A new dual-wavelength dual-indicator catalytic kinetic spectrophotometric method for the determination of trace Ru(III)was studied.This method was based on Ru(III)-catalyzing oxidation of Arsenazo I and indigo carmine...A new dual-wavelength dual-indicator catalytic kinetic spectrophotometric method for the determination of trace Ru(III)was studied.This method was based on Ru(III)-catalyzing oxidation of Arsenazo I and indigo carmine by potassium bromate in sulfuric acid.The absorbances of the catalytic and noncatalytic systems were measured at 510 and610 nm,respectively.Under the optimum conditions,the linear range of determination is 0–0.12 lgáml-1and the detection limit is 1.21 9 10-4lgáml-1.The method was applied for the determination of trace Ru(III)in ore samples with satisfactory results.展开更多
A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and...A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and to determine CO formed during the microsomal metabolism of xenobiotics in vitro. The method can significantly eliminate the background interference in the assay media and increase the quantitative accuracy and the sensitivity. There is a good linear relationship between CO concentration in the range of 2～10 μmol·L 1 CO and the distance D between the first derivative peak at 415 nm amd valley at 426 nm with r=0.9999(n=5),the regression equation being C (mmol·L 1 )=17.6D 0.4, the detection limit lower than 0.1 μmol·L 1 CO. The average recoveries of CO from the assay system and the sample were 102.1%, RSD=2.9% (n=7) and 79.7%, RSD=6.8% (n=12),respectively. The RSD of within day was 4.4%(n=18),and the RSD of day to day was 6.1%(n=16). By this method, four trihaloanilines and one trihalobenzene were tested, the results showed that only 2,4,5 trifluoroaniline could be converted to CO by the incubation with rat hepatic microsomes, NADPH and oxygen, the ability of phenobarbital or dexamethasone to induce rat hepatic microsomes to catalyze CO formation was 3 or 8 times higher than that of the control.展开更多
hree wavelength spectrophotometry was used to determine the content ofbenoxinate hydrochloride.Using this method could effectively eliminate the devia-tion of background absorption caused by the change of concentratio...hree wavelength spectrophotometry was used to determine the content ofbenoxinate hydrochloride.Using this method could effectively eliminate the devia-tion of background absorption caused by the change of concentration and the errorof quantitative anaiysis caused by asymmetric peaks, and at the same time the lean-ing degree of base line was corrected.This method was simple, the recovery was98. 62% 101. 86% and the coefficient of variation was 0. 551%.展开更多
The present paper describes the preparation of new organic reagent 2-[2-（6-chloro benzothiazolyl） azo]-resorcinol （6-CIBTAR = LH2） and used for the spectrophotometric determination of traces microgram amount of ni...The present paper describes the preparation of new organic reagent 2-[2-（6-chloro benzothiazolyl） azo]-resorcinol （6-CIBTAR = LH2） and used for the spectrophotometric determination of traces microgram amount of nickel （II） and copper （II） was found to form Ni（II）-CIBTAR at pH 7.5 giving a green coloured complex with maximum absorption at wavelength 636 nm and copper （II） was found to from Cu（II）-CIBTAR at pH 6.5 giving green bluish coloured complex with maximum absorption at wavelength 648 nm. The molar absorptivity （~） of the complexes are 0.3695 ~ 104 L.moll-cml and 0.3933 ~ 154 L＇mol＇l.cm1 for Ni（II） and Cu（II） respectively. Calibration curves for the determination of nickel（II） and copper （II） conformed to beers law over the concentration rang of （1-20） μg.mL-1. The DL （detection limit）, RSD （relative standard deviations）, RE （relative errors） and recovery for Ni（II） and Cu（II） complexes were found to be D.L = 0.45, 0.61; R.S.D% = 1.81, 2.04; Erei% = 1.3, 0.86 and Re% = 98.7, 99.14 respectively. The analytical data show the metal to reagent ratio （mole ratio method; M：L） in Ni（II） and Cu（II） complexes are 1：2.展开更多
基金supported by the National Natural Science Foundation of China (No. 51273172)
文摘A new dual-wavelength dual-indicator catalytic kinetic spectrophotometric method for the determination of trace Ru(III)was studied.This method was based on Ru(III)-catalyzing oxidation of Arsenazo I and indigo carmine by potassium bromate in sulfuric acid.The absorbances of the catalytic and noncatalytic systems were measured at 510 and610 nm,respectively.Under the optimum conditions,the linear range of determination is 0–0.12 lgáml-1and the detection limit is 1.21 9 10-4lgáml-1.The method was applied for the determination of trace Ru(III)in ore samples with satisfactory results.
文摘A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and to determine CO formed during the microsomal metabolism of xenobiotics in vitro. The method can significantly eliminate the background interference in the assay media and increase the quantitative accuracy and the sensitivity. There is a good linear relationship between CO concentration in the range of 2～10 μmol·L 1 CO and the distance D between the first derivative peak at 415 nm amd valley at 426 nm with r=0.9999(n=5),the regression equation being C (mmol·L 1 )=17.6D 0.4, the detection limit lower than 0.1 μmol·L 1 CO. The average recoveries of CO from the assay system and the sample were 102.1%, RSD=2.9% (n=7) and 79.7%, RSD=6.8% (n=12),respectively. The RSD of within day was 4.4%(n=18),and the RSD of day to day was 6.1%(n=16). By this method, four trihaloanilines and one trihalobenzene were tested, the results showed that only 2,4,5 trifluoroaniline could be converted to CO by the incubation with rat hepatic microsomes, NADPH and oxygen, the ability of phenobarbital or dexamethasone to induce rat hepatic microsomes to catalyze CO formation was 3 or 8 times higher than that of the control.
文摘hree wavelength spectrophotometry was used to determine the content ofbenoxinate hydrochloride.Using this method could effectively eliminate the devia-tion of background absorption caused by the change of concentration and the errorof quantitative anaiysis caused by asymmetric peaks, and at the same time the lean-ing degree of base line was corrected.This method was simple, the recovery was98. 62% 101. 86% and the coefficient of variation was 0. 551%.
文摘The present paper describes the preparation of new organic reagent 2-[2-（6-chloro benzothiazolyl） azo]-resorcinol （6-CIBTAR = LH2） and used for the spectrophotometric determination of traces microgram amount of nickel （II） and copper （II） was found to form Ni（II）-CIBTAR at pH 7.5 giving a green coloured complex with maximum absorption at wavelength 636 nm and copper （II） was found to from Cu（II）-CIBTAR at pH 6.5 giving green bluish coloured complex with maximum absorption at wavelength 648 nm. The molar absorptivity （~） of the complexes are 0.3695 ~ 104 L.moll-cml and 0.3933 ~ 154 L＇mol＇l.cm1 for Ni（II） and Cu（II） respectively. Calibration curves for the determination of nickel（II） and copper （II） conformed to beers law over the concentration rang of （1-20） μg.mL-1. The DL （detection limit）, RSD （relative standard deviations）, RE （relative errors） and recovery for Ni（II） and Cu（II） complexes were found to be D.L = 0.45, 0.61; R.S.D% = 1.81, 2.04; Erei% = 1.3, 0.86 and Re% = 98.7, 99.14 respectively. The analytical data show the metal to reagent ratio （mole ratio method; M：L） in Ni（II） and Cu（II） complexes are 1：2.
