scholarly journals SWCNTs Interaction with Dopamine and Serotonin Anticancer Through QM/MM Methods: A Drug Delivery Approaches

2021 ◽  
Vol 14 (2) ◽  
pp. 173-179
Author(s):  
Nastaran Saghayi Marouf ◽  
Majid Monajjemi ◽  
Karim Zare ◽  
Ali Shamel

Objetive: Dopamine and Serotonin are the two important biological transmitters that have hormonal activities and responsible for happiness and felling well. The aim of this article was to study theoretically the structure features of Dopamine and Serotonin in the complex of single-walled carbon nanotube as a neurotransmitter. Material and Methods: The structure of Dopamine and Serotonin binding with SWCNT with four different diameters (7.0,7.5,7.7,10.0 nm) was studied by using molecular mechanic (MM) and quantum mechanic (QM). The remarkable energies including potential energy, total energy and kinetic energy in time of simulation 10 ns steps in two temperatures (298, 310 kelvin degree) were investigated by Monte Carlo method with opls force filed. NMR shielding tensor data by B3LYP level of theory with 6-31 G(d) as a basis set and semi empirical method have been also fulfilled. Results: Theoretical computations were performed to study NMR chemical shift data including magnetic shielding tensor (σ, ppm), shielding asymmetry (η), magnetic shielding anisotropy (σaniso), magnetic shielding isotropy (σiso) , skew of a tensor (Κ) and chemical shift anisotropy (Δσ) and span (Ω) at various rotation angles around a specific rotation, physical and chemical properties of atomic nuclei. Semi empirical calculations such as total energy, binding energy, isolated atomic energy, electronic energy, core–core interaction and heat of formation in AM1 were revealed. Conclusion: It is figured out in Monte Carlo method our two specific drug and its nanotube with small diameter are the most stable one than the others. The larger diameter leads the combination stability into lower value.

2021 ◽  
Vol 34 (02) ◽  
pp. 776-789
Author(s):  
Nastaran Saghayimarouf ◽  
Majid Monajjemi ◽  
Karim Zare ◽  
Ali Shamel

Carbon nano tubes (CNTS) have two basic structure as single-walled and multi-walled based on hexagonal plexus of carbon atoms. CNTs can serve as platforms to conjugate other compounds specially in medications purposes by immobilization of biomolecules at their surface. Dopamine and serotonin are two biological molecules which have bifunctional activities as hormone and neurotransmitter. These two molecules have important roles as neurotransmitters in the central and peripheral nervous systems but serotonin functions as a mood regulator, while dopamine is connected to the “pleasure center”. In this article we optimized molecular and structural properties of connected dopamine and serotonin with SWNTS with four different diameters (7.0,7.5,7.7 and 10.0 nm) by using molecular quantum methods such as NMR shielding tensor data by B3LYP level of theory with 6-31 G(d) as a basis set, mk and frequency methods. Theoretical computations were performed to study NMR chemical shift data including magnetic shielding tensor (σ, ppm), shielding asymmetry (η), magnetic shielding anisotropy (σaniso), magnetic shielding isotropy (σiso) , skew of a tensor (Κ) and chemical shift anisotropy (Δσ) and span (Ω) at various rotation angles around a specific rotation  , physical and chemical properties of atomic nuclei , frequency data  by B3LYP/6-31g level of theory and POP method using gaussian 09 program.


2020 ◽  
Vol 33 (01) ◽  
pp. 94-108
Author(s):  
Mina Zakeri ◽  
Majid Monajjemi ◽  
Ali Ebrahimi

In this article, we discussed about four antihistamine drug called promethazine, loratadine, cetirizine and buclizine. Promethazine in this list is the only one in first generation antihistamine classification with CNS sedation effect and the other three belongs to second generation antihistamine group which are non-sedation and used to treat in many different anti-allergenic fields. In the following we optimized potential, kinetic and total energy of these molecules at body temperature (310 k˚) and environment temperature (298 k ˚) using Mont Carlo method in Amber force field in 500 ns. The quantum mechanics calculations and molecular structure of these molecules investigated using B3LYP level of theory with 6-31 G (d) as a basis set. Theoretical computations were performed to study thermodynamic parameters and frequency analysis. Electronic, thermal, zero point and gibs free energy and enthalpy were estimated in frequency analysis. Semi empirical computations were summarized to pm3 method and different energy parameters (total energy, Binding Energy, Isolated Atomic Energy, Electronic Energy, Core–Core Interaction and Heat of Formation.


2009 ◽  
Vol 87 (1) ◽  
pp. 348-360 ◽  
Author(s):  
Bryan A Demko ◽  
Roderick E Wasylishen

A 31P and 77Se solid-state NMR investigation of the iminobis(diorganophosphine chalcogenide) HN(R2PE)2 (R = Ph,iPr; E = O, S, Se) systems is presented. The NMR results are discussed in terms of the known HN(R2PE)2 structures available from X-ray crystallography. The phosphorus chemical shift tensors are found to be sensitive to the nature of the alkyl and chalcogen substituents. The nature of the R group also influences the selenium chemical shift tensors of HN(R2PSe)2 (R = Ph, iPr), which are shown to be sensitive to hydrogen bonding in the dimer structure of HN(Ph2PSe)2 and to the presence of disorder in the case of HN(iPr2PSe)2. Scalar relativistic ZORA DFT nuclear magnetic shielding tensor calculations were performed yielding the orientations of the corresponding chemical shift tensors. A theoretical investigation into the effect of the E-P···P-E “torsion” angle on the phosphorus and selenium chemical shift tensors of a truncated HN(Me2PSe)2 system indicates that the electronic effect of the alkyl group on the respective nuclear magnetic shielding tensors are more important than the steric effect of the E-P···P-E torsion angle.Key words: iminobis(diorganophosphine chalcogenide), solid-state NMR, 31P NMR, 77Se NMR, ZORA DFT.


2020 ◽  
Vol 225 ◽  
pp. 10003
Author(s):  
G. de Izarra ◽  
M. Lamotte ◽  
S. Bréaud ◽  
A. Pépino ◽  
P. Filliatre ◽  
...  

Since a few years, simulation codes were built at CEA Cadarache to predict the signal of ionisation chambers and taylor detectors for specific applications. It is proposed here to present COSICAF, a tool developed for mainly academic purpose and rapid fission chamber prototyping. This numerical simulation, mostly based on semi-empirical models and Monte-Carlo method will help students to understand how ionisation chambers work. Through the paper, models and their numerical implementation will be discussed. A focus is made on recently implemented features like charge multiplication and correlated source which make the simulation of proportional counter possible. To demonstrate the interest of the code, simulations of a planar fission chamber is proposed.


1975 ◽  
Vol 30 (1) ◽  
pp. 83-86 ◽  
Author(s):  
Chiara Margheritis ◽  
Cesare Sinistri

Abstract Molten CsBr was computer simulated tat 1 atm and four different temperatures using the Monte Carlo method. Structural and thermodynamic properties of the melt were obtained on the basis of pair potentials. In particular, radial distribution functions, volume, and energy with its coulomb, dipole-dipole, and repulsive components were determined. Separately, the polarization energy was also evaluated: this quantity increases with increasing temperature and ranges between 2 and 4% of the total energy.


2008 ◽  
Vol 07 (06) ◽  
pp. 1215-1225 ◽  
Author(s):  
LILIAN BERLU ◽  
HASSAN SAFOUHI

The present work concerns the analytical and numerical development of three-center molecular integrals over Slater-type functions (STFs) and B functions of the second order involving [Formula: see text] in the operator. These integrals appear in the analytic expression of the nuclear magnetic shielding tensor. The basis set of STFs is used to represent atomic orbitals. These STFs are expressed in terms of B functions, which are better suited to apply the Fourier transform method thoroughly developed by Steinborn group. Analytic expressions are obtained for the integrals of the second order involved in nuclear magnetic resonance shielding tensor over B functions. These expressions turned out to be similar to those obtained for the usual molecular multi-center integrals. Consequently, the numerical evaluation of the integrals under consideration will benefit from the work previously done on the molecular multi-center integrals.


2002 ◽  
Vol 01 (02) ◽  
pp. 295-308 ◽  
Author(s):  
LAETITIA VIEILLE ◽  
LILIAN BERLU ◽  
BRUNO COMBOURIEU ◽  
PHILIP HOGGAN

An accurate and rapid quantum chemistry approach to predicting chemical shifts is applied to 15 N natural abundance NMR spectra of benzothiazoles. This method is of interest in the study of toxic contaminants of biological media. A GIAO approach is used to calculate the nuclear shielding tensor in a perturbational scheme. Similar methods had previously been used for both ab initio and semi-empirical calculations programmed in Gaussian and MOPAC respectively but atomic orbitals specific to molecular sites are shown to improve accuracy in the present work. Some molecular sites are defined in order to polarize the molecular orbitals in the presence of the solvent interactions. For convenience, the extensions are carried out in an independent NMR module designed to work with the MOPAC package and the present application is generalized to the third row elements for the first time. This new theoretical work is described. The application to 15 N chemical shifts for benzothiazoles led to results within 0.5 ppm of values measured in this work. Structural investigations were carried out using the Gaussian98 suite of programs at the DFT B3LYP level of calculation over an extended basis set. These studies show the single chemical shift for benzothiazoles could be the result of rapid tautomeric equilibria. Further investigations show that solvent interactions involving hydrogen bonds should also be taken into account.


1974 ◽  
Vol 22 ◽  
pp. 307 ◽  
Author(s):  
Zdenek Sekanina

AbstractIt is suggested that the outbursts of Periodic Comet Schwassmann-Wachmann 1 are triggered by impacts of interplanetary boulders on the surface of the comet’s nucleus. The existence of a cloud of such boulders in interplanetary space was predicted by Harwit (1967). We have used the hypothesis to calculate the characteristics of the outbursts – such as their mean rate, optically important dimensions of ejected debris, expansion velocity of the ejecta, maximum diameter of the expanding cloud before it fades out, and the magnitude of the accompanying orbital impulse – and found them reasonably consistent with observations, if the solid constituent of the comet is assumed in the form of a porous matrix of lowstrength meteoric material. A Monte Carlo method was applied to simulate the distributions of impacts, their directions and impact velocities.


Author(s):  
Makoto Shiojiri ◽  
Toshiyuki Isshiki ◽  
Tetsuya Fudaba ◽  
Yoshihiro Hirota

In hexagonal Se crystal each atom is covalently bound to two others to form an endless spiral chain, and in Sb crystal each atom to three others to form an extended puckered sheet. Such chains and sheets may be regarded as one- and two- dimensional molecules, respectively. In this paper we investigate the structures in amorphous state of these elements and the crystallization.HRTEM and ED images of vacuum-deposited amorphous Se and Sb films were taken with a JEM-200CX electron microscope (Cs=1.2 mm). The structure models of amorphous films were constructed on a computer by Monte Carlo method. Generated atoms were subsequently deposited on a space of 2 nm×2 nm as they fulfiled the binding condition, to form a film 5 nm thick (Fig. 1a-1c). An improvement on a previous computer program has been made as to realize the actual film formation. Radial distribution fuction (RDF) curves, ED intensities and HRTEM images for the constructed structure models were calculated, and compared with the observed ones.


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