Nanostructure conducting molecularly imprinted polypyrrole film as a selective sorbent for benzoate ion and its application in spectrophotometric analysis of beverage samples

Oxoanion complexation of nitroisophthalamide receptors: Insights from the DFT calculations

Amide derivative receptors have been designed to investigate the oxoanion complexation ability via hydrogen and halogen bond interactions. Structural, energetic and electronic properties of nitroisophthalamide receptors, i.e., di(benzyl)- (R1), di(hexafluoro)- (R2), di(chloro-,tetrafluoro)- (R3), di(hexachloro)-(R4), di(fluoro-,tetrachloro)-nitroisophthalamide (R5), and their complexes with C2H3O2-, C7H5O2-, NO3-, H2PO4-, and ClO4- oxoanions were computed and obtained using the density functional theory calculations at the B3LYP/6-31G(d,p) theoretical level in gas phase. According to the computed results, all of oxoanions can form the stable complexes with amide receptors R1-R5 via exothermic process in which receptor R1 is found to interact with oxoanions through hydrogen bonds whereas the receptors R2-R5 are found to interact with oxoanion through both of hydrogen and halogen bonds. It is clearly seen that acetate ion displays the strongest complexation interaction with all receptors compared to the other oxoanions. In addition, electronic properties of receptors R1-R5 in both gas and DMSO phases are modified after complexation with oxoanions. Therefore, the designed amide receptors may be potentially used for oxoanion sensing application.

Newest applications of molecularly imprinted polymers for extraction of contaminants from environmental and food matrices: A review

This paper presents an overview of the recent applications of molecularly imprinted polymers (MIPs) to sample preparation. The review is thought to cover analytical procedures for extraction of contaminants (mainly illegal/noxious organic compounds) from food and environmental matrices, with a particular focus on the various pre-concentration/cleanup techniques, that is offline and online solid-phase extraction (SPE), dispersive SPE (d-SPE), magnetic SPE (MSPE), solid-phase microextraction (SPME) and stir-bar sorptive extraction (SBSE), applied before instrumental quantification. The selectivity and extraction efficiency of MIP-based sorbent phases are critically discussed, also in relation to the physical-chemical properties resulting from the synthetic procedures. A variety of molecularly imprinted sorbents is presented, including hybrid composites embedding carbon nanomaterials and ionic liquids. The analytical performance of MIP materials in sample preparation is commented as function of the complexity of the matrix, and it is compared to that exhibited by (commercial) aspecific and/or immunosorbent phases.

Recent advances in applications of nanomaterials for sample preparation

Sample preparation is a key step for qualitative and quantitative analysis of trace analytes in complicated matrix. Along with the rapid development of nanotechnology in material science, numerous nanomaterials have been developed with particularly useful applications in analytical chemistry. Benefitting from their high specific areas, increased surface activities, and unprecedented physical/chemical properties, the potentials of nanomaterials for rapid and efficient sample preparation have been exploited extensively. In this review, recent progress of novel nanomaterials applied in sample preparation has been summarized and discussed. Both nanoparticles and nanoporous materials are evaluated for their unusual performance in sample preparation. Various compositions and functionalizations extended the applications of nanomaterials in sample preparations, and distinct size and shape selectivity was generated from the diversified pore structures of nanoporous materials. Such great variety make nanomaterials a kind of versatile tools in sample preparation for almost all categories of analytes.

On-line microextraction of moxifloxacin using Fe3O4 nanoparticle-packed in-tube SPME

An in-tube SPME based on the use of a Fe₃O₄ nanoparticles-packed tube has been reported.

Electrochemically controlled in-tube solid phase microextraction of naproxen from urine samples using an experimental design

Electrochemically controlled in-tube SPME approach, which increased the sensitivity and decreased the extraction time, was reported.