Quantum computational, spectroscopic and molecular docking studies on 2-acetylthiophene and its bromination derivative

Computational analysis of anti-cancer drug hydroxyurea adsorption on nanocages of gold, silver and copper: SERS and DFT assessment

The use of nanostructures in targeted drug delivery is effective in decreasing anticancer drug toxicity. Here, we discuss the theoretically predicted adsorption and interaction behavior of hydroxyurea [HU] with nano metal cages (nmC). HU interact the nmC through the N4 in primary amine with energies of -29.776, -30.684 and -22.105 kcal/mol for Au, Ag and Cu cage, respectively. As a result of reactivity studies, HU complexes with nmC (Au/Ag/Cu) are becoming more electrophilic and this gives the nmC system their bioactivity. It is suggested that nanocage is going to change the FMO's energy levels by means of absorption, so that it is used in drug administration. DOS and MEP were accomplished to gain additional understandings into the reactivity of proposed complexes. Method for improving the Raman signal of biomolecules is surface enhanced Raman scattering (SERS), which uses nanosized metal substrates. Chemical enhancement is evidenced by Mulliken charge distributions of all systems for detection and chemical compositions and exerts a significant role in determining them. In HU complexes containing nmC (Au/Ag/Cu), electron density was detected via ELF and LOL calculations. Based on the results of a non-covalent interaction (NCI) analysis, Van der Waals/hydrogen bonds/repulsive steric - interactions have been found. The title compound will also be analyzed in order to determine its bioactivity and drug likeness parameters, as a result, we will able to create a molecule with a highly favorable pharmacological profile and use the docking method to determine the values of the interaction energies for drug delivery. This study suggests that adsorption of drugs on nanocage surface occurs physically and functionalizing the nanocage has increased adsorption energy.

Electrochemical, Ultrasensitive, and Selective Detection of Nitrite and H2O2: Novel Macrostructured Phthalocyanine with Composite MWCNTs on a Modified GCE

In the current study, the synthesis of tetra-4-(2-methoxyphenoxy) carboxamide cobalt(II) amide-bridged phthalocyanine (CoTMePhCAPc) is described, as well as its characterization by Fourier transform infrared (FT-IR), UV-visible, and mass spectroscopy; powder X-ray diffraction (PXRD); thermogravimetric analysis (TGA); scanning electron microscopy (SEM); and electrochemistry. Sensing of nitrite (NO₂^-) and hydrogen peroxide (H₂O₂) simultaneously was done on CoTMePhCAPc with the composite multiwalled carbon nanotube (MWCNT)-modified glassy carbon electrode (CoTMePhCAPc/MWCNT/GCE) in the range of linear absorption (NO₂^- and H₂O₂: CV 50-750, differential pulse voltammetry (DPV) 50-750, CA 50-500 nmol L^-1), lower detection limit (NO₂^- and H₂O₂: CV 10.5 and 12.5, DPV 10.5 and 11.2, CA 6.0 and 5.5 nmol L^-1), and sensitivity (NO₂^- and H₂O₂: CV 0.379 and 0.529, DPV 0.043 and 0.049, CA 0.033 and 0.040 μA nM^-1 cm^-2). The composite electrode exhibits improved electrocatalytic behavior compared to modified electrodes for nitrite and H₂O₂. The CoTMePhCAPc/MWCNT/GCE sensor displays good selectivity even in the presence of an excess of interfering metal ions and biomolecules at the applied potentials of +400 mV (nitrite) and -400 mV (H₂O₂). Moreover, the fabricated sensor was studied with various phosphate-buffered saline (PBS) (pH 5-9) electrolyte solutions. The unknown H₂O₂ concentration in blood samples and apple juice and nitrite concentration in drinking water and butter leaf lettuce were all measured using the usual addition method. Docking analysis clearly indicates that the ligand shows excellent inhibition activity toward the three subjected protein molecules.

Revealing the incorporation of an NH2 group into the edge of carbon dots for H2O2 sensing via the C-N⋯H hydrogen bond interaction

We investigated hydrogen peroxide (H₂O₂) sensing on NH₂-functionalized carbon dots (Cdots) for three different -NH₂ positions, and the N atom was found to be the active site using a quantum computational approach. B3LYP and 6-31G(d,p) were used for density functional theory (DFT) ground state calculations, whereas CAM-B3LYP and the same basis set were used in time-dependent density functional theory (TD-DFT) excited state calculations. Structural optimization showed that the H₂O₂ is chemisorbed on 1-sim via a C-N⋯H hydrogen bond interaction with an adsorption energy of -10.61 kcal mol^-1. Mulliken atomic charge distributions and electrostatic potential (ESP) analysis were both used to determine reactivity of the molecules at the atomic level. For in-depth analysis of the ground states, we utilized Frontier molecular orbital (FMO) theory, quantum theory of atoms in molecules (QTAIM), and non-covalent interaction (NCI) index analysis. In addition, we also present UV-vis absorption spectra and charge transfer lengths to understand the mechanism of H₂O₂ sensing in excited states. Based on the molecular and electronic properties of the NH₂-Cdots, it was shown that 1-sim is a potential candidate for use as an electrochemical sensor for H₂O₂ sensing. Whereas 3-sim is believed to be a potential candidate for use as an optical sensor of H₂O₂ based on the UV-vis characteristics via photoinduced charge transfer.

Non-covalent interaction, adsorption characteristics and solvent effect of procainamide anti-arrhythmias drug on silver and gold loaded silica surfaces: SERS spectroscopy, density functional theory and molecular docking investigations†

First-principle calculations were systematically carried out to explore the structural and electronic properties of the non-covalent interaction of procainamide (PA) anti-arrhythmias drug molecules on silver-loaded and gold-loaded silica nanostructures. Computed adsorption energies presented a higher affinity of PA towards the Ag–SiO₂ as compared with Au–SiO₂ surfaces. The non-covalent interaction analysis revealed a weak van der Waals type of forces and hydrogen bonding, associated with a noticeable repulsive steric interaction. It was conceived that silver and gold decorated silica can be used for drug administration in biological systems due to the fact that their frontier molecular orbital energy levels were considerably altered upon absorption, decreasing the pertinent energy gaps. Moreover, the electronic spectra of PA⋯Ag–SiO₂ and PA⋯Au–SiO₂ structures investigated in different solvents display a notable blue shift, suggesting that noble metal-loaded silica can be effective in the context of drug delivery systems. Therefore, silver- and gold-decorated silica of three possible drug adsorption scenarios was fully analyzed to realize the associated bioactivity and drug likeness. Theoretical findings suggest that Ag- and Au–SiO₂ nanocomposites can be considered potential drug delivery platforms for procainamide in medication protocols.

The structural and electronic properties of the non-covalent interaction of procainamide (PA) anti-arrhythmias drug molecules on silver-loaded and gold-loaded silica nanostructures were explored using first-principle calculations.