Determination of cadmium in bread and biscuit samples using ultrasound‐assisted temperature‐controlled ionic liquid microextraction

Abstract

BACKGROUND In the present work, a simple and rapid method was proposed for the preconcentration of cadmium using ultrasound‐assisted temperature‐controlled ionic liquid microextraction (TC‐IL‐LPME). The dispersion of the ionic liquid (1‐Hmim[PF6]) in the aqueous phase was performed by heating it in an ultrasonic bath, followed by cooling in an ice bath. After centrifugation, the enriched phase was dissolved in 45% (w/w) nitric acid solution to reduce viscosity, and the cadmium content was measured employing electrothermal atomic absorption spectrometry (ET‐AAS). The 2‐(5‐bromo‐2‐pyridylazo)‐5‐diethylaminophenol reagent (Br‐PADAP) was used as a complexing agent. RESULTS Under optimized conditions, the method had a detection limit of 2.0 ng L−1 and an enrichment factor of 24. The accuracy of the method was evaluated through the analysis of the certified reference material of brown bread (BCR‐191). The method was applied to the determination of cadmium in samples of bread and biscuit. The limit of detection of the solid samples was 0.10 μg kg−1. The recovery of cadmium in the samples varied between 93% and 107%. CONCLUSION The proposed method is presented as a simple, cheap, ecological and a sensitive alternative for the determination of cadmium in bread and biscuit samples. © 2019 Society of Chemical Industry

Biscuit Contaminants, Their Sources and Mitigation Strategies: A Review

“…The safety characteristics of raw materials in terms of heavy metals are ruled by current legislation and rely on continuous analytical monitoring. Recently, a cheap, rapid, and ecological method was proposed for the preconcentration of cadmium in biscuit samples by using ultrasound-assisted temperature-controlled ionic liquid microextraction (TC-IL-LPME), making analyses easier [42].…”

A comparative study of different methods for the determination of cadmium in various tissues of ramie (Boehmeria nivea L.)

“…Determination of Cd in fish by atomic absorption spectrometry with electrothermal atomization is based on sample digestion in a microwave oven and subsequently read using an atomic absorption spectrometer with a graphite furnace (Costa et al, 2012 ). Determination of Cd in bread and biscuit samples using ultrasound-assisted temperature-controlled ionic liquid microextraction is presented as a simple, cheap, ecological, and sensitive alternative (Santos et al, 2019 ). An all-solid light addressable potentiometric sensor (LAPS) is presented for determination of Cd in rice, which is satisfactory precision, accuracy, and selectivity (Zhang et al, 2018 ).…”

Determination of Ferulic Acid in Angelica sinensis by Temperature-Controlled Hydrophobic Ionic Liquids-Based Ultrasound/Heating-Assisted Extraction Coupled with High Performance Liquid Chromatography

“…Recently, ionic liquids (ILs) have become promising alternatives to the traditional organic solvents employed in sample preparation because of their unique properties, such as negligible vapor pressure, high thermal stability, non-flammability and good solubility for many inorganic and organic compounds [17]. Therefore, ILs have been extensively applied as substituents for conventional organic solvents in various extraction processes including salt-induced liquid-liquid extraction (SI-LLE) [18], dispersive liquid-phase microextraction (DLPME) [19], microwave-assisted extraction (MAE) [20], pressurized liquid extraction [21], ultrasonic-assisted extraction [22][23][24] and temperature-controlled liquid phase micro-extraction (TC-LPME) [25][26][27][28]. In this context, hydrophobic ILs are usually used to extract liquid samples, while hydrophilic ILs are mostly used to extract solid samples.…”

“…Due to the high viscosity of hydrophobic ILs and the difficulty of phase separation, it is rarely reported that hydrophobic ILs were directly used to extract solid samples [29]. In most cases, water and organic solvent were firstly used to extract the trace components in solid samples, and then hydrophobic ILs were selected to extract and concentrate the trace components in the extracts [25]. This process was not only complicated and time-consuming, but also easy to cause measurement errors.…”