Extensive urbanization has greatly raised the demand for cleaner coal- and petroleum-derived fuels. Mainly composed of methane, natural gas represents a promising alternative for this purpose, making its storage a significant topic. In the present research, deposition of methane molecules in C60 fullerene was investigated through a combined approach wherein density functional based tight binding (DFTB) method was used to optimize the geometry while ab initio density functional theory (DFT) served as a tool for energy calculation. Doping endohedral methane molecules onto fullerene nanocage, it was witnessed that, the only stable complex might be formed by a single methane molecule entrapped inside the C60 cage. It was further indicated that, when a large number of encapsulated CH4 molecules are concerned, occasional chemisorption of the molecules on the inner surface of the cage would occur, ending up breaking the capsule side wall at NCH4=7. Further studied by density-functional tight-binding molecular dynamics (DFTB-MD) simulation, mechanism of the breakage indicated this complex as being highly unlikely to be stable. Manuscript profile

The interaction between nanoparticles and biomolecules such as protein and DNA is one of the major instructions of nanobiotechnology research. In this study, we have explored the interaction of adenine nucleic base with a representative golden cluster (Au13) by using dispersion corrected density functional theory (DFT-D3) within GGA-PBE model of theory. Various active sites as and ways of approach as well as several affecting parameters on the interaction nature of interacting molecules such as adsorption energy, binding distance, solvent effect and, electronics structure were investigated. Our first-principles results indicated that adenine forms a stable complex with the golden cluster with interaction energy of –42.84 kcal/mol and binding distance of 2.139 Å. Charge transfer analysis with Hirshfeld approach demonstrated about 0.52 e was transferred from adenine to golden cluster skeleton. It was found from the obtained interaction parameters that there is strong interaction (chemisorption) between adenine and golden cluster. The type and strength of interaction have been also confirmed by hybrid functional B3LYP level of theory. This finding is very promising for potential medicinal and pharmaceutical applications of golden clusters. Manuscript profile

In this study, Sr Gdx Fe(12 –x) O19 nanostructures (x= 0, 0.2(3% Gd), 0.4 (6%Gd),0.6(9%Gd), 0.8 (12%Gd)) were synthesized by self-combustion sol-gel method and then calcined at the temperature of for 3 h. This compound was then composited with functionalized graphene oxide (GO) for the photocatalytic degradation of Enrofeloxacin. FESEM, EDS, XRD, and FTIR analysis were employed to investigate the particle size, elemental composition, morphological structure, functional groups determination and structural composition of the samples. VSM, BET-BJH, TGA-DTA, DRS and zeta potential analysis were also used to assess the magnetic properties, surface area, thermal stability, band-gap determination and suspension stability of the specimens, respectively. For evaluation of performance, photocatalytic degradation of Enrofeloxacin (an antibiotic that is widely used for domestic animals) is performed. The results showed that the 3% and 6% Gd-doped composites had the highest efficiencies in the photocatalytic reaction.This research reports the successful synthesis of SrGdxFe12-xO19/GO-COOH composites and its characterization by various techniques. The results indicated that SrGdxFe12-xO19/GO-COOH composite can be employed as an applicable candidate for the photodegradation of ENR antibiotic drug from pharmaceutical industry effluent as well as the water resources. Analysis of the results by statistical software based on the response surface method showed that the prolongation of the radiation time and catalyst mass, as well as pH reduction, can enhance the efficiency of ENR photodegradation. By increasing the pollutant concentration, however, the degradation efficiency declined. Manuscript profile

The interaction between nanoparticles and biomolecules such as protein andDNA is one of the major instructions of nanobiotechnology research. In this study,we have explored the interaction of adenine nucleic base with a representativegolden cluster (Au13) by using dispersion corrected density functional theory(DFT-D3) within GGA-PBE model of theory. Various active sites as and ways ofthe approach as well as several affecting parameters on the interaction nature ofinteracting molecules such as adsorption energy, binding distance, solvent effectand, electronics structure were investigated. Our first-principles results indicatedthat adenine forms a stable complex with the golden cluster with interactionenergy of –42.84 kcal/mol and binding distance of 2.139 Å. Charge transferanalysis with Hirshfeld approach demonstrated about 0.52 e was transferred fromadenine to golden cluster skeleton. It was found from the obtained interactionparameters that there is strong interaction (chemisorption) between adenine andgolden cluster. The type and strength of interaction have been also confirmed byhybrid functional B3LYP level of theory. This finding is very promising for potentialmedicinal and pharmaceutical applications of golden clusters. Manuscript profile

Hydrogen storage capacity of Si-coated B80 fullerene was investigated based on density functional theory calculations within local density approximation and generalized gradient approximation. It is found that Si atom prefer to be attached above the center of pentagon with a binding energy of -5.78 eV. It is inferred that this binding is due to the charge transfer between the Si atom and B80 cage, such as B80AM, B80Ca and B80Mg complexes. The media produced by 12 Si atoms coating on B80, i.e. Si12B80, which Si atoms do not cluster on the B80 surface, can store up to 96 hydrogen molecules resulting in the gravimetric density of 13.87 wt %. Binding of 96 H2 molecules adsorbed on Si12B80 is found to be -0.03 eV/H2 based on the first-principles van der Waals density functional calculations being an indication of the weak interaction (physisorption) between H2 molecules and B80. Furthermore, the adsorption behavior of 96 H2 molecules around the Si12B80 complex was studied through ab initio molecular dynamics simulation at room temperature. Our finding shows that hydrogen molecules escape from the cage, which highlights that the corresponding system easily releases the hydrogen molecules at ambient conditions. Manuscript profile

The present work was an attempt to evaluate the potentialities of using SWCNTs as nanovectors for drug delivery of anticancer drug Oxaliplatin. First-principles van der Waals density functional (vdW-DF) calculations are used to investigate the incorporation of oxaliplatin inside the typical semiconducting and metallic single wall carbon nanotubes with various diameters (SWCNTs). Adsorption energy is calculated and the results show that oxaliplatin affinity for the semiconducting SWCNTs is stronger than that for the metallic counterparts. The obtained binding energies reveal that oxaliplatin prefers to be encapsulated into the semiconducting and metallic nanotubes with diameter of about 9 and 11 Å, respectively. We also found that vdW forces mainly contribute to the binding of selected drug molecule to SWCNTs. The study of the electronic structures and charge analysis indicate that no significant hybridization between the respective orbital takes place and the small interaction obtained quantitatively in terms of binding energies. Our findings afford not only a molecular insight into understanding of the interaction between oxaliplatin and SWCNTs but also may be instructive to relevant scientists who are attempt to develop effective methods for suitable nanovectors for drug delivery. Manuscript profile

The interaction between drugs and nanostructured materials such as nanotubes is proving to be of fundamental interest for drug delivery and nanobiosensing. In the present work, the interaction of Fluorouracil, as an anticarcinogenic drug, with pristine CNT and Pt-doped CNT was investigated at the B3LYP-D3/TZVP level. Full optimization procedure has been carried out for all interacting systems to better understand the trends in binding nature of drug molecule interacting with the selected nanocarrier. We have evaluated the various stable configurations at both gas phase and aqueous solution for the considered complexes based on their interaction nature. Calculated adsorption energies indicated that Fluorouracil can form stable binding with Pt-CNT in aqueous media with adsorption energy of −1.12 eV which was found to be a chemisorption process. Charge analysis revealed that, upon binding of Fluorouracil to the nanocarrier, the overall charge on the host and guest systems changes and significant charges have been transferred from Fluorouracil to the substrates. Quantum molecular descriptors calculations also demonstrate the significant changes in the electronic properties of the nanostructures due to the Fluorouracil attachment. Interaction between Fluorouracil and pristine CNT however has been found to be typical for the physisorption with adsorption energy of about −0.405 eV. Our findings offer fundamental insights into the functionalization of the Pt-doped CNT and envisage the applicability of these nanostructured materials as a novel drug delivery vehicle for the transportation of anticarcinogenic drug within thetarget cells. Manuscript profile