A rapid,sensitive and simple spectrofluorimetric method was developed for the estimation of atorvastatin.In this method,the native fluorescence characteristics of atorvastatin have been studied in both acidic and basi...A rapid,sensitive and simple spectrofluorimetric method was developed for the estimation of atorvastatin.In this method,the native fluorescence characteristics of atorvastatin have been studied in both acidic and basic media.High sensitivity was obtained with 5% acetic acid at 389 nm using 276 nm for excitation.Regression analysis showed a good correlation coefficient(r=0.9995) between fluorescence intensity and concentration over the range of 1.5-4 mg/mL with detection limit of 0.012 mg/mL.The proposed method was successfully applied to the analysis of atorvastatin in pure and pharmaceutical dosage forms with average recovery of 100.2970.47%.The results were compared favorably with those of the reported method.展开更多
A spectrofluorimetric method for the determining riboflavin (VB2) based on its enhancement on the fluorescence of hemoglobin-catalyzed enzymatic reaction was proposed. The proposed method consisted of two reactions. O...A spectrofluorimetric method for the determining riboflavin (VB2) based on its enhancement on the fluorescence of hemoglobin-catalyzed enzymatic reaction was proposed. The proposed method consisted of two reactions. One was the photochemical reaction of VB2, the other was a hemoglobin-catalyzed enzymatic reaction. The optimal experimental conditions for the determinations were established. The linear range of the method was 5.0×10?9?1.0×10?7 mol/L of VB2. The detection limit was calculated to be 3.65×10?9 mol/L. The relative standard deviation of this method was 2.3%at 7.0×10?2 mol/L for 11 determinations.展开更多
Abstract: Terbium can form a stable binary chelate with terephthalic acid (benzene-1. 4-dicarboxylic acid(TPA) ) having a ratio of 1: 2 in aqueous solution in the pH range of 5～6. The maximum excitation and emission ...Abstract: Terbium can form a stable binary chelate with terephthalic acid (benzene-1. 4-dicarboxylic acid(TPA) ) having a ratio of 1: 2 in aqueous solution in the pH range of 5～6. The maximum excitation and emission wavelengths are 260 nm and 545 nm for terbium chelate, respectively. The fluorescence intensity of terbium chelate remains stable in 8h with a relative standard deviation in the range of =4X. The rest of the lanthanide ions and the common foreign ions hardly interfere the determination.展开更多
A new spectrofluorimetric method for determination of trace terbium based on its reaction with 2.6-his-(1'-phenyl-3'-methyl-5'- pyridinediacyl (H_2PMBPP) and N- cetylpyridium bromide (CPB). at an apparent ...A new spectrofluorimetric method for determination of trace terbium based on its reaction with 2.6-his-(1'-phenyl-3'-methyl-5'- pyridinediacyl (H_2PMBPP) and N- cetylpyridium bromide (CPB). at an apparent pH=5.0 provided by a hexamethylenetetramine (5% w/w)-hydrochloric acid buffer,is propesed. The calibration graph is linear in the ran ge from展开更多
A highly sensitive and fairly selective spectrofluorimetric method has been developed for the determination of germanium with morin in tap water and health drink. The fluorescent reaction and optimal conditions of ger...A highly sensitive and fairly selective spectrofluorimetric method has been developed for the determination of germanium with morin in tap water and health drink. The fluorescent reaction and optimal conditions of germanium with morin in phosphoric acid medium were studied. The detection limits of germanium in tap water and health drink were found to be 0.2 and 0.7μd/L respectively.展开更多
The development of the spectrofluorimetric method can be considered a promising alternative that is relatively less expensive and sufficiently reliable. In the current literature, no method for the analysis of nevirap...The development of the spectrofluorimetric method can be considered a promising alternative that is relatively less expensive and sufficiently reliable. In the current literature, no method for the analysis of nevirapine by spectro-fluorimetric has been reported. The proposed method is based on the transformation of naturally non-fluorescent nevirapine into a fluorescent derivative after chemical synthesis. Maximum excitation and emission wavelengths are 290 nm and 357 nm respectively. The analytical performance of the method demonstrates linearity in the concentration range 1.5 × 10<sup>-2</sup> and 13.5 × 10<sup>-2</sup> μg/mL with a correlation coefficient (r) greater than 0.999. The detection (LOD) and quantification (LOQ) limits found are 1.97 × 10<sup>-3</sup> μg/mL and 5.48 × 10<sup>-3</sup> μg/mL respectively. Recovery is achieved with 99.9% and 100.3% trueness, intra-day precision with a coefficient of variation of repeatability (CVr) of 0.99% and inter-day precision with a coefficient of variation of precision (CVR) of 1.7%. The method has been successfully applied in the analysis of 10 batches of nevirapine tablets and suspensions.展开更多
Highly sensitive spectrofluorimetric method was developed and validated for the determination of gabapentin in pure and pharmaceutical preparations. The method was based on nucleophilic substitution reaction of gabape...Highly sensitive spectrofluorimetric method was developed and validated for the determination of gabapentin in pure and pharmaceutical preparations. The method was based on nucleophilic substitution reaction of gabapentin with 4-fluoro-7-nitrobenzofurazan （NBD-F） in an alkaline medium （pH 9.5） to form a highly fluorescent derivative that was measured at 521 nm after excitation at 458 rim. The factors affecting the reaction was carefully studied and optimized. The method was successfully validated for linearity, limit of detection, limit of quantification, accuracy, precision, robustness and specificity. Under the optimized conditions, linear relationship with good correlation coefficient （0.9998） was found between the relative fluorescence intensity and gabapentin concentration in the range of 10--100 ng·mL^-1. The limit of detection and limit of quantification were 0.43 and 1.30 ng·mL ^-1, respectively. The proposed method was successfully applied to the determination of gabapentin in its pharmaceutical capsules. The results obtained by the proposed method were comparable with those obtained by the official method. Statistical comparison by t- and F- tests revealed that there was no significant difference between the results of the two methods with respect to mean values and standard deviations at the 95% confidence level.展开更多
A simple spectrofluorimetric method was developed for determination of trace amount of adenosine disodium triphosphate(ATP).Under the optimum conditions,we studied the interaction between CIP-Y3+-ATP complex by using ...A simple spectrofluorimetric method was developed for determination of trace amount of adenosine disodium triphosphate(ATP).Under the optimum conditions,we studied the interaction between CIP-Y3+-ATP complex by using absorption and fluorescence spectra.It was observed that ATP remarkably enhanced the fluorescence intensity of the CIP-Y3+ complex at λem=415 nm and the enhanced fluorescence intensity of Y3+ ion remained proportional to the concentration of ATP.The developed method was successfully applied for...展开更多
文摘A rapid,sensitive and simple spectrofluorimetric method was developed for the estimation of atorvastatin.In this method,the native fluorescence characteristics of atorvastatin have been studied in both acidic and basic media.High sensitivity was obtained with 5% acetic acid at 389 nm using 276 nm for excitation.Regression analysis showed a good correlation coefficient(r=0.9995) between fluorescence intensity and concentration over the range of 1.5-4 mg/mL with detection limit of 0.012 mg/mL.The proposed method was successfully applied to the analysis of atorvastatin in pure and pharmaceutical dosage forms with average recovery of 100.2970.47%.The results were compared favorably with those of the reported method.
文摘A spectrofluorimetric method for the determining riboflavin (VB2) based on its enhancement on the fluorescence of hemoglobin-catalyzed enzymatic reaction was proposed. The proposed method consisted of two reactions. One was the photochemical reaction of VB2, the other was a hemoglobin-catalyzed enzymatic reaction. The optimal experimental conditions for the determinations were established. The linear range of the method was 5.0×10?9?1.0×10?7 mol/L of VB2. The detection limit was calculated to be 3.65×10?9 mol/L. The relative standard deviation of this method was 2.3%at 7.0×10?2 mol/L for 11 determinations.
文摘Abstract: Terbium can form a stable binary chelate with terephthalic acid (benzene-1. 4-dicarboxylic acid(TPA) ) having a ratio of 1: 2 in aqueous solution in the pH range of 5～6. The maximum excitation and emission wavelengths are 260 nm and 545 nm for terbium chelate, respectively. The fluorescence intensity of terbium chelate remains stable in 8h with a relative standard deviation in the range of =4X. The rest of the lanthanide ions and the common foreign ions hardly interfere the determination.
基金The authors are gratelbl for financial supports IYom the National Natural Science roundation of Chinathe Educational Commiss
文摘A new spectrofluorimetric method for determination of trace terbium based on its reaction with 2.6-his-(1'-phenyl-3'-methyl-5'- pyridinediacyl (H_2PMBPP) and N- cetylpyridium bromide (CPB). at an apparent pH=5.0 provided by a hexamethylenetetramine (5% w/w)-hydrochloric acid buffer,is propesed. The calibration graph is linear in the ran ge from
文摘A highly sensitive and fairly selective spectrofluorimetric method has been developed for the determination of germanium with morin in tap water and health drink. The fluorescent reaction and optimal conditions of germanium with morin in phosphoric acid medium were studied. The detection limits of germanium in tap water and health drink were found to be 0.2 and 0.7μd/L respectively.
文摘The development of the spectrofluorimetric method can be considered a promising alternative that is relatively less expensive and sufficiently reliable. In the current literature, no method for the analysis of nevirapine by spectro-fluorimetric has been reported. The proposed method is based on the transformation of naturally non-fluorescent nevirapine into a fluorescent derivative after chemical synthesis. Maximum excitation and emission wavelengths are 290 nm and 357 nm respectively. The analytical performance of the method demonstrates linearity in the concentration range 1.5 × 10<sup>-2</sup> and 13.5 × 10<sup>-2</sup> μg/mL with a correlation coefficient (r) greater than 0.999. The detection (LOD) and quantification (LOQ) limits found are 1.97 × 10<sup>-3</sup> μg/mL and 5.48 × 10<sup>-3</sup> μg/mL respectively. Recovery is achieved with 99.9% and 100.3% trueness, intra-day precision with a coefficient of variation of repeatability (CVr) of 0.99% and inter-day precision with a coefficient of variation of precision (CVR) of 1.7%. The method has been successfully applied in the analysis of 10 batches of nevirapine tablets and suspensions.
文摘Highly sensitive spectrofluorimetric method was developed and validated for the determination of gabapentin in pure and pharmaceutical preparations. The method was based on nucleophilic substitution reaction of gabapentin with 4-fluoro-7-nitrobenzofurazan （NBD-F） in an alkaline medium （pH 9.5） to form a highly fluorescent derivative that was measured at 521 nm after excitation at 458 rim. The factors affecting the reaction was carefully studied and optimized. The method was successfully validated for linearity, limit of detection, limit of quantification, accuracy, precision, robustness and specificity. Under the optimized conditions, linear relationship with good correlation coefficient （0.9998） was found between the relative fluorescence intensity and gabapentin concentration in the range of 10--100 ng·mL^-1. The limit of detection and limit of quantification were 0.43 and 1.30 ng·mL ^-1, respectively. The proposed method was successfully applied to the determination of gabapentin in its pharmaceutical capsules. The results obtained by the proposed method were comparable with those obtained by the official method. Statistical comparison by t- and F- tests revealed that there was no significant difference between the results of the two methods with respect to mean values and standard deviations at the 95% confidence level.
基金supported by Department of Science & Technology (DST)University Grants Commission (UGC)[Project F.No.32-263/2006 (SR)],New Delhi under FIST and SAP
文摘A simple spectrofluorimetric method was developed for determination of trace amount of adenosine disodium triphosphate(ATP).Under the optimum conditions,we studied the interaction between CIP-Y3+-ATP complex by using absorption and fluorescence spectra.It was observed that ATP remarkably enhanced the fluorescence intensity of the CIP-Y3+ complex at λem=415 nm and the enhanced fluorescence intensity of Y3+ ion remained proportional to the concentration of ATP.The developed method was successfully applied for...
