Rapid determination of trace cadmium in drinking water using laser-induced breakdown spectroscopy coupled with chelating resin enrichment

Abstract

The determination of heavy metals in drinking water is of great importance, but it is hard to realize rapid and in-situ measurement. Laser-induced breakdown spectroscopy is an effective method for both solid and liquid sample analysis with advantages of fast and micro-destructive. However, the concentrations of heavy metals in drinking water is too low to be directly detected using LIBS. In this study, we enhanced the sensitivity of LIBS by coupling with chelating resin, which is usually used for water purification. The resin provided a rapid enrichment of the heavy metal, so the limits of detection of common LIBS system was much enhanced. Using Cadmium as the representative heavy metal, PLSR model for predicting Cd were built based on the spectral intensity (Cd 214.4 nm) with concentrations from 0 to 100 µg/L, and resulted in correlation coefficient of 0.94433 and RMSE of 7.1517 µg/L. The LoD was 3.6 µg/L. Furthermore, the volume, resin mass, adsorption time, and LIBS system parameters were optimized for practical applications. We also demonstrated that the resin can be recycled without loss in sensing ability. The combination of chelating resin with LIBS provides inexpensive, rapid, and sensitive detection method of trace heavy metal contaminants in drinking water.

An Integrating Platform of Ratiometric Fluorescent Adsorbent for Unconventional Real-Time Removing and Monitoring of Copper Ions

“…With the enormously increased anthropogenic discharge, heavy metal contaminants have been the prominent contributor to wastewater, which has been a great threat to life on earth over the past several decades. , Among the toxic heavy metal ions, the treatment of copper is of special concern because of its recalcitrance and persistence in the environment, which also creates permanent damage to the ecosystem structure and human beings through the food chain. − For the time being, a range of functional materials including membranes, nanoparticles, , hydrogels, , and metal–organic framework (MOF) materials , have been developed as hybrid composites to mitigate water pollution, e.g., QN-PAEK/rGO composite membrane, Fe 3 O 4 /carboxylate graphene oxide, PVA/PAA/GO–COOH@PDA, P-CD/adamantane-modified (PAA-Ad), AuNP/T-G composite, SrTiO 3 @MoS 2 , Ag/TiO 2 /g-C 3 N 4 , amyloid fibrils-ZrO 2 hybrid membranes, polydopamine microspheres, and Zr/Mg oxide-PS . Although these materials have good performances for heavy-metal-ion adsorption or detection, the utilization of these conventional materials in related analytical techniques is likely to be shadowed on account of these nonintelligent materials being for removal or detection purposes only and many of them lack specific recognition toward analytes, which may not be suitable for quantitative analysis applications in water decontamination and monitoring.…”

“…W ith the enormously increased anthropogenic discharge, heavy metal contaminants have been the prominent contributor to wastewater, which has been a great threat to life on earth over the past several decades. 1,2 Among the toxic heavy metal ions, the treatment of copper is of special concern because of its recalcitrance and persistence in the environment, 3 which also creates permanent damage to the ecosystem structure and human beings through the food chain. 4−6 For the time being, a range of functional materials including membranes, 7 nanoparticles, 8,9 hydrogels, 10,11 and metal− organic framework (MOF) materials 12,13 have been developed as hybrid composites to mitigate water pollution, e.g., QN-PAEK/rGO composite membrane, 14 Fe 3 O 4 /carboxylate graphene oxide, 15 PVA/PAA/GO−COOH@PDA, 16 P-CD/adamantane-modified (PAA-Ad), 17 AuNP/T-G composite, 18 SrTiO 3 @MoS 2 , 19 Ag/TiO 2 /g-C 3 N 4 , 20 amyloid fibrils-ZrO 2 hybrid membranes, 21 polydopamine microspheres, 22 and Zr/ Mg oxide-PS.…”

Preparation and Characterization of a Novel Amidoxime-Modified Polyacrylonitrile/Fly Ash Composite Adsorbent and Its Application to Metal Wastewater Treatment

“…The adsorption data were fitted by the pseudo-first order kinetic model (Equation (1)) [ 47 ], pseudo-second order kinetic model (Equation (2)) [ 48 ], and the Elovich equation (Equation (3)) [ 49 ], respectively. where q e and q t (mg/g) are the amount of adsorbate adsorbed at equilibrium and at any time t (min), respectively; k 1 and k 2 are the pseudo-first order kinetic adsorption rate constant (min −1 ) and the pseudo-second order kinetic adsorption rate constant [g/(min·mg)], respectively; t is the adsorption time (min); and α and β are the parameters of the adsorption kinetic model.…”

Application of Laser-Induced Breakdown Spectroscopy and Chemometrics for the Quality Evaluation of Foods with Medicinal Properties: A Review

“…In recent years, ML has made significant advances beyond the traditional chemometric method [ 15 ]. It now provides robust and continuously updated algorithms and tools for developing spectroscopic data treatment models [ 16 , 17 ]. RF, for example [ 18 ], SVM [ 19 ], etc., have been utilized widely in quantitative and qualitative LIBS spectral analyses.…”