A novel biostructure sorbent based on CysSB/MetSB@MWCNTs for separation of nickel and cobalt in biological samples by ultrasound assisted-dispersive ionic liquid-suspension solid phase micro extraction

Rapid extraction of BTEX in water and milk samples based on functionalized multi-walled carbon nanotubes by dispersive homogenized-micro-solid phase extraction

An advanced synthesis based on the phenylalanine (Phe) and task-specific ionic liquid (TSIL) functionalized on multi-walled carbon nanotubes (Phe/TSIL@MWCNTs), was used to extract benzene, ethylbenzene, toluene, and xylene (BTEX) from cow's milk, powdered milk, and farm water samples. The BTEX was efficiently extracted by ultrasound-assisted dispersive homogenized-micro-solid phase extraction (USA-DH-µ-SPE) between 95.1% and 103.4%. By procedure, 50 mg of Phe/TSIL@MWCNTs was added to 0.2 mL of acetone and injected into 10 mL of the samples. The upper aqueous solution was vacuumed, the vial heated to 80 °C, and the BTEX desorbed in the vial. Then, using a Hamilton syringe, 1-20 µL of gas in the headspace vial was determined by injecting it into the gas chromatography with flame ionization detection (GC-FID). The linear range, LOD, and LOQ for BTEX in milk and water samples were obtained at 0.05-500 µg L^-1, 15 ng L^-1, and 50 ng L^-1, respectively (r = 0.9997, RSD% = 2.27).

Green bioanalysis: an innovative and eco-friendly approach for analyzing drugs in biological matrices

Green bioanalytical techniques aim to reduce or eliminate the hazardous waste produced by bioanalytical technologies. A well-organized and practical approach towards bioanalytical method development has an enormous contribution to the green analysis. The selection of the appropriate sample extraction process, organic mobile phase components and separation technique makes the bioanalytical method green. UHPLC-MS is the best option, whereas supercritical fluid chromatography is one of the most effective green bioanalytical procedures. Nevertheless, there remains excellent scope for further research on green bioanalytical methods. This review details the various sample preparation techniques that follow green analytical chemistry principles. Furthermore, it presents green solvents as a replacement for conventional organic solvents and highlights the strategies to convert modern analytical techniques to green methods.

Aramid-wrapped CNT hybrid sol–gel sorbent for polycyclic aromatic hydrocarbons

This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network.

Role of Ionic Liquids in Composites in Analytical Sample Preparation

Ionic liquids (ILs) are a group of non-conventional salts with melting points below 100 °C. Apart from their negligible vapor pressure at room temperature, high thermal stability, and impressive solvation properties, ILs are characterized by their tunability. Given such nearly infinite combinations of cations and anions, and the easy modification of their structures, ILs with specific properties can be synthesized. These characteristics have attracted attention regarding their use as extraction phases in analytical sample preparation methods, particularly in liquid-phase extraction methods. Given the liquid nature of most common ILs, their incorporation in analytical sample preparation methods using solid sorbents requires the preparation of solid derivatives, such as polymeric ILs, or the combination of ILs with other materials to prepare solid IL-based composites. In this sense, many solid composites based on ILs have been prepared with improved features, including magnetic particles, carbonaceous materials, polymers, silica materials, and metal-organic frameworks, as additional materials forming the composites. This review aims to give an overview on the preparation and applications of IL-based composites in analytical sample preparation in the period 2017–2020, paying attention to the role of the IL material in those composites to understand the effect of the individual components in the sorbent.