Enhanced sensing of bacteria biomarkers by ZnO and graphene oxide decorated PEDOT film.

Developing a biofilm biomarker detector and inhibitor will immensely benefit efforts geared at curbing infectious diseases and microbiologically induced corrosion of medical implants, marine vessels and buried steel pipelines. N-Acyl homoserine lactones (AHLs) are important biomarkers gram-negative bacteria use for communication. In this work, we investigated the interactions between three AHL molecules and graphene oxide (GO) and ZnO nanomaterials embedded in conjugated poly(3,4-ethylenedioxythiophene) (PEDOT) film. The results show that PEDOT/GO/ZnO detected AHLs to a considerable extent with adsorption enthalpies of -4.02, -4.87 and -4.97 KJ/mol, respectively, for N-(2-oxotetrahydrofuran-3-yl)heptanamide (AHL1), 2-hydroxy-N-(2-oxotetrahydrofuran-3-yl)nonanamide (AHL2) and (E)-3-(3-hydroxyphenyl)-N-(2-oxotetrahydrofuran-3-yl)acrylamide (AHL3) molecules. The ZnO nanoparticles facilitated charge redistribution and transfer, thereby enhancing the conductivity and overall sensitivity of the substrate toward the AHLs. The adsorption distance and sites of interactions further tuned the charge migration and signal generation by the substrate, thus affirming the suitability of the modeled thin film as a sensor material. Excellent stability and conductivity were maintained before and after the adsorption of each AHL molecule. Moreover, the desorption time for each AHL molecule was calculated, and the result affirmed that the modeled film materials are promising for developing highly sensitive biosensors.Communicated by Ramaswamy H. Sarma.

Increasing the Photovoltaic Power of the Organic Solar Cells by Structural Modification of the R-P2F-Based Materials.

CONTEXT: The present study aims to improve the performance of optoelectronics and photovoltaics by constructing an acceptor-donor-acceptor (A-D-A) molecule with a fullerene-free acceptor moiety. The study utilizes malononitrile and selenidazole derivatives to tailor the molecule for enhanced photovoltaic abilities. The study analyzes molecular properties and parameters like charge density, charge transport, UV absorption spectra, exciton binding energies, and electron density difference maps to determine the effectiveness of the tailored derivatives. METHODS: To optimize the geometric structures, the study used four different functionals (B3LYP, CAM-B3LYP, MPW1PW91, and É·B97XD) along with a double zeta valence basis set 6-31G(d, p) basis set. The study compared the results of the tailored derivatives with a reference molecule (R-P2F) to determine improvements in performance. The light harvesting efficiency of the molecules was analyzed by performing simulations in the gas and solvent phases (chloroform) based on the spectral overlap between the solar irradiance and the absorption spectra of the molecules. The open-circuit voltage (VOC) of each molecule was also analyzed, representing the maximum voltage that can be obtained from the cell under illuminated conditions. The findings indicated that the M1-P2F designed derivative is a more effective, with energy gap of 2.14 eV, and suitable candidate for non-fullerene organic solar cell application, based on various analyses such as power conversion efficiency, quantum chemical reactivity parameters, and electronic features.

High throughput computations of the effective removal of liquified gases by novel perchlorate hybrid material.

The utilization of hybrid materials in separation technology, sorbents, direct air capture (DAC) technology, sensors, adsorbents, and chiral material recognition has increased in the past decade due to the recognized impact of atmospheric pollutants and hazardous industrial gases on climate change. A novel hybrid material, perchlorate hybrid (PClH), has been proposed in this study for the effective sensory detection and trapping of atmospheric pollutants and industrial hazardous gases. The study evaluated the structural properties, adsorption mechanism, electronic sensitivity, and topological analysis of PClH using highly accurate computational methods (M062X-D3BJ/def2-ccpVTZ and DSDPBEP86/def2-ccpVTZ). The computational analysis demonstrated that PClH has considerable adsorption energies and favorable interaction with CO2, NO2, SO2, COCl2, and H2S. PClH is more suitable for detecting liquefiable gases such as COCl2, CO2, and SO2, and can be easily recovered under ambient conditions. Developing such materials can contribute to reducing hazardous gases and pollutants in the atmosphere, leading to a cleaner and safer environment.

Molecular Simulation of the Interaction of Diclofenac with Halogen (F, Cl, Br)-Encapsulated Ga12As12 Nanoclusters.

Diclofenac is one of the most frequently consumed over-the-counter anti-inflammatory agents globally, and several reports have confirmed its global ubiquity in several environmental compartments. Therefore, the need to develop more efficient monitoring/sensing devices with high detection limits is still needed. Herein, quantum mechanical simulations using density functional theory (DFT) computations have been utilized to evaluate the nanosensing efficacy and probe the applicability of Ga12As12 nanostructure and its engineered derivatives (halogen encapsulation F, Br, Cl) as efficient adsorbent/sensor materials for diclofenac. Based on the DFT computations, it was observed that diclofenac preferred to interact with the adsorbent material by assuming a flat orientation on the surface while interacting via its hydrogen atoms with the As atoms at the corner of the GaAs cage forming a polar covalent As-H bond. The adsorption energies were observed to be in the range of -17.26 to -24.79 kcal/mol and therefore suggested favorable adsorption with the surface. Nonetheless, considerable deformation was observed for the Br-encapsulated derivative, and therefore, its adsorption energy was observed to be positive. Additionally, encapsulation of the GaAs nanoclusters with halogens (F and Cl) enhanced the sensing attributes by causing a decrease in the energy gap of the nanocluster. And therefore, this suggests the feasibility of the studied materials as potentiometric sensor materials. These findings could offer some implications for the potential application of GaAs and their halogen-encapsulated derivatives for electronic technological applications.

Interaction of 5-Fluorouracil on the Surfaces of Pristine and Functionalized Ca12O12 Nanocages: An Intuition from DFT.

The utilization of nanostructured materials for several biomedical applications has tremendously increased over the last few decades owing to their nanosizes, porosity, large surface area, sensitivity, and efficiency as drug delivery systems. Thus, the incorporation of functionalized and pristine nanostructures for cancer therapy offers substantial prospects to curb the persistent problems of ineffective drug administration and delivery to target sites. The potential of pristine (Ca12O12) and formyl (-CHO)- and amino (-NH2)-functionalized (Ca12O12-CHO and Ca12O12-NH2) derivatives as efficient nanocarriers for 5-fluorouracil (5FU) was studied at the B3LYP-GD3(BJ)/6-311++G(d,p) theoretical level in two electronic media (gas and solvent). To effectively account for all adsorption interactions of the drug on the investigated surfaces, electronic studies as well as topological analysis based on the quantum theory of atoms in molecules (QTAIM) and noncovalent interactions were exhaustively utilized. Interestingly, the obtained results divulged that the 5FU drug interacted favorably with both Ca12O12 and its functionalized derivatives. The adsorption energies of pristine and functionalized nanostructures were calculated to be -133.4, -96.9, and -175.6 kcal/mol, respectively, for Ca12O12, Ca12O12-CHO, and Ca12O12-NH2. Also, both topological analysis and NBO stabilization analysis revealed the presence of interactions among O3-H32, O27-C24, O10-C27, and N24-H32 atoms of the drug and the surface. However, 5FU@Ca12O12-CHO molecules portrayed the least adsorption energy due to considerable destabilization of the molecular complex as revealed by the computed deformation energy. Therefore, 5FU@Ca12O12 and 5FU@Ca12O12-NH2 acted as better nanovehicles for 5FU.

Computational design and molecular modeling of the interaction of nicotinic acid hydrazide nickel-based complexes with H2S gas.

The application of nickel complexes of nicotinic acid hydrazide ligand as a potential gas-sensor and adsorbent material for H2S gas was examined using appropriate density functional theory (DFT) calculations with the ωB97XD/Gen/6-311++G(d,p)/LanL2DZ method. The FT-IR spectrum of the synthesized ligand exhibited a medium band at 3178 cm-1 attributed to ν(NH) stretching vibrations and strong bands at 1657 and 1600 cm-1 corresponding to the presence of ν(C[double bond, length as m-dash]O) and ν(C[double bond, length as m-dash]N) vibration modes. In the spectrum of the nickel(ii) complex, the ν(C[double bond, length as m-dash]O) and ν(C[double bond, length as m-dash]N) vibration bands experience negative shifts to 1605 cm-1 and 1580 cm-1, respectively, compared to the ligand. This indicates the coordination of the carbonyl oxygen and the azomethine nitrogen atoms to the Ni2+ ion. Thus, the sensing mechanism of the complexes indicated a short recovery time and that the work function value increases for all complexes, necessitating an excellent H2S gas sensor material. Thus, a profound assertion was given that the complex sensor surfaces exhibited very dense stability with regards to their relevant binding energies corresponding to various existing studies.

Detection of Carbon, Sulfur, and Nitrogen Dioxide Pollutants with a 2D Ca12O12 Nanostructured Material.

In recent times, nanomaterials have been applied for the detection and sensing of toxic gases in the environment owing to their large surface-to-volume ratio and efficiency. CO2 is a toxic gas that is associated with causing global warming, while SO2 and NO2 are also characterized as nonbenign gases in the sense that when inhaled, they increase the rate of respiratory infections. Therefore, there is an explicit reason to develop efficient nanosensors for monitoring and sensing of these gases in the environment. Herein, we performed quantum chemical simulation on a Ca12O12 nanocage as an efficient nanosensor for sensing and monitoring of these gases (CO2, SO2, NO2) by employing high-level density functional theory modeling at the B3LYP-GD3(BJ)/6-311+G(d,p) level of theory. The results obtained from our studies revealed that the adsorption of CO2 and SO2 on the Ca12O12 nanocage with adsorption energies of -2.01 and -5.85 eV, respectively, is chemisorption in nature, while that of NO2 possessing an adsorption energy of -0.69 eV is related to physisorption. Moreover, frontier molecular orbital (FMO), global reactivity descriptors, and noncovalent interaction (NCI) analysis revealed that the adsorption of CO2 and SO2 on the Ca12O12 nanocage is stable adsorption, while that of NO2 is unstable adsorption. Thus, we can infer that the Ca12O12 nanocage is more efficient as a nanosensor in sensing CO2 and SO2 gases than in sensing NO2 gas.

Electrocatalytic activity of metal encapsulated, doped, and engineered fullerene-based nanostructured materials towards hydrogen evolution reaction.

The utilization of nanostructured materials as efficient catalyst for several processes has increased tremendously, and carbon-based nanostructured materials encompassing fullerene and its derivatives have been observed to possess enhanced catalytic activity when engineered with doping or decorated with metals, thus making them one of the most promising nanocage catalyst for hydrogen evolution reaction (HER) during electro-catalysis. Prompted by these, and the reported electrochemical, electronic and stability advantage, an attempt is put forward herein to inspect the metal encapsulated, doped, and decorated dependent HER activity of C24 engineered nanostructured materials as effective electro-catalyst for HER. Density functional theory (DFT) calculations have been utilized to evaluate the catalytic hydrogen evolution reaction activity of four proposed bare systems: fullerene (C24), calcium encapsulated fullerene (CaencC24), nickel-doped calcium encapsulated fullerene (NidopCaencC24), and silver decorated nickel-doped calcium encapsulated (AgdecNidopCaencC24) engineered nanostructured materials at the TPSSh/GenECP/6-311+G(d,p)/LanL2DZ level of theory. The obtained results divulged that, a potential decrease in energy gap (Egap) occurred in the bare systems, while a sparing increase was observed upon adsorption of hydrogen onto the surfaces, these surfaces where also observed to maintain the least EH-L gap while the AgdecNidopCaencC24 surface exhibited an increased electrocatalytic activity when compared to others. The results also showed that the electronic properties of the systems evinced a correspondent result with their electrochemical properties, the Ag-decorated surface also exhibited a proficient adsorption energy [Formula: see text] and Gibb's free energy (ΔGH) value. The engineered Ag-decorated and Ni-doped systems were found to possess both good surface stability and excellent electro-catalytic property for HER activities.

Experimental and theoretical studies of the influence of alkyl groups on the photovoltaic properties of (E)-6-((2, 3-dihydroxylnaphthalene)diazenyl)-1H-benzoisoquinoline-1,3-dione-based organic solar cell.

The manipulation of the active dye material for application in dye-sensitized solar cell (DSSC) using simple or bulky group substituents is necessary for improved dye performance. Herein, we carried out a combined experimental and theoretical studies of different alkylated novel reactive (E)-6-(2,3-dihydroxyl naphthalene diazinyl)-1H-benzoisoquinoline-1,3-dione azo-based dyes using spectral (FTIR, UV-visible, and NMR) analysis and electronic structure theory method based first principle density functional theory (DFT) calculations to investigate the molecular electronic properties, structural analysis, excitation behavior, and the theoretical potential application in photovoltaic cell. The synthesized azo dye (azoD) was theoretically modeled by varying the number of alkyl chains denoted as AzoD1, AzoD2, AzoD3, and AzoD4 to represent azo dyes having ten (10), twelve (12), fourteen (14), and sixteen (16) alkyl chain length respectively. From the natural bond orbital (NBO) analysis, the higher stabilization energies, 227.80 and 227.77 kcal/mol respectively, recorded for AzoD1 and AzoD4 may be due to extra orbital contribution by π*(N21-N22) to π*C54-C56 31.19 eV for AzoD1 and π*(N21-N22) → π*(C53-C55) 31.43 eV AzoD4 confirming that chain length affected the orbital interaction of the molecules. The driving force (ΔGinject) of electron injection into the TiO2 surface (- 1.92 to - 1.93) shown in this study is indicative that alkylated azo dyes are good for improved DSSCs performance. Again, the open circuit voltage (Voc) of 1.090 (AzoD1), 1.092 (AzoD2), 1.093 (AzoD3), and 1.095 (AzoD4) are also evidence of the suitability of azo dyes as photosensitizers. All the spectroscopic analysis, FTIR, UV-visible, and NMR combined with theoretical calculations, provided accurate data for characterizing the titled azo dye compound and showed that it has good photophysical properties. The presence of alkyl groups and chain length promoted the stability of the dyes thereby making them suitable for application in DSSCs. Increase in chain length as well enhanced the electron injection into the conduction band of the semiconductor.

Metal-Doped Al12N12X (X = Na, Mg, K) Nanoclusters as Nanosensors for Carboplatin: Insight from First-Principles Computation.

This theoretical study focuses on the adsorption, reactivity, topological analysis, and sensing behavior of metal-doped (K, Na, and Mg) aluminum nitride (Al12N12) nanoclusters using the first-principle density functional theory (DFT). All quantum chemical reactivity, natural bond orbital (NBO), free energies (ΔG, ΔH), and sensor parameters were investigated using the ωB97XD functional with the 6-311++G(d,p) basis set. The trapping of carboplatin (cbp) onto the surfaces of doped Al12N12 was studied using four functionals PBE0-D3, M062X-D3, ωB97XD, and B3LYP-D3 at the 6-311++G(d,p) basis set. Overall, the substantial change in the energy gap of the surfaces after the adsorption process affects the work function, field emission, and the electrical conductivity of the doped clusters, hence making the studied surfaces a better sensor material for detecting carboplatin. Higher free energies of solvation were obtained in polar solvents compared to nonpolar solvents. Moreover, negative solvation energies and adsorption energies were obtained, which therefore shows that the engineered surfaces are highly efficient in trapping carboplatin. The relatively strong adsorption energies show that the mechanism of adsorption is by chemisorption, and K- and Na-doped metal clusters acted as better sensors for carboplatin. Also, the topological analysis in comparison to previous studies shows that the nanoclusters exhibited very high stability with regard to their relevant binding energies and hydrogen bond interactions.

Meta-Hybrid Density Functional Theory Prediction of the Reactivity, Stability, and IGM of Azepane, Oxepane, Thiepane, and Halogenated Cycloheptane.

The application of plain cycloalkanes and heterocyclic derivatives in the synthesis of valuable natural products and pharmacologically active intermediates has increased tremendously in recent times with much attention being paid to the lower cycloalkane members. The structural and molecular properties of higher seven-membered and nonaromatic heterocyclic derivatives are less known despite their stable nature and vast application; thus, an insight into their structural and electronic properties is still needed. Appropriate quantum chemical calculations utilizing the ab initio (MP2) method, meta-hybrid (M06-2X) functional, and long-range-separated functionals (ωB97XD) have been utilized in this work to investigate the structural reactivity, stability, and behavior of substituents on cycloheptane (CHP) and its derivatives: azepane, oxepane, thiepane, fluorocycloheptane (FCHP), bromocycloheptane (BrCHP), and chlorocycloheptane (ClCHP). Molecular global reactivity descriptors such as Fukui function, frontier molecular orbitals (FMOs), and molecular electrostatic potential were computed and compared with lower members. The results of two population methods CHELPG and Atomic Dipole Corrected Hirshfeld Charges (ADCH) were equally compared to scrutinize the charge distribution in the molecules. The susceptibility of intramolecular interactions between the substituents and cycloalkane ring is revealed by natural bond orbital analysis and intramolecular weak interactions by the independent gradient model (IGM). Other properties such as atomic density of states, intrinsic bond strength index (IBSI), and dipole moments are considered. It is acclaimed that the strain effect is a major determinant effect in the energy balance of cyclic molecules; thus, the ring strain energies and validation of spectroscopic specificities with reference to the X-ray crystallographic data are also considered.

Vibrational Characterization and Molecular Electronic Investigations of 2-acetyl-5-methylfuran using FT-IR, FT-Raman, UV-VIS, NMR, and DFT Methods.

Spectroscopic (FT-IR, FT-Raman, UV-vis, and NMR) techniques have been extensively used for structural elucidation of compounds along with the study of geometrical and vibrational properties. Herein, 2-acetyl-5-methylfuran, a derivative of furan, was experimentally characterized and analyzed in details using FT-IR, FT-Raman, UV-vis, and 1H NMR spectroscopic techniques conducted in different solvents. The experimentally analyzed spectral results were carefully compared with theoretical values obtained using density functional theory (DFT) calculations at the B3LYP/6-311 + + G (d, p) method to support, validate, and provide more insights on the structural characterizations of the titled compound. The correlated experimental and theoretical structural vibrational assignments along with their potential energy distributions (PEDs) and all the spectroscopic spectral investigations of the titled structure were observed to be in good agreements with calculated results.

Evaluation of the excited state dynamics, photophysical properties, and the influence of donor substitution in a donor-[Formula: see text]-acceptor system.

There have been numerous attempts for the theoretical design of a better donor-[Formula: see text]-acceptor structural framework with improved absorption and emission properties. However, for effective dye designing, it is necessary to understand the electronic and photophysical properties of the dye systems. In this work, we report a detailed density functional theory (DFT) and time-dependent density functional theory (TD-DFT) investigations of the excited state characteristics and the influence of various groups (-HCO, =CH2, (-CH3)2, (HCO)2, and (-OCH3)2) attached to the donor group (-NH2) in a p-nitroaniline D-[Formula: see text]-A system which are symbolized respectively as p-nitroaniline (A), N,N-dimethylnitroaniline (A2), N,N-dicarbonylnitroaniline (A3), N-methylenenitroaniline (A4), and N,N-dimethoxynitroaniline (A5). The first principles DFT and TD-DFT calculations from the ground state (S0) to the first five excited states: (S0→S1), (S0→S2), (S0→S3), (S0→S4), and (S0→S5) were utilized to explore the reactivity of D-[Formula: see text]-A system using the conceptual DFT approach, characterization of electron excitation using the hole-electron analysis, visual study of the various real space functions in the hole-electron framework, density of states (DOS), measurement of charge transfer (CT) length of electron excitation ([Formula: see text]), measurement of the overlapping degrees of hole and electron of electron excitation ([Formula: see text]), interfragment charge transfer (IFCT) during electron excitation, and the second-order perturbation energy analysis from the natural bond orbitals (NBO) computation. Results of the excitation studies show that all the studied compounds exhibited an n→[Formula: see text]* localized type for first excitations (S0→S1) on -NO2 group in A, A2, A4, and A5 and -NCl2 in A3. [Formula: see text]→[Formula: see text]* charge transfer excitations were confirmed for S0→S2/S4/S5 in A and A2, S0→S3/S4/S5 in A3 and A5, and S0→S4/S5 in A4. The NBO second-order perturbation energy analysis suggest that the most significant hyperconjugative interactions were [Formula: see text] (54.43kcal/mol), [Formula: see text] (40.82kcal/mol), [Formula: see text] (11.67kcal/mol), [Formula: see text] (29.52kcal/mol), [Formula: see text] (11.55kcal/mol), [Formula: see text] (23.40kcal/mol), and [Formula: see text] (24.88kcal/mol) [Formula: see text](24.64kcal/mol), which respectively corresponds to the A, A2, A3, A4, and A5 D-[Formula: see text]-A systems under investigation, and these strong interactions stabilize the systems.

Investigation on electronic structure, vibrational spectra, NBO analysis, and molecular docking studies of aflatoxins and selected emerging mycotoxins against wild-type androgen receptor.

The geometry, frontier molecular orbitals (FMOs), vibrational, NBO analysis, and molecular docking simulations of aflatoxins (B1, B2, M1, M2, G1, G2), zearalenone (ZEA) emodin (EMO), alternariol (AOH), alternariol monoethyl ether (AMME), and tenuazonic acid (TeA) mycotoxins have been extensively theoretically studied and discussed based on quantum density functional theory calculations using Gaussian 16 software package. The theoretical computation for the geometry optimization, NBOs, and the molecular docking interaction was conducted using Density Functional Theory with B3LYP/6-31+G(d,p), NBO program, and AutoDock Vina tools respectively. Charge delocalization patterns and second-order perturbation energies of the most interacting natural bond orbitals (NBOs) of these mycotoxins have also been computed and predicted. Interestingly, among the mycotoxins investigated, aflatoxin G1 is seen to give the strongest stabilization energy while Zearalenone shows the highest tendency to accept electron(s) and emodin, an emerging mycotoxin gave the best binding pose within the androgen receptor pocket with a mean binding affinity of -7.40 kcal/mol.

Vibrational, electronic, spectroscopic properties, and NBO analysis of p-xylene, 3,6-difluoro-p-xylene, 3,6-dichloro-p-xylene and 3,6-dibromo-pxylene: DFT study.

This study explains the vibration and interaction of p-xylene and effect of three elements (fluorine, chlorine and bromine) of the halogen family substitution on it. Basic chemistry of four, compounds p-xylene (PX); 3,6-diflouro-p-xylene (DFPX); 3,6-dichloro-p-xylene (DCPX) and 3,6-dibromo-p-xylene (DBPX) has been explained extensively using theoretical approach. Vibrational energy distribution analysis (VEDA) software was used to study the potential energy distribution (PED) analysis, bond length, bond angles and dihedral angles of PX, DFPX, DCPX, DBPX after optimization with GAUSSIAN 09 software. The trend in chemical reactivity and stability of the studied compounds was observed to show increasing stability and decreasing reactivity moving from DBPX, DCPX, DFPX to PX and this was obtained from the calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) values. Our results show that PX is the best electron donor (best nucleophile) while DBPX is the best electron acceptor (the best electrophile). We also observed that the substituted halogen increases the value of the bond angles but the effect is reduced as the size of the halogen increases. The maximum intensity and the frequency value for the maximum intensity of the different compounds was determined using the VEDA 04 software. From our natural bond orbital (NBO) 7.0 program analysis, the studied compounds are said to show biological activities as well as the intramolecular hyperconjugative interactions responsible for stabilizing the compounds. The NBO results also revealed that the non-bonding interaction existing between the lone pair electron on the halogen atoms and the aromatic ring increases the stability of the halogen substituted para-xylene molecules. Multiwfn: A Multifunctional Wavefunction Analyzer was used for the spectroscopic plots.