Sensitive kinetic-catalytic spectrophotometric method for cobalt determination using a chip coupled to a multisyringe flow injection analysis system
| Autor: | Fatima Zohra Abouhiat, Farida El Yousfi, Víctor Cerdà, Camelia Henríquez |
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| Rok vydání: | 2017 |
| Předmět: |
Flow injection analysis
Detection limit Hydroxybenzoic acid Chromatography Chemistry 010401 analytical chemistry Analytical chemistry chemistry.chemical_element 02 engineering and technology Pharmaceutical formulation 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Analytical Chemistry Volumetric flow rate Catalysis Reagent 0210 nano-technology Cobalt |
| Zdroj: | Talanta. 166:405-411 |
| ISSN: | 0039-9140 |
| DOI: | 10.1016/j.talanta.2015.12.005 |
| Popis: | The development of an automated kinetic-catalytic spectrophotometric method for cobalt determination is presented. The method is based on the catalytic effect of Co in the oxidation of hydroxybenzoic acid by H2O2 in basic media. The method has been automated using a multisyringe flow injection system coupled to a monolithic flow conduit called chip (chip-MSFIA). All reagents and sample are simultaneously propelled into the chip to achieve an efficient mixing. The reaction product is monitored at 482 nm. The reaction takes place very fast at room temperature, thus the fixed-time method is applied to quantify Co concentration in samples. Variables such as, reagents concentration, pH, flow rate and reaction time have been optimized to improve the selectivity and sensitivity of the proposed system. Under optimal conditions, Co may be determined in the range 0.02–10.00 μg L−1 achieving a limit of detection of 0.02 μg L−1 and an injection throughput of 68 h−1. Relative standard deviations are below 3%. The method has been successfully applied to water samples and a pharmaceutical formulation. The accuracy of the method has been validated by add-recovery tests and satisfactory recoveries from 91% to 97% were obtained. |
| Databáze: | OpenAIRE |
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