Interactions of the β-cyclodextrin (β-CD) ligand with Na+, Cu+, Mg2+, Zn2+, and Al3+ cations were investigated using density functional theory modeling. The objective this study was to give insight into mechanism cation complexation. Two groups conformers found. first group preserved initial orientation glucopyranose residues inside β-CD ligand. mutual strongly affected by in second conformers. system interaction energy decomposed electrostatic (ES), Pauli orbital contributions Ziegler–Rauk...

In the present study, nucleophilic properties of adenine and guanine are examined by means density functional theory. H+ is used as a model electrophile. Two modes attack on bases considered: neutral molecule anion. Solvent effects modeled polarizable continuum model. Regioselectivity studied analyzing two contributions. The first one energetic ordering tautomers. second relative inherent reactivity sites in bases. Atomic softnesses calculated charge sensitivity analysis employed for this...

Doxorubicin (DOX) is a commonly used chemotherapeutic drug, from the anthracycline class, which genotoxic to neoplastic cells via DNA intercalation mechanism. It effective and universal; however, it also causes numerous side effects. The most serious of them are cardiotoxicity decrease in number myeloid cells. For this reason, targeted DOX delivery systems desirable, since they would allow lowering drug dose therefore limiting systemic Recently, synthetic dyes, particular Congo red (CR),...

Abstract By reducing the surface tension of air–water interface in alveoli, lung surfactant (LS) is crucial for proper functioning lungs. It also forms first barrier against inhaled pathogens. In this study we inspect interactions LS models with a dangerous air pollutant, benzo[a]pyrene (BaP). Dipalmitoylphosphatidylcholine (DPPC), 1‐palmitoyl‐2‐oleoylphosphatidylcholine, and their 1:1 mixture are used as models. Pressure‐area isotherms employed to macroscopic properties monolayers. We find...

Apart from being responsible for sufficient pulmonary compliance and preventing alveolar collapse, lung surfactant (LS) also forms the first barrier uptake of inhaled pathogens. As such it is susceptible to damage caused by various deleterious compounds present in air, e.g. oxidants capable oxidizing unsaturated LS lipids. This study examines consequences 20% lipids an model: a mixed 1 : DPPC POPC monolayer. POxnoPC (1-palmitoyl-2-(9-oxo-nonanoyl)-sn-glycero-3-phosphocholine) considered as...

Charge sensitivity analysis was originally introduced in the trivial-atom resolution. Here, we extend this resolution into force-field atoms. The AMBERff99 employed. effective electronegativities and hardnesses were derived for five different population analyses (Mulliken, Hirschfeld, AIM, NPA Voronoi charges) by applying evolutionary algorithms.

The formation of inclusion complexes β-cyclodextrin was studied at the melting temperature guest compounds by differential scanning calorimetry. long-chain n-alkanes, polyaromatics, and organic acids were investigated calorimetry IR spectroscopy. complexation ratio compared with results obtained in an aqueous environment. stability structure various stoichiometries estimated quantum chemistry molecular dynamics calculations. Comparison experimental theoretical confirmed possible multiple...

Quantum-chemical calculations and molecular dynamics simulation were applied to a model self-organization process of Congo red (CR) molecules in aqueous solution the impact doxorubicin (DOX) on such process. It was demonstrated that both pure CR/CR mixed CR/DOX dimers stable. Van der Waals interactions between aromatic units responsible for stacked dimer formation. An important source stabilization polarization energy. In long range, electrostatic main driving force leading complexation....

Gliclazide (GLC) inclusion complexes with β-cyclodextrin (βCD) were studied by UV-VIS and FT-IR spectroscopy. The recorded spectra confirmed the formation of GLC-βCD binary GLC-(βCD)2 ternary in aqueous solutions. measurements carried out for a number temperatures allowed to determine binding constants complexation reactions. bioavailability was determined using n-octanol/water partition coefficient. Experimental studies supplemented theoretical calculations. Quantum-chemical calculations...

Lung surfactant subdomains enriched with DPPG limit the penetration of benzo[<italic>a</italic>]pyrene molecules into bulk solution.

The present study deals with interaction of two air pollutants: dibenzodioxin, DD, and its' monochlorinated derivative, 2-chlorodibenzodioxin, 2CLDD, models the lung surfactant (LS) system. A monolayer composed DPPC POPC in 1:1 molar ratio was used as a model LS. One component monolayers were also examined, to interiors LC LE domains LS, respectively. Molecular dynamics simulations measurements surface pressure isotherms, well polarization modulation-infrared reflection-absorption spectra...

Charge sensitivity analysis (CSA) in force-field atoms resolution was applied to describe the mutual polarization of reactants as well charge-transfer (CT) effects. An inclusion complex β-cyclodextrin with salicylic acid used a model system. Three CSA models were taken into account and verified on Born-Oppenheimer molecular dynamics (BOMD) trajectory. The differed terms equilibrium conditions imposed It demonstrated that is an important source stabilization, contrast results obtained from...

The uptake and distribution of doxorubicin in the MCF7 line breast-cancer cells were monitored by Raman measurements. It was demonstrated that bioavailability can be significantly enhanced applying Congo red. To understand mechanism delivery red supramolecular carriers, additional monolayer measurements molecular dynamics simulations on model membranes undertaken. Acting as scissors, particles cut aggregates incorporated them into small-sized clusters. mixed doxorubicin/Congo clusters...

Charge sensitivity analysis in AMBER force‐field resolution has been used quest for detectors of hydrogen bonds (HBs). The process HB formation was investigated on ab initio classical trajectories (B3LYP/6‐31G*) different nucleobase pairs. Several charge sensitivities, namely: electronegativity, hardness, Fukui function (FF), and polarization matrix, were analyzed. global constrained equilibria considered. It demonstrated that FF indices matrix elements are good formation. © 2013 Wiley...

A simple way to improve the accuracy of fragmentation methods is proposed. The formalism was applied elongation (ELG) method at restricted open-shell Hartree-Fock (ROHF) level theory. α-helix conformer polyglycine taken as a model system. modified ELG includes simplified electrostatic field resulting from point-charge distribution system's environment. In this long-distance polarization approximately into account. attenuates during process eventually disappear when final structure reached....

Partial atomic charges are important force field parameters. They usually computed by applying quantum-chemical calculations and the assumed population scheme. In this study polarization consistent scheme of deriving a charge distribution inside solute molecule is proposed. The environment effect explicitly taken into account distributing solvent molecules around target. performed analysis includes few computational schemes (HF, MP2, B3LYP, M026X), basis sets (cc-pvnz, n = 2, 3, …, 6),...

The behavior of four drugs from the family nucleoside analog reverse-transcriptase inhibitors (zalcitabine, stavudine, didanosine, and apricitabine) in a membrane environment was traced using molecular dynamics simulations. simulation models included bilayers monolayers composed POPC POPG phospholipids. It demonstrated that have higher affinity towards membranes than due to attractive long-range electrostatic interactions. results obtained for were consistent with those bilayers. accumulated...

Abstract The elongation method with intermediate mechanical and electrostatic embedding (ELG‐IMEE) is proposed. uses atomic charges generated by a charge sensitivity analysis (CSA) parameterized for three different population analyses, namely, the Merz–Singh–Kollman scheme, model 5, polar tensor. obtained CSA models were tested on two systems. Test calculations show that provides several times of decrease in difference energies testing reference comparison conventional approach (ELG)....

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Gliclazide (GLC) inclusion complexes with β-cyclodextrin (βCD) were studied by UV-VIS and FT-IR spectroscopy. The recorded spectra confirmed the formation of GLC-βCD binary GLC-(βCD)2 ternary in aqueous solutions. measurements carried out for a number temperatures allowed to determine binding constants complexation reactions. bioavailability was determined using n-octanol/water partition coefficient. Experimental studies supplemented theoretical calculations. Quantum-chemical calculations...