: The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Introducing an alternate conjugated material for enhanced lead(II) capturing from wastewater

Electrochemical impedance spectroscopy (EIS) is a powerful technique used for the analysis of interfacial properties related to bio-recognition events occurring at the electrode surface, such as antibody-antigen recognition, substrate-enzyme interaction, or whole cell capturing. Thus, EIS could be exploited in several important biomedical diagnosis and environmental applications. However, the EIS is one of the most complex electrochemical methods, therefore, this review introduced the basic concepts and the theoretical background of the impedimetric technique along with the state of the art of the impedimetric biosensors and the impact of nanomaterials on the EIS performance. The use of nanomaterials such as nanoparticles, nanotubes, nanowires, and nanocomposites provided catalytic activity, enhanced sensing elements immobilization, promoted faster electron transfer, and increased reliability and accuracy of the reported EIS sensors. Thus, the EIS was used for the effective quantitative and qualitative detections of pathogens, DNA, cancer-associated biomarkers, etc. Through this review article, intensive literature review is provided to highlight the impact of nanomaterials on enhancing the analytical features of impedimetric biosensors.

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Electrochemical Impedance Spectroscopy (EIS): Principles, Construction, and Biosensing Applications

https://pubs.rsc.org/en/content/articlepdf/2020/cc/d0cc05650b

Electrochemical non-enzymatic glucose sensors: recent progress and perspectives

Organometallic nanowires with luminescent and current‐modulating properties were self‐assembled from cyclometalated/terpyridyl platinum(II) complexes with auxiliary arylisocyanide/arylacetylide ligands and incorporated into a compact organic light‐emitting field‐effect transistor (see picture) by solution‐processable protocols. The nanowires exhibit both electron and hole mobilities of 0.1 cm2 V−1 s−1.

Semiconducting and Electroluminescent Nanowires Self-Assembled from Organoplatinum(II) Complexes†

Development of an impedimetric non enzymatic sensor based on ZnO and Cu doped ZnO nanoparticles for the detection of glucose

Study of organic thin film transistors based on nickel phthalocyanine: effect of annealing

Calixarene membranes on semiconductor substrates for E.I.S. chemical sensors

Optical and electrical study of chromogenic calix(4)arene derivatives

Many investigations on dielectric, electronic and spectroscopic characterisation have been achieved on molecular materials for their eventual application as sensors or electronic devices. Calixarenes exhibit an interesting supramolecular structure on account of their receptor properties; they represent receptor molecules of widely varying size for metal cations and organic molecules. They are comparatively new cyclic condensation products of para-substituted phenols and formaldehyde; they form a series of well-defined cyclic oligomers. Therefore, the variation of cavity size according to the requirements (i.e. ion sensitivities) of different guests is possible. The macro cycles are characterised by the phenolic unit number (4,6,8,…). p -tert-Butyl calix[ n ]arene ( n = 4 and 8), used as a sensitive membrane incorporating the receptor molecule on the top of the gate oxide, was characterised. The calixarene was thermally evaporated on the oxide to form a semiconductor-oxide-film capacitance structure. It is shown, by means of structural and spectroscopic studies, that films have good adherence to the oxide and are chemically very stable allowing the use of such a structure as a chemical sensor in liquid media. The studies of ISFET structure using calix[ n ]arene membranes are in progress, showing an interesting selectivity and stability.

R. Ben Chaabane

Papers

Development of an impedimetric non enzymatic sensor based on ZnO and Cu doped ZnO nanoparticles for the detection of glucose

Study of organic thin film transistors based on nickel phthalocyanine: effect of annealing

Calixarene membranes on semiconductor substrates for E.I.S. chemical sensors

Optical and electrical study of chromogenic calix(4)arene derivatives

Study of the membrane morphology and investigation of sensitivity to ions for sensors based on calixarenes