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Pyrimethamine is an effective drug in the cancer cell treatment and is a dihydrofolate reductase inhibitor. In this work, the amount of drug loading up on CNT and its cytotoxicity effect upon MCF-7 cell lines was surveyed. The novel applications of some drugs and nanocarriers can induce the differentiation of adipose mesenchymal cells into nerve cells. Hence carbon nanotube-pyrimethamine was used to differentiate mesenchymal stem cells into the neural category, for the first time. The results of NSE and NFM gene expression level were evaluated using the real-time PCR. A detailed study on the interaction between pyrimethamine anticancer drug and (6, 0) zigzag single-walled carbon nanotube was performed by DFT/B3LYP and DFT/M06-2X with 6-31G*
The structural, electronic and magnetic properties of the MIL-47(Mn) metal–organic framework are investigated using first principles calculations. We find that the large-pore structure is the ground state of this material. We show that upon transition from the large-pore to the narrow-pore structure, the magnetic ground-state configuration changes from antiferromagnetic to ferromagnetic, consistent with the computed values of the intra-chain coupling constant. Furthermore, the antiferromagnetic and ferromagnetic configuration phases have intrinsically different electronic behavior: the former is semiconducting, the latter is a metal or half-metal. The change of electronic properties during breathing posits MIL-47(Mn) as a good candidate f
For the first time, we have investigated the interaction between pristine and doped carbon nanotubes (CNTs), and 5-fluorouracil (5-FU) using density functional theory (DFT) method. Geometry optimization, vibrational frequencies, frontier molecular orbital gaps as well as NMR, NBO, and AIM analyses were employed at M06-2X/6-31G(d,p) level. While weak adsorption occurs for 5-FU with pristine CNT (-5.79 kcal mol−1), the 5-FU molecule tends to be chemisorbed to doped CNTs (−40 and −29.2 kcal mol−1 upon Al- and Si-doping, respectively). Our results suggest that Al-doped CNTs is expected to have promising application in the field of drug delivery.
Polyester dendrimers are mostly non-toxic and this advantage besides biodegradability gives them a great chance of success in the field of drug delivery. This study investigates electronic and structural characteristics of ibuprofen complexation with polyester G1 dendrimer using DFT calculations. Optimized structural geometries, interaction energies, NMR, NBO, and AIM analyses, revealed that the stability of G1:Ibu complex could be attributed to the intermolecular hydrogen bonds formed between the functional groups of polyester G1 dendrimer and ibuprofen molecule. All calculations were repeated using a self-consistent reaction field (SCRF) and polarizable continuum model (PCM) to consider implicit solvent effects and the outcomes were in li
Due to unique features in surface activity, thermal stability, electrical and thermal conductivity, and compatibility with biomolecules such as DNA and proteins, carbon-based nanoparticles are raised potential as a candidate for various applications such as catalytic processes, drug delivery, light, and electrical engineering. Based on this premise, thermodynamic features of pure, graphene, and carbon nanotube (CNT)-based gold nanoparticles (AuNPs) are investigated using molecular dynamics approach. Melting, heat capacity, thermal conductivity, contact angle of molten AuNPs, and phase transition are calculated as indicators of thermodynamic properties of pure and carbon-based AuNPs. Simulation results indicate that the presence of a carbon
Hydrogen cyanide (HCN) adsorption on pristine and B–N doped biphenylene nanosheets was investigated by means of density functional theory calculations. According to biphenylene geometry, all distinct possible B–N substitutions were designed. Adsorption energy and electronic structure at the level of M062X/6-31?g (d,p) theory were computed for all possible geometries. Our results reveal that pristine biphenylene nanosheet is not a suitable candidate for HCN detection. Also, for B–N doping, the sensitivity of the nanosheet depends on the B–N doped configuration. One of these derivative structures shows higher sensitivity to HCN adsorption due to the greater change in electronic properties. Moreover, atoms in molecules a
Biological applications of single-walled carbon nanotubes (SWCNTs), including drug delivery, require their functionalization with various functional groups such as peptides. Recently, a biologically compatible peptide (named PW3 with the sequence of NH2-Trp-Val-Trp-Val-Trp-Val-Lys-Lys-COOH) has been introduced as a good candidate for modification of carbon nanotubes due to its high affinity toward the exterior surface of these nano-carriers. In order to optimize the process of SWCNT peptide functionalization, the effects of chirality and diameter of SWCNTs as well as the temperature on PW3 adsorption were systematically investigated using molecular dynamics (MD) simulation. It was found that modification of chiral/zigzag SWCN
Nanotechnology is developing rapidly for its ability to modify metals to nanosize which, in general, changes the physical, chemical and optical properties of metals. In this paper, the authors used local bacteria from a chromite mine in Sabzevar, Iran, for quick and environmentally friendly biosynthesis of functional silver nanoparticles (AgNPs). The results presented the efficient conditions for AgNP biosynthesis through reduction of silver ions by the supernatant of an Enterobacter sp. strain. After biosynthesis, the AgNPs were cleaned by centrifugation, and samples were further analyzed by ultraviolet–visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction and scanning electron microscopy. The refined AgNPs yielded the
The surface of nanoparticles (NPs) get coated by a wide range of biomolecules, upon exposure to biological fluids. It is now being increasingly accepted that NPs with particular physiochemical properties have a capacity to induce conformational changes to proteins and therefore influence their biological fates, we hypothesized that the gold NP’s metal surface may also be involved in the observed Fg unfolding and inflammatory response. To mechanistically test this hypothesis, we probed the interaction of Fg with gold surfaces using molecular dynamic simulation (MD) and revealed that the gold surface has a capacity to induce Fg conformational changes in favor of inflammation response. As the integrity of coatings at the surface of ultra-sma
Poly(amidoamine) (PAMAM) dendrimers are promising nanocarriers that can enhance the solubility of hydrophobic drugs. The surface chemistry of dendrimers is of great relevance as end groups of these nanocarriers can be easily modified to improve the bioavailability and sustained release of the cargo. Therefore, a molecular‐level understanding of the host‐guest interactions that can give both qualitative and quantitative information is particularly desirable. In this work, fully atomistic molecular dynamics simulations were used to study the association of a bioactive natural product, ie, chalcone, with amine‐, acetyl‐, and carboxyl‐terminated PAMAM dendrimers at physiological and acidic pH environments. Amine‐ and carboxyl‐ter
The present study aimed to evaluate a class of A-D-π-D-A organic dyes by replacing central π-spacer by fused electron rich(D) and electron deficient(A) moieties (D-A) with different configurations in order to shed light on the role of the structure of fused π-bridge on the cell performance. In addition, the effect of the structure of side chain on the N-atom of donor was investigated. The electronic and optical properties of the dyes and dye-TiO2 complexes, which are relevant to the short circuit photocurrent density and open circuit photovoltage, were comprehensively analyzed. The results indicated that the correct choice of side chain results in improving VOC while the molecular engineering of the side chain on the donor plays an insig
A series of experimentally synthesized metal free organic dyes based on the 2-Cyano-3-(5-(5′-(4-(diphenylamino) phenyl)-4, 4′-dihexyl-2, 2′-bithiazol-5-yl) thiophen-2-yl) acrylic acid (dye 1) were investigated, based on computational methods to shed light on how a tiny difference in π-linker of sensitizer, CC and thiophene moiety as the additional π spacer group in dyes 2 and 3 respectively, has a significant impact on the short-circuit photocurrent densities (J SC) in Dye-sensitized solar cells (DSSCs). Although dyes 2 and 3 have similar redshifts in comparison to dye 1 in the UV–vis absorption spectra, there is a significant difference between J SC values of these dyes resulting in different solar cell efficiency. To understand
This study explains some electronic and structural parameters of niacin (NA) encapsulation into PAMAM-G1 dendrimer using DFT calculations. Optimized structural geometries, interaction energies, NMR, NBO, and AIM analyses, in accordance with experiment, revealed that the stability of G1@NA complex can be attributed to the five intermolecular hydrogen bonds formed between the functional groups of G1 and NA. Because of nearing to the experimental results, all the calculations repeated again using a self-consistent reaction field (SCRF) and the polarizable continuum model (PCM) to address the implicit solvent effects and the obtained results were in line with the calculations in gas phase.
A series of experimentally synthesized metal free organic dyes based on the 2-Cyano-3-(5-(5′-(4-(diphenylamino)phenyl)-4,4′-dihexyl-2,2′-bithiazol-5-yl)thiophen-2-yl)acrylic acid (dye?1) were investigated, based on computational methods to shed light on how a tiny difference in π-linker of sensitizer, CC and thiophene moiety as the additional π spacer group in dyes 2 and 3 respectively, has a significant impact on the short-circuit photocurrent densities (JSC) in Dye-sensitized solar cells (DSSCs). Although dyes 2 and 3 have similar redshifts in comparison to dye 1 in the UV–vis absorption spectra, there is a significant difference between JSC values of these dyes resulting in different solar cell efficiency. To understand the ori
Characterization of the dimer interactions at the dimeric interface of the crystal structure of rice α-amylase/subtilisin inhibitor (RASI) were performed using the quantum theory of atoms in molecules (QTAIM) and natural bonding orbital (NBO) analyses at the density-functional theory (DFT) level. The results revealed that Gly27 and Arg151 of chain A are the main residues involved in hydrogen bonds, dipole-dipole, and charge-dipole interactions with Gly64, Ala66, Ala67 and Arg81 of chain B at the dimeric interface. Calcium ion of chain A plays the significant role in the stability of the dimeric structure through a strong charge-charge interaction with Ala66.
A fragment of Histidine rich protein II (HRP II 215-236) was investigated by 14N and 17O electric field gradient, EFG, tensor calculations using DFT. This study is intended to explore the differences between 310-helix and α-helix of HRPII both in the gas phase and in solution. To achieve the aims, the 17O and 14N NQR parameters of a fragment of HRPII (215-236) for both structures are calculated. Due to the side chain arrangements of the 310-helix, this conformation contains several hydrogen bonding contacts in comparison to the α-helix form. The resultant 14N and 17O s of peptide bonds of HRPII are affected by these contacts. Both in the gas phase and in solution, the differences in 14N s of backbone are within the uncertainties identical
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