Determination of bismuth in different samples by dispersive liquid-liquid microextraction coupled with microvolume β-correction spectrophotometry (Article)
A novel microvolume β-correction spectrophotometric method was proposed for the sensitive and selective determination of bismuth coupling with dispersive liquid-liquid microextraction (DLLME). The basis of the method is a quantitative colorimetric reaction between Bi3 + ions and dithizone, and the orange-brown colored complex of Bi(HDz)3 was then extracted into CCl4 phase by DLLME. Parameters related to the efficiency of microextraction, such as pH, complexant concentration, the volume ratio of disperser solvent and extraction solvent were discussed and optimized in detail. Under the optimized conditions, the real absorbance was in proportion to bismuth concentration in the range of 3-100 μg·L- 1 with a correlation coefficient (R) of 0.993. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.54 μg·L- 1 and 1.80 μg·L- 1, respectively. Good recoveries of bismuth were obtained in the range of 96.3-103.6% in different real samples confirming the accuracy of developed procedure and its independence from matrix interference.