Development of a continuous flow hydride generation laser-induced breakdown spectroscopic system: Determination of tin in aqueous environments

Abstract

The design, construction and optimization studies of a continuous flow hydride generation laser-induced breakdown spectroscopic system, HG-LIBS, for the determination of tin in aqueous environments is presented. Optimization of the Laser Induced Breakdown Spectroscopy (LIBS) signal with respect to carrier gas flow rate, analyte, acid (HCl) and reductant (NaBH 4 ) concentrations and flow rates was performed by using spectral emission intensity from the neutral Sn(I) line at 284.0 nm under atmospheric pressures. With flow rates of 5.0 mL/min for NaBH 4 and 2.5 mL/min for HCl, optimum NaBH 4 and HCl concentrations were determined as 2.0% (w/v) and 1.0% (v/v), respectively. The hydride generation efficiency of the system was tested for tin hydride, stannane (SnH 4 ), by inductively coupled plasma mass spectrometer (ICP-MS). It was found that higher than 99% of the analyte was released into the gaseous phase. Upon optimization, the minimum detectable Sn concentration was found as 0.3 mg/L in water samples. That corresponds to more than two orders of increase in sensitivity compared to methods that employ common sample introduction techniques in liquids analysis by LIBS. Over 90% recoveries were obtained from spiking experiments with river, tap and drinking water samples. Results illustrate potential use of the continuous flow HG-LIBS system for monitoring of Sn concentrations in aqueous environments.

Optimization of chemical and instrumental parameters in hydride generation laser-induced breakdown spectrometry for the determination of arsenic, antimony, lead and germanium in aqueous samples

“…Detection limits obtained for As, and Sb in this study are comparable with the ones in literature [26,28] To the best of our knowledge, there is no record in the literature based on HG-LIBS detection of Pb and Ge, however, there are several reports on the determination of Pb in aqueous solutions based on direct liquids analysis by LIBS. Detection limits of 40 mg L −1 [6], and 100 mg L −1 Pb [14] were reported for experiments on liquid-jet and in bulk water analysis, respectively.…”

“…The experimental set-up for continuous flow hydride generation LIBS system [28], consists of a hydride generation, plasma formation and detection units.…”

“…Recently, analysis of liquids based on hydride generation sample introduction technique with laser-induced breakdown spectroscopic detection, HG-LIBS, for some of the hydride forming elements have been shown [27][28][29].…”

“…In our previous work [28], development of a hydride generation laser-induced breakdown spectroscopic technique, HG-LIBS, in continuous flow mode was realized. The chemical and instrumental parameters of the system were systematically studied in order to achieve optimal conditions for the determination of tin (Sn) in aqueous environments.…”

Development and validation of a laser-induced breakdown spectroscopic method for ultra-trace determination of Cu, Mn, Cd and Pb metals in aqueous droplets after drying

“…Plasma formation on flowing jet liquids [3][4][5], inside bubbles [6], on liquid droplets [7][8], on aerosols formed by nebulization [9,10] or by electro-spray ionization [11,12], on samples in which physical conditions are changed by freezing [13,14] or by chemical derivatization [15][16][17][18], liquids adsorbed on solid substrates [19][20][21][22][23] or on sol-gels [24] and use of sequential laser pulses [25][26][27][28][29] are some of the efforts devoted in the last decade to increase the analytical capability of the LIBS technique for liquids analysis. Also, filtration based approaches, collection of the suspended particles like pollen, bacteria, fungi and viruses on filters enabled analysis of biological materials in water [30].…”