In this research, the absorbance and luminescence response of two osmium(II) phenathrane (phen) carbonyl complexes to various DNA, heparin and i-carrageenan polyanions were studied. The [Os(phen)<sub>2</sub&g...In this research, the absorbance and luminescence response of two osmium(II) phenathrane (phen) carbonyl complexes to various DNA, heparin and i-carrageenan polyanions were studied. The [Os(phen)<sub>2</sub>CO(L)]<sup>2+</sup> complexes with L either a 4-phenyl pyridine (4-phpy) or phenyl imidazole (phimd) group exhibit moderate luminescent intensity in the visible region, their intensities are highly altered by the addition of DNA and other polyanion samples. These luminescent responses to polyanions were also compared with the [Ru(phen)<sub>3</sub>]<sup>2+</sup> complex. In ethanol solution, the presence of polyanions significantly enhanced the luminescent emission intensity of [Os(phen)<sub>2</sub>CO(L)]<sup>2+</sup> complexes with a blue shift. While the polyanions all showed emission enhancement on the highly lumi-nescent [Ru(phen)<sub>3</sub>]<sup>2+</sup> complex in ethanol solution with a red spectra shift. The [Os(phen)<sub>2</sub>CO(L)] <sup>2+</sup> with (phimd) ligand has the lowest emission in ethanol solution, its intensity can be enhanced up to 11 times in the presence of DNA polyanions. This enhancement for all the complexes in ethanol is mainly due to their electrostatic interaction with the anion sites and with some degree of ligand intercalation into the polyanion hydrophobic structure which reduced the solvent quenching of the complexes. The blue shift of the (4-phpy) and particularly (phimd) Os(II)CO complexes indicate an insertion of the (4-phpy) or (phimd) group into the polymer chains. The two new Os(II)CO complexes has great potential to be used as luminescence sensors for DNA and polyanion detection in the low micro molar range with high sensitivity.展开更多
To explore the spectroscopic properties of pyridyl triazole Os(Ⅱ)complexes and how the substituent effects affect the spectroscopic properties of[Os(ptz)2L2](L=PH3;ptzH=(2-pyridyl)-1,2,4-triazole)(1),[Os(bptz)2L2](bp...To explore the spectroscopic properties of pyridyl triazole Os(Ⅱ)complexes and how the substituent effects affect the spectroscopic properties of[Os(ptz)2L2](L=PH3;ptzH=(2-pyridyl)-1,2,4-triazole)(1),[Os(bptz)2L2](bptzH=3-tert-butyl-5-(2-pyridyl)-1,2,4-triazole)(2),[Os(fptz)2L2](fptzH=3-(trifluoreomethyl)-5-(2-pyridyl)-1,2,4-triazole)(3),and[Os(fbtz)2L2](fbtzH=3-(trifluoreomethyl)-5-(4-tert-butyl-2-pyridyl)-1,2,4-triazole)(4),the density functional theory(DFT)method at the B3LYP level was used to optimize the geometrical structures in the ground and excited state.The absorption and emission properties of the dichloromethane solution were predicted at the time-dependent density functional theory(TD-DFT,B3LYP)level associated with the PCM solvent effect model,the transitions characters of them were assigned.Important correlations between substituent effects and emission spectra and the quantum yield have been obtained by comparing and analyzing the calculated results.展开更多
文摘In this research, the absorbance and luminescence response of two osmium(II) phenathrane (phen) carbonyl complexes to various DNA, heparin and i-carrageenan polyanions were studied. The [Os(phen)<sub>2</sub>CO(L)]<sup>2+</sup> complexes with L either a 4-phenyl pyridine (4-phpy) or phenyl imidazole (phimd) group exhibit moderate luminescent intensity in the visible region, their intensities are highly altered by the addition of DNA and other polyanion samples. These luminescent responses to polyanions were also compared with the [Ru(phen)<sub>3</sub>]<sup>2+</sup> complex. In ethanol solution, the presence of polyanions significantly enhanced the luminescent emission intensity of [Os(phen)<sub>2</sub>CO(L)]<sup>2+</sup> complexes with a blue shift. While the polyanions all showed emission enhancement on the highly lumi-nescent [Ru(phen)<sub>3</sub>]<sup>2+</sup> complex in ethanol solution with a red spectra shift. The [Os(phen)<sub>2</sub>CO(L)] <sup>2+</sup> with (phimd) ligand has the lowest emission in ethanol solution, its intensity can be enhanced up to 11 times in the presence of DNA polyanions. This enhancement for all the complexes in ethanol is mainly due to their electrostatic interaction with the anion sites and with some degree of ligand intercalation into the polyanion hydrophobic structure which reduced the solvent quenching of the complexes. The blue shift of the (4-phpy) and particularly (phimd) Os(II)CO complexes indicate an insertion of the (4-phpy) or (phimd) group into the polymer chains. The two new Os(II)CO complexes has great potential to be used as luminescence sensors for DNA and polyanion detection in the low micro molar range with high sensitivity.
文摘To explore the spectroscopic properties of pyridyl triazole Os(Ⅱ)complexes and how the substituent effects affect the spectroscopic properties of[Os(ptz)2L2](L=PH3;ptzH=(2-pyridyl)-1,2,4-triazole)(1),[Os(bptz)2L2](bptzH=3-tert-butyl-5-(2-pyridyl)-1,2,4-triazole)(2),[Os(fptz)2L2](fptzH=3-(trifluoreomethyl)-5-(2-pyridyl)-1,2,4-triazole)(3),and[Os(fbtz)2L2](fbtzH=3-(trifluoreomethyl)-5-(4-tert-butyl-2-pyridyl)-1,2,4-triazole)(4),the density functional theory(DFT)method at the B3LYP level was used to optimize the geometrical structures in the ground and excited state.The absorption and emission properties of the dichloromethane solution were predicted at the time-dependent density functional theory(TD-DFT,B3LYP)level associated with the PCM solvent effect model,the transitions characters of them were assigned.Important correlations between substituent effects and emission spectra and the quantum yield have been obtained by comparing and analyzing the calculated results.
