An automatic, vigorous-injection assisted dispersive liquid–liquid microextraction technique for stopped-flow spectrophotometric detection of boron

Abstract A novel automatic vigorous-injection assisted dispersive liquid–liquid microextraction procedure based on the use of a modified single-valve sequential injection manifold (SV-SIA) was developed and applied for determination of boron in water samples. The major novelties in the procedure are the achieving of efficient dispersive liquid–liquid microextraction by means of single vigorous-injection (250 µL, 900 µL s −1 ) of the extraction solvent ( n -amylacetate) into aqueous phase resulting in the effective dispersive mixing without using dispersive solvent and after self-separation of the phases, as well as forwarding of the extraction phase directly to a Z-flow cell (10 mm) without the use of a holding coil for stopped-flow spectrophotometric detection. The calibration working range was linear up to 2.43 mg L −1 of boron at 426 nm wavelength. The limit of detection, calculated as 3 s of a blank test ( n =10), was found to be 0.003 mg L −1 , and the relative standard deviation, measured as ten replicable concentrations at 0.41 mg L −1 of boron was determined to be 5.6%. The validation of the method was tested using certified reference material.