Determination of boron in water samples by dispersive liquid–liquid microextraction based on the solidification of a floating organic drop coupled with a fluorimetric method

Abstract

In this work, a new, rapid and reliable method for the determination of boron in water samples by dispersive liquid-liquid microextraction based on the solidification of a floating organic drop (DLLME-SFO) prior to fluorescence spectra analysis was developed. As a result of its complexation with boric acid, the method relies on the enhancement of the fluorescence (λex = 350 nm, λem = 373 nm) of chromotropic acid. The influences of DLLME-SFO parameters, including the extraction solvent type and its volume, pH, the disperser solvent type and its volume, and salt effects were investigated. Under the optimized conditions, the limit of detection was 0.11 ng L(-1), with a preconcentration factor of 86 times. The calibration curve was linear in the range of 0-40 nM. The proposed method has also been successfully applied to analyze real water samples and the relative recoveries of water samples ranged from 86.9 to 93.2%.

Decay-Associated Fluorescence for Boron Determination in Uranium-Based Nuclear Fuels

“…Among the two types of complexes formed, the 1:2 complex provides larger sensitivity. ,,, Thus, experimental conditions (pH 5 by sodium acetate buffer and large excess of ligand) were tuned to form the 1:2 complex exclusively. Formation of the 1:2 complex under these conditions has been experimentally corroborated by job plots, pH, and ESI-Q-TOF MS experiments and has been reported . The structures of the chromotropic acid and 1:2 complex are given in Chart .…”

A twin enrichment method based on dispersive liquid–liquid microextraction and field-amplified sample injection for the simultaneous determination of sulfonamides

“…Among them, DLLME is an ideal technique because of its simplicity, low cost, effectiveness, speed, and the small consumption of organic solvents. [12][13][14][15][16][17][18][19] Moreover, compared with SPE based approaches which require tedious adsorbents preparation steps, DLLME can run quickly in general laboratory by only routine glassware and a few microliters of organic solvents. It is well known that the figures of merits of analytical approaches are extremely dependent on their corresponding enrichment efficiencies.…”

A critical review on the determination of boron in various matrices

“…Some fluorescent boron complexes have been obtained and used for fluorimetric boron determination [11]. However, in the period of 2015 -2018 only one article was published about fluorimetric method [8]. The published papers on boron determination by molecular spectrometric methods in this period were discussed and some analytical parameters are summarized in Table 3.…”

“…There is a narrow margin between useful and harmful concentrations. Boron is necessary to provide the cell membrane function, enzymatic reactions [8] and the utilization of calcium for the human bone structure [9]. When given boric acid or borax to rats, mice and dogs by food or drinking-water, testicular lesions have been observed and no increase in tumor incidence observed in long-term studies [6].…”