Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8954894 | Microchemical Journal | 2019 | 25 Pages |
Abstract
Laser-induced breakdown spectroscopy (LIBS) is a multi-elemental technique with multiple advantages. However, direct determination in liquid samples is not an easy task since laser water interaction can affect the precision and accuracy of the method and cause loss of sensitivity. To enable LIBS application in liquid sample analysis, some strategies such as liquid-to-solid transfer have been used. This work proposes the quantification of chromium in water samples by LIBS using ceramic as the solid support. Results showed that the ceramic selectively adsorbs Cr(III) species at pHâ¯7 and quantification of Cr(VI) species by LIBS was also possible after reduction of this species to Cr(III) using Fe(II) as the reducing agent. Instrumental parameters were optimized, and the best conditions found included a 65â¯Î¼m spot size, 430 accumulated pulses with 20â¯mJâ¯pulseâ1, and 0.75â¯ms of delay time. Calibration was carried out with synthetic calibration standards prepared by adsorption of increasing concentrations of chromium in ceramic. Tap water samples spiked with 0.9â¯mgâ¯Lâ1 of Cr(III) and 0.1â¯mgâ¯Lâ1 of Cr(VI) were analysed by the proposed method and recoveries of 105â¯Â±â¯2% and 103â¯Â±â¯3% were obtained for Cr(III) and Cr(VI), respectively.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Alexandrina A.C. Carvalho, Daniel M. Silvestre, Flávio O. Leme, Juliana Naozuka, Danielle P. Intima, Cassiana S. Nomura,