Roles of inorganic oxide nanoparticles on extraction efficiency of electrospun polyethylene terephthalate nanocomposite as an unbreakable fiber coating

Adsorbents obtained from recycled polymeric materials for retention of different pollutants: A review

Polymeric waste is an environmental problem, with an annual world production of approximately 368 million metric tons, and increasing every year. Therefore, different strategies for polymer waste treatment have been developed, and the most common are (1) redesign, (2) reusing and (3) recycling. The latter strategy represents a useful option to generate new materials. This work reviews the emerging trends in the development of adsorbent materials obtained from polymer wastes. Adsorbents are used in filtration systems or in extraction techniques for the removal of contaminants such as heavy metals, dyes, polycyclic aromatic hydrocarbons and other organic compounds from air, biological and water samples. The methods used to obtain different adsorbents are detailed, as well as the interaction mechanisms with the compounds of interest (contaminants). The adsorbents obtained are an alternative to recycle polymeric and they are competitive with other materials applied in the removal and extraction of contaminants.

Recent Applications and Newly Developed Strategies of Solid-Phase Microextraction in Contaminant Analysis: Through the Environment to Humans

The present review aims to describe the recent and most impactful applications in pollutant analysis using solid-phase microextraction (SPME) technology in environmental, food, and bio-clinical analysis. The covered papers were published in the last 5 years (2014–2019) thus providing the reader with information about the current state-of-the-art and the future potential directions of the research in pollutant monitoring using SPME. To this end, we revised the studies focused on the investigation of persistent organic pollutants (POPs), pesticides, and emerging pollutants (EPs) including personal care products (PPCPs), in different environmental, food, and bio-clinical matrices. We especially emphasized the role that SPME is having in contaminant surveys following the path that goes from the environment to humans passing through the food web. Besides, this review covers the last technological developments encompassing the use of novel extraction coatings (e.g., metal-organic frameworks, covalent organic frameworks, PDMS-overcoated fiber), geometries (e.g., Arrow-SPME, multiple monolithic fiber-SPME), approaches (e.g., vacuum and cold fiber SPME), and on-site devices. The applications of SPME hyphenated with ambient mass spectrometry have also been described.

A new strategy for electrochemical fabrication of manganese dioxide coatings based on silica nanoparticles deposited on titanium fibers for selective and highly efficient solid-phase microextraction

Electrochemical fabrication of a novel Ti@TiO₂@SiO₂NPs@MnO₂/PPyNPs fiber and its application in solid-phase microextraction coupled to HPLC-UV.

Carbon Nanohorn Suprastructures on a Paper Support as a Sorptive Phase

This article describes a method for the modification of paper with single-wall carbon nanohorns (SWCNHs) to form stable suprastructures. The SWCNHs form stable dahlia-like aggregates in solution that are then self-assembled into superior structures if the solvent is evaporated. Dipping paper sections into a dispersion of SWCNHs leads to the formation of a thin film that can be used for microextraction purposes. The coated paper can be easily handled with a simple pipette tip, paving the way for disposable extraction units. As a proof of concept, the extraction of antidepressants from urine and their determination by direct infusion mass spectrometry is studied. Limits of detection (LODs) were 10 ng/L for desipramine, amitriptyline, and mianserin, while the precision, expressed as a relative standard deviation, was 7.2%, 7.3%, and 9.8%, respectively.

Electrospun polycaprolactam-manganese oxide fiber for headspace-solid phase microextraction of phthalate esters in water samples

The nanofibrous polycaprolactam (polyamide 6 (PA6)) incorporated with manganese oxide (MnO) nanoparticles was fabricated by electrospinning and used as a new fiber coating for headspace-solid phase microextraction (HS-SPME) of the selected phthalate esters (PEs) in water samples prior to GC-μECD. The adsorbent was fully characterized using scanning electron microscopy (SEM), Fourier transform-infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA). The main parameters that affect the HS-SPME efficiency such as extraction temperature, ionic strength, extraction and desorption times were investigated. The analytical figures of merit were obtained under the optimized conditions as follows: linear dynamic range (LDR), 0.500-5.00 × 10² ng mL^-1; relative standard deviations (RSDs, n = 3), 1.86-10.9%; limits of detection (LODs), 0.0400-0.193 ng mL^-1. The method was applied for determination of the target analytes in river water, bottled water, mineral water and soda samples and the relative recoveries were obtained between 90.3 and 107%.

Application of nanocomposite-based sorbents in microextraction techniques: a review

This review provides a general overview of the recent trends for the preparation of nanocomposites and their applications in microextraction techniques.

Silica nanoparticles–nylon 6 composites: synthesis, characterization and potential use as sorbent

Silica nanoparticle–nylon 6 composites are successfully synthesized following a simple and rapid procedure. After their characterization, the composites were evaluated as sorbents under a dispersive solid phase microextraction format.

Dispersive graphene-based silica coated magnetic nanoparticles as a new adsorbent for preconcentration of chlorinated pesticides from environmental water

The present study describes the synthesis, characterization and application of new graphene-based silica coated magnetic nanoparticles (Fe₃O₄@SiO₂–G) for the simultaneous preconcentration of four chlorinated pesticides from contaminated water.