UV-assisted Fenton digestion of rice for the determination of trace cadmium by hydride generation atomic fluorescence spectrometry

Abstract

A new digestion method using UV-assisted Fe(0) Fenton reaction was developed for the determination of trace Cd in rice by hydride generation atomic fluorescence spectrometry. The proposed method integrated the advantages of simplicity, small dose of reagents, low cost and moderate reaction conditions, and was successfully utilized to analyze a Certified Reference Material (CRM) and real rice samples. A 1 mL mixture of the sample and reagents (0.0500 g rice powder, 0.2% (m/v) Fe(0), 0.75% (v/v) HNO3 and 18% (v/v) H2O2) was irradiated by UV-light for 50 min and then a clear solution was obtained by separating excess Fe(0) with a magnet prior to spectral analysis. The limit of detection (LOD) for Cd was found to be 0.02 mg kg(-1) and the relative standard deviation was better than 5.0% at a concentration level of 0.40 mg kg(-1). The recovery obtained by analyzing the CRM was 103% and spiked recoveries with 0.40 mg kg(-1) Cd in rice samples were 93% and 101%. The t-test proved that there is no significant difference between the certified value and the determined value of the CRM, and between the proposed method and microwave-assisted digestion coupled with inductively coupled plasma mass spectrometry (MWD-ICP-MS) at 95% confidence level.

Low-Temperature and Atmospheric Pressure Sample Digestion Using Dielectric Barrier Discharge

“…Unfortunately, COD could not be applied to indicate the digestion efficiency of sample obtained using H 2 O 2 -DBD-digestion and HNO 3 -DBD-digestion systems because Cr 2 O 7 2– not only oxidizes organic compounds but also oxidizes inorganic reducing substances under these conditions. In the H 2 O 2 -DBD-digestion system, the residual H 2 O 2 could react with Cr 2 O 7 2– , which would lead to interferences of reaction between organic matters and Cr 2 O 7 . − …”

“…Advanced oxidation processes (AOPs) based on UV irradiation with/without photocatalysts and oxidizing reagents, ozone in the presence/absence of UV or ultrasound irradiation, UV photocatalysis, or Fenton reaction, which involves in situ generation of highly potent chemical oxidizing species (hydroxyl radical, ·OH etc. ), have been regarded as efficient techniques for the decomposition of organic pollutants in wastewater and as a promising alternative to the conventional sample digestion techniques for the determination of trace elements by atomic spectrometry. − Various Fenton-like catalysts were used to improve the digestion capabilities of AOPs, including Fe 0 and Fe 3 O 4 nanomaterials. These materials remarkably accelerate the generation of oxidizing radicals from H 2 O 2 , significantly improving the digestion performance of AOPs.…”

Quantification of Cadmium in Rice by Surface-enhanced Raman Spectroscopy Based on a Ratiometric Indicator and Conical Holed Enhancing Substrates

“…2 Therefore, the quantitative monitoring of Cd 2+ in rice is of vital importance to people's health. Various analytical techniques, including immunochromatography, 3 inductively coupled plasma mass spectrometry (ICP-MS), 4 atomic absorption spectrometry (AAS), 5,6 atomic fluorescence spectrometry (AFS) 7 and colorimetric method 2 have been applied to the detection of Cd 2+ . However, the applications of AAS, AFS and ICP-MS involve large-sized instruments that are only suitable for off-line analysis.…”

An Ultrasensitive Colorimetric Strategy for Detection of Cadmium Based on the Peroxidase-like Activity of G-Quadruplex-Cd(II) Specific Aptamer

“…The efficient analytical techniques for determination of Cd have been widely reported, such as atomic fluorescence spectrometry (AFS), [11][12][13] inductively coupled plasma mass spectrometry (ICP-MS), 14,15 atomic absorption spectroscopy (CVG-AAS) [16][17][18] and high performance liquid chromatography. 19 Although the above mentioned techniques are accurate and efficient, many of them either require costly equipment or skilled operators.…”