Ionic liquid(IL),1-butyl-3-methylimdazoliuim chloride,was introduced into the chromazural S-aluminium spectrophotometric system for the first time which involves Triton X-100 as solubilizing agents.The presence of IL ...Ionic liquid(IL),1-butyl-3-methylimdazoliuim chloride,was introduced into the chromazural S-aluminium spectrophotometric system for the first time which involves Triton X-100 as solubilizing agents.The presence of IL resulted in a sensitivity increase of about 50%.Besides,IL also helped to eliminate the spume resulting from surfactant,which usually makes the analysis inconvenient.Molar absorptivity of the proposed system is 1.2×105 L·mol-1 ·cm-1 and maximum absorption wavelength occurred at 616 nm.Based on 3σ criterion,detection limit of 0.0016μg·mL-1 was obtained and Beer’s law was obeyed in the range of 0.002 μg·mL-1-0.2 μg·mL-1.The proposed method has been successfully applied to the determination of Al in tap water and food samples,with analytical results in good agreement with those by ICP-OES.The results of this study revealled that IL might be a potential sensitizer for spectrophotometric methods involving micellar media.展开更多
A copper(Ⅱ) complex 1 of a novel macrocyclic polyamine ligand with hydroxylethyl pendant groups, 4,11-bis(hydroxylethyl)-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (L) has been synthesized and ...A copper(Ⅱ) complex 1 of a novel macrocyclic polyamine ligand with hydroxylethyl pendant groups, 4,11-bis(hydroxylethyl)-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (L) has been synthesized and characterized. Rate enhancement for hydrolysis of p-nitrophenyl picolinate (PNPP) catalyzed by 1 was studied kinetically under Brij35 micellar condition. For comparision, the catalytic activity of corresponding copper(Ⅱ) complex 2 of non-substituted macrocyclic polyamine ligand, 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraaza-cyclotetradecane (L') toward the hydrolysis of PNPP was also investigated. The results indicate that the macrocyclic polyamine copper(Ⅱ) complex 1 effectively catalyzed the hydrolysis of PNPP, and the pendant ligand hydroxyl group or deprotonated pendant ligand hydroxyl group can act as catalytically active species in the reaction. A ternary Complex kinetic model involving metal ion, ligand and substrate has been proposed, and the results confirmed the reasonability of such kinetic model.展开更多
文摘Ionic liquid(IL),1-butyl-3-methylimdazoliuim chloride,was introduced into the chromazural S-aluminium spectrophotometric system for the first time which involves Triton X-100 as solubilizing agents.The presence of IL resulted in a sensitivity increase of about 50%.Besides,IL also helped to eliminate the spume resulting from surfactant,which usually makes the analysis inconvenient.Molar absorptivity of the proposed system is 1.2×105 L·mol-1 ·cm-1 and maximum absorption wavelength occurred at 616 nm.Based on 3σ criterion,detection limit of 0.0016μg·mL-1 was obtained and Beer’s law was obeyed in the range of 0.002 μg·mL-1-0.2 μg·mL-1.The proposed method has been successfully applied to the determination of Al in tap water and food samples,with analytical results in good agreement with those by ICP-OES.The results of this study revealled that IL might be a potential sensitizer for spectrophotometric methods involving micellar media.
基金Project supporter by the National Natural Science Foundation of China (Nos. 20173038, 20107004).
文摘A copper(Ⅱ) complex 1 of a novel macrocyclic polyamine ligand with hydroxylethyl pendant groups, 4,11-bis(hydroxylethyl)-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (L) has been synthesized and characterized. Rate enhancement for hydrolysis of p-nitrophenyl picolinate (PNPP) catalyzed by 1 was studied kinetically under Brij35 micellar condition. For comparision, the catalytic activity of corresponding copper(Ⅱ) complex 2 of non-substituted macrocyclic polyamine ligand, 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraaza-cyclotetradecane (L') toward the hydrolysis of PNPP was also investigated. The results indicate that the macrocyclic polyamine copper(Ⅱ) complex 1 effectively catalyzed the hydrolysis of PNPP, and the pendant ligand hydroxyl group or deprotonated pendant ligand hydroxyl group can act as catalytically active species in the reaction. A ternary Complex kinetic model involving metal ion, ligand and substrate has been proposed, and the results confirmed the reasonability of such kinetic model.