New modified carbon based solid phase extraction sorbent prepared from wild cherry stone as natural raw material for the pre-concentration and determination of trace amounts of copper in food samples

Qualitative identification of volatile compounds in foods and flowers using passive headspace extraction with activated charcoal fabric

This study investigates the application of passive headspace analysis to several different foods and flowers and compares these results to other published studies. The method demonstrates the applicability of passive headspace analysis for extraction and qualitative analysis of volatile flavor components of citrus fruits and flower blossoms. The method is simple, inexpensive, fast, and provides an alternative to analysis of volatile flavor and fragrance compounds using solid phase microextraction techniques and other extraction techniques.

Development of dispersive solid-phase microextraction coupled with high-pressure liquid chromatography for the preconcentration and determination of the selected neonicotinoid insecticides

Neonicotinoid insecticides have raised a lot of societal concerns due to their environmental ubiquity and unique mode of action. Therefore, it is of great research interest to monitor their occurrence in the environmental waters. However, these compounds exist at low concentrations that is below instrument detection limits. This study reports the applicability of magnetic poly (3 aminobenzoic acid)-based activated carbon (Fe3O4@PABA/AC) composite as an adsorbent in dispersive magnetic solid-phase microextraction (d-MSPME) of neonicotinoid insecticides from wastewater and river water samples. The as-synthesized adsorbent was characterized and confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller and X-ray diffraction spectroscopy. The analytes of interest were detected and quantified by high-performance liquid chromatography coupled with diode array detector (HPLC–DAD). The parameters affecting the extraction and preconcentration processes, such as pH, extraction time, mass of adsorbent, desorption time and eluent volume, were optimized using fractional factorial design and central composite design. Under optimum conditions, the limits of detection and quantification were in the ranges of 0.41–0.82 µg L−1 and 1.4–2.7 µg L−1, respectively. The linearity ranged from 1.4–700 µg L−1 with correlation of determination (R2) values varied between 0.9933 and 0.9987. The intra-day and inter-day precisions were 0.35–0.75% and 1.7–5.5%, respectively. The spike recovery experiments were conducted to evaluate the accuracy of the d-MSPME analytical method in real samples, and the percentage recoveries ranged from 86.7 to 99.2%. Therefore, this method shows great potential applicability in preconcentrating the pollutants from the environment.

Preparation of polyacrylonitrile/polyindole conducting polymer composite and its use for solid phase extraction of copper in a certified reference material

A polyacrylonitrile/polyindole (PAN/PIN) [50, 50] conducting polymer composite was chemically synthesized using FeCl₃ as an oxidizing agent in chloroform solution and nitrogen atmosphere at 10 °C. The formation of the composite was supported by Fourier transform infrared spectroscopy. The morphological properties of the composite were investigated by atomic force microscopy and scanning electron microscopy. The thermal properties of the composite were examined by using thermogravimetric analyses. It was found that the composite had good thermal stability. The conducting polymer composite was used for the first time as an adsorbent for solid phase extraction of Cu (II). The optimum pH was found to be 7. The adsorption and elution shaking times were 5 and 15 min, respectively. The elution was done with 5 mL of 2 mol L^-1 HNO₃. The accuracy of the developed method was confirmed by analyzing certified reference material (TMDA-70.2 Lake Water).

Recent Materials Developed for Dispersive Solid Phase Extraction

Solid phase extraction (SPE) is an analytical procedure developed with the purpose of separating a target analyte from a complex sample matrix prior to quantitative or qualitative determination. The purpose of such treatment is twofold: elimination of matrix constituents that could interfere with the detection process or even damage analytical equipment as well as enriching the analyte in the sample so that it is readily available for detection. Dispersive solid phase extraction (dSPE) is a recent development of the standard SPE technique that is attracting growing attention due to its remarkable simplicity, short extraction time and low requirement for solvent expenditure, accompanied by high effectiveness and wide applicability. This review aims to thoroughly survey recently conducted analytical studies focusing on methods utilizing novel, interesting nanomaterials as dSPE sorbents, as well as known materials that have been only recently successfully applied in dSPE techniques, and evaluate their performance and suitability based on comparison with previously reported analytical procedures.

Evolution of Environmentally Friendly Strategies for Metal Extraction

The demand for the recovery of valuable metals and the need to understand the impact of heavy metals in the environment on human and aquatic life has led to the development of new methods for the extraction, recovery, and analysis of metal ions. With special emphasis on environmentally friendly approaches, efforts have been made to consider strategies that minimize the use of organic solvents, apply micromethodology, limit waste, reduce costs, are safe, and utilize benign or reusable materials. This review discusses recent developments in liquid- and solid-phase extraction techniques. Liquid-based methods include advances in the application of aqueous two- and three-phase systems, liquid membranes, and cloud point extraction. Recent progress in exploiting new sorbent materials for solid-phase extraction (SPE), solid-phase microextraction (SPME), and bulk extractions will also be discussed.