Anti-PPY polyclonal antibody

Two cationic iridium(iii) complexes, [Ir(ppy)(2)((tdzp))](+)(1) and [Ir(bhq)(2)((tdzp))](+)(2) {ppy = 2-phenylpyridine, bhq = benzo[h]quinoline, tdzp = [1,2,5]-thiadiazolo-[3,4-f]-[1,10]-phenanthroline}, have been synthesized and structurally characterized. The molecular structures of the iridium complexes have been confirmed by single-crystal X-ray structure determination. Extensive hydrogen bonding between lattice water molecules, solvated methanol, and chloride anions is observed in the crystal structure of complex1, which leads to the formation of 1D polymeric cyclic hybrid water-chloride-methanol clusters. The complexes show different photophysical properties in different solvents. The experimental photo-physical properties of the synthesized iridium(iii) complexes match well with the theoretically calculated results obtained by density functional theory (DFT) and time-dependent density functional theory (TD-DFT) studies. The HOMO of complexes1and2is restricted on the iridium and cyclometalated aromatic ligands, while the LUMO, LUMO+1, and LUMO+2 are primarily restricted on the polypyridyl tdzp ligand. The interaction of the complexes with calf thymus DNA (CT-DNA) was investigated by absorption titration and emission titration experiments. Furthermore, the cytotoxicity and cellular localization properties of these complexes towards HeLa cells have been investigated.

Herein, we report the effects of different electron-withdrawing groups (EWG) (-F) and electron-donating groups (EDG) (-OMe and -NH2) on main ligands (ppy) and ancillary (acac) of [Ir(ppy)(2)(acac)] [ppy = 2-phenylpyridine; acac = acetylacetonato] using seven complexes by DFT and TDDFT calculations. We find that irrespective of the substituents, absorption of ppy-substituted complexes is blue-shifted, while for the acac-substituted complexes, it is red-shifted. The calculations also show that the substitution of EWGs causes an overall drop in the frontier molecular orbital energy levels; however, we observed a reverse effect for EDGs. To calculate the radiative rate k(r), we considered the spin-orbit coupling matrix element (SOCME) (< T-1 vertical bar H-SOC|S-n >) between S-n (n = 1, 2, etc.) excited state and T-1, transition dipole moment (mu(S-n)), and the energy difference between excited singlet states S-n and T-1 state (Delta E(S-n - T-1)). To compare the temperature-independent nonradiative process, we considered SOC between T-1 and S-0 (< T-1 vertical bar H-SOC vertical bar S-0 >) and the energy gap between optimized T-1 and S-0 states. Furthermore, to formulate the temperature-dependent nonradiative rate, we computed the activation barrier (E-1) for the metal-to-ligand state ((MLCT)-M-3) to a metal-centered state ((MC)-M-3) conversion. The emission peaks show that the changes of triplet state T-1 from (MLCT)-M-3. (MC)-M-3 via transition states ((TS)-T-3) and (MLCT)-M-3 -> (1)GS (GS = ground state) via the (MC)-M-3/(1)GS minimum energy crossing point are not much affected by the nature of substituents in the ancillary and the main ligand. The order of E-1 for the investigated complexes indicates that electron-donating substituents -OMe at both ppy and acac ligands can cause a decrease in nonradiative rate constants. Natural transition orbitals of the complexes show that they are mainly localized on the main ligand ppy and the Ir atoms and hardly on the ancillary ligand acac.