3 HHTP 2 , and Co 3 HHTP 2 MOFs (Figure S8). The observed voltammetric behavior may be explained by the redox activity of HHTP ligand that can undergo reversible redox transformations between catechol, semiquinone, and quinone forms . Given that MOFs exhibit permanent porosity, changes in the cumulative pore volume as a function of the MOF layer thickness may be further manifested by the unique voltammetry of these materials …”

“…The observed voltammetric behavior may be explained by the redox activity of HHTP ligand that can undergo reversible redox transformations between catechol, semiquinone, and quinone forms. 72 Given that MOFs exhibit permanent porosity, changes in the cumulative pore volume as a function of the MOF layer thickness may be further manifested by the unique voltammetry of these materials. 73 We hypothesize that the electrochemical double-layer charging, characterized by the rectangular shape of the potential−current response, plays a role in the capacitive behavior of of Ni 3 HHTP 2 and Co 3 HHTP 2 MOF-based ISEs.…”

Employing Conductive Metal–Organic Frameworks for Voltammetric Detection of Neurochemicals

“…HHTP/HITP constituents may also undergo reversible redox transformations. 77,131 We hypothesize that the observed distinct redox transitions for all studied M 3 HXTP 2 MOFs may originate from the following: (i) redox activity of the metallic nodes or/and organic linkers; 132−134 (ii) coexistence of several active redox states due to the presence of defects in the MOF lattice (e.g., exposed-edges); 137 and (iii) redox-active impurities that are permanently incorporated within the bulk of the porous framework, but are not observable by pXRD or XPS.…”

Room-Temperature Quantitative Quantum Sensing of Lithium Ions with a Radical-Embedded Metal‒Organic Framework

“…These g values are typical for phenoxyl radicals. 45 Quantitative CW EPR analysis revealed that 1-2% of HOTP ligands contain a radical (Figures S11, Table S2-S3), corresponding to an electron spin concentration between 2 × 10 -2 mol/L and 4 × 10 -2 mol/L. Note that saturated solutions of the free-ligand HHTP in typical organic solvents such as tetrahydrofuran (THF) do not show observable CW or pulsed EPR signals.…”

“…The tritopic ligand 2,3,6,7,10,11hexahydroxytriphenylene (HHTP) is a common building block in two-dimensional (2D) porous MOFs, 44 whose spontaneous oxidation generates a radical. 45,46 Using EPR spectroscopy, we demonstrate that the radicals in MgHOTP behave as electron spin qubits, whose quantum states can be partially polarized by an external magnetic field, manipulated by microwave pulses, and read out through electron spin echo schemes. We further demonstrate quantitative detection of lithium ions (Li + ) in solution at room temperature using MgHOTP qubits with relaxometry and hyperfine spectroscopy.…”