The efficiency of pristine graphene (GN) in the delivery process of the Favipiravir (FPV) anti-COVID-19 drug was herein revealed within the FPV GN complexes in perpendicular and parallel ...configurations in terms of the density functional theory (DFT) method. Adsorption energy findings unveiled that the parallel configuration of FPV GN complexes showed higher desirability than the perpendicular one, giving adsorption energy up to −15.95 kcal mol
−1
. This favorability could be interpreted as a consequence of the contribution of π-π stacking to the overall strength of the adsorption process in the parallel configuration. Frontier molecular orbitals (FMO) findings demonstrated the ability of the GN nanosheet to adsorb the FPV drug by the alteration in the
E
HOMO
,
E
LUMO
, and
E
gap
values before and after the adsorption process. Based on Bader charge results, the FPV drug and GN sheet exhibited electron-donating and -accepting characters, respectively, which was confirmed by the negative sign of the computed charge transfer (
Q
t
) values. The FPV(R) T@GN complex showed the most desirable
Q
t
value of −0.0377
e
, which was in synoptic with the adsorption energy pattern. Electronic properties of GN were also altered after the adsorption of the FPV drug in both configurations, with more observable changes in the parallel one. Interestingly, the Dirac point of the GN sheet coincided with the Fermi level after the adsorption process, indicating that the adsorption process unaffected the presence of the Dirac point. The occurrence of the adsorption process was also noticed by the existence of new bands and peaks in the band structure and DOS plots, respectively. Short recovery time rendered the GN nanosheet an efficient FPV drug delivery system. The obtained findings provide new insight into the biomedical applications of the GN sheet as a promising drug delivery system.
The efficacy of the graphene nanosheet to adsorb Favipiravir drug candidate was investigated at various adsorption sites using DFT methods.
Graphene (GN) nanosheets have been widely exploited in biomedical applications as potential nanocarriers for various drugs due to their distinct physical and chemical properties. In this regard, the ...adsorption behavior of cisplatin (
PtCl
) and some of its analogs on a GN nanosheet was investigated in perpendicular and parallel configurations by using density functional theory (DFT). According to the findings, the most significant negative adsorption energies (
) within the
PtX
⋯GN complexes (where X = Cl, Br, and I) were observed for the parallel configuration, with values up to -25.67 kcal/mol at the H@GN site. Within the perpendicular configuration of the
PtX
⋯GN complexes, three orientations were investigated for the adsorption process, namely, X/X, X/NH
, and NH
/NH
. The negative
values of the
PtX
⋯GN complexes increased with the increasing atomic weight of the halogen atom. The Br@GN site showed the largest negative
values for the
PtX
⋯GN complexes in the perpendicular configuration. The Bader charge transfer outcomes highlighted the electron-accepting properties of
PtI
within the
PtI
⋯GN complexes in both configurations. The electron-donating character of the GN nanosheet increased as the electronegativity of the halogen atom increased. The band structure and density of state plots revealed the occurrence of the physical adsorption of the
PtX
on the GN nanosheet, which was indicated by the appearance of new bands and peaks. Based on the solvent effect outlines, the negative
values generally decreased after the adsorption process in a water medium. The recovery time results were in line with the
findings, where the
PtI
in the parallel configuration took the longest time to be desorbed from the GN nanosheet with values of 61.6 × 10
ms at 298.15 K. The findings of this study provide better insights into the utilization of GN nanosheets in drug delivery applications.
The potentiality of the β12 borophene (β12) and pristine graphene (GN) nanosheets to adsorb tetrahalomethanes (CX4; X = F, Cl, and Br) were investigated using density functional theory (DFT) methods. ...To provide a thorough understanding of the adsorption process, tetrel (XC-X3∙∙∙β12/GN)- and halogen (X3C-X∙∙∙β12/GN)-oriented configurations were characterized at various adsorption sites. According to the energetic manifestations, the adsorption process of the CX4∙∙∙β12/GN complexes within the tetrel-oriented configuration led to more desirable negative adsorption energy (Eads) values than that within the halogen-oriented analogs. Numerically, Eads values of the CBr4∙∙∙Br1@β12 and T@GN complexes within tetrel-/halogen-oriented configurations were −12.33/−8.91 and −10.03/−6.00 kcal/mol, respectively. Frontier molecular orbital (FMO) results exhibited changes in the EHOMO, ELUMO, and Egap values of the pure β12 and GN nanosheets following the adsorption of CX4 molecules. Bader charge transfer findings outlined the electron-donating property for the CX4 molecules after adsorbing on the β12 and GN nanosheets within the two modeled configurations, except the adsorbed CBr4 molecule on the GN sheet within the tetrel-oriented configuration. Following the adsorption process, new bands and peaks were observed in the band structure and density of state (DOS) plots, respectively, with a larger number in the case of the tetrel-oriented configuration than in the halogen-oriented one. According to the solvent effect affirmations, adsorption energies of the CX4∙∙∙β12/GN complexes increased in the presence of a water medium. The results of this study will serve as a focal point for experimentalists to better comprehend the adsorption behavior of β12 and GN nanosheets toward small toxic molecules.
The potentiality of the 6-mercaptopurine (
MP
) and 6-thioguanine (
TG
) expired drugs toward the corrosion inhibition of the aluminium
(Al) (111)
surface was widely investigated using a series of ...density functional theory (DFT) calculations. A competition between the anti-corrosive features of the studied drugs in the gas and aqueous phases was conducted on both neutral and protonated forms by means of quantum mechanical descriptors. The results of the electrostatic potential analysis demonstrated the prominent nucleophilic nature of the sulfur and nitrogen atoms over the structures of the examined drugs. The frontier molecular orbital theory findings outlined the higher preferability of
TG
over
MP
as a corrosion inhibitor. Upon determining the most beneficial configurations of the
MP/TG Al (111)
complexes, first-principles molecular dynamics simulations were executed. Interestingly, the competence of the
TG
drug in the corrosion inhibition process of
Al (111)
was more extensive than that of the
MP
one, which was confirmed by the interaction energy values of −1.79 and −1.64 eV, respectively. Upon obtaining the relaxed complexes, the effect of the presence of water solvent on the adsorption process was studied. These findings provide a foundation for developing green anti-corrosive inhibitors for the aluminium surface.
The efficiency of 6-mercaptopurine and 6-thioguanine expired drugs as corrosion inhibitors of aluminium surface was thoroughly assessed using DFT method.
Herein, the potentiality of carbon-containing molecules (W–C–F
3
, where W is a withdrawing atom or group) to interact with Lewis bases (B), Lewis acids (A) and σ–hole-containing molecules (X
2
) ...with W–C···B/A/X
2
angle of 180° was reported.
−
σ–hole and
+
σ–hole terminologies were implemented to describe the interactions of W–C–F
3
with nucleophilic and electrophilic sites, respectively. To characterize such interactions, quantum mechanical calculations including geometrical optimization,
±
σ–hole test, interaction energy calculation, quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) index calculation were performed at MP2/aug-cc-pVTZ(PP) level of theory. The results showed (1) the electrostatic potentiality of the W–C–F
3
molecules to favorably interact with Lewis bases and acids, (2) the dependency of
±
σ–hole interaction energies on the σ–hole size of the tetrel atom and (3) descending of interaction energies in the order W–C–F
3
···B > W–C–F
3
···X
2
> W–C–F
3
···A. QTAIM, and NCI calculations revealed the noncovalent nature of the
±
σ–hole interactions. Further, an investigation on F–C–X
3
model was carried out to highlight the emerging role of X
3
atoms in
±
σ–hole interactions. Comprising of the findings, the most favorable interaction energies were denoted when the F–C–X
3
interact with X
2
molecules compared to those with B and A molecules.
This study aimed to evaluate transdermal delivery of vancomycin hydrochloride using the combination of ethosomes as an encapsulating vesicle and iontophoresis. Ethosomes were prepared and evaluated ...in terms of electrochemical stability. Cathodal iontophoresis of negatively charged ethosomes and anodal iontophoresis of free drug solution and positively charged vesicles were conducted. The effect of current mode, density, concentration of drug and ionic strength was studied. In vivo study was performed by inducing mediastinitis in Sprague-Dawley rats using methicillin-resistant Staphylococcus aureus as infected pathogen, the mean bacterial count was compared between groups of rats, one of the treated groups received drug intramuscularly while the other group received vancomycin using iontophoretic delivery of optimized ethosomal formula. Ethosomes showed efficient electrochemical stability, cathodal iontophoresis of negatively charged vesicle (F2) showed maximum transdermal flux (550 µg/cm
2
/h) compared to free drug solution and other ethosomal formulae, transdermal flux was reduced by altering current mode from continuous to ON/OFF mode, reducing current density and by using normal saline as drug solvent; on the other hand, flux was potentiated by increasing drug concentration from 25 to 75 mg/ml. In vivo study revealed that there was a significant difference in terms of bacterial count between untreated and treated groups, while there was no statistically significant difference between the I.M. vancomycin treatment and treatment conducted by iontophoretic delivery of vancomycin encapsulated in ethosomal formula. Combination between ethosomes and iontophoresis had succeeded in delivering vancomycin transdermally.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The versatility of striped borophene (sB),
borophene (
), and pristine graphene (GN) to adsorb π-systems was comparatively assessed using benzene (BNZ) and hexafluorobenzene (HFB) as electron-rich ...and electron-deficient aromatic π-systems, respectively. Using the density functional theory (DFT) method, the adsorption process of the π-systems on the investigated 2D sheets in the parallel configuration was observed to have proceeded more favorably than those in the vertical configuration. According to the observations of the Bader charge transfer analysis, the π-system∙∙∙sB complexes were generally recorded with the largest contributions of charge transfer, followed by the π-system∙∙∙
and ∙∙∙GN complexes. The band structures of the pure sheets signaled the metallic and semiconductor characters of the sB/
and GN surfaces, respectively. In the parallel configuration, the adsorption of both BNZ and HFB showed more valence and conduction bands compared to the adsorption in the vertical configuration, revealing the prominent preferentiality of the anterior configuration. The density-of-states (DOSs) results also affirmed that the adsorption process of the BNZ and HFB on the surface of the investigated 2D sheets increased their electrical properties. In all instances, the sB and
surfaces demonstrated higher adsorptivity towards the BNZ and HFB than the GN analog. The findings of this work could make a significant contribution to the deep understanding of the adsorption behavior of aromatic π-systems toward 2D nanomaterials, leading, in turn, to their development of a wide range of applications.
The adsorption of toxic carbon dichalcogenides (CX2; X = O, S, or Se) on β12 borophene (β12) and pristine graphene (GN) sheets was comparatively investigated. Vertical and parallel configurations of ...CX2⋯β12/GN complexes were studied herein via density functional theory (DFT) calculations. Energetic quantities confirmed that the adsorption process in the case of the parallel configuration was more desirable than that in the vertical analog and showed values up to −10.96 kcal/mol. The strength of the CX2⋯β12/GN complexes decreased in the order CSe2 > CS2 > CO2, indicating that β12 and GN sheets showed significant selectivity for the CSe2 molecule with superb potentiality for β12 sheets. Bader charge transfer analysis revealed that the CO2⋯β12/GN complexes in the parallel configuration had the maximum negative charge transfer values, up to −0.0304 e, outlining the electron-donating character of CO2. The CS2 and CSe2 molecules frequently exhibited dual behavior as electron donors in the vertical configuration and acceptors in the parallel one. Band structure results addressed some differences observed for the electronic structures of the pure β12 and GN sheets after the adsorption process, especially in the parallel configuration compared with the vertical one. According to the results of the density of states, new peaks were observed after adsorbing CX2 molecules on the studied 2D sheets. These results form a fundamental basis for future studies pertaining to applications of β12 and GN sheets for detecting toxic carbon dichalcogenides.
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•Corrosion inhibition efficiency of barbituric acid and its thio derivatives toward aluminium surface is elucidated.•Molecular dynamics simulations are executed for ...inhibitor∙∙∙aluminium (Al)(111) complexes.•Binding energy affirmations proclaim increasing the inhibition efficiency in the order BA∙∙∙ < 1S∙∙∙ < 2S∙∙∙ < 3S∙∙∙Al.•Global and local reactivity parameters affirm the further favorability of 3S compound over other studied analogs.
The corrosion inhibition efficiency of the barbituric acid and its thio derivatives were herein monitored by the execution of a variety of density functional theory (DFT) computations. The 1,3-diazinane-2,4,6-trione (BA); 6-sulfanylidene-1,3-diazinane-2,4-dione (1S); 2,6-bis(sulfanylidene)-1,3-diazinan-4-one (2S); and 1,3-diazinane-2,4,6-trithione (3S) compounds were devoted as aluminum corrosion inhibitors. Global and local quantum descriptors were determined for the neutral and protonated forms of the modelled inhibitors in gas and aqueous phases. As the global indices indicated, reverse and proportional correlations were noticed between the number of S atoms in the studied inhibitors and their ionization potential and electron affinity. Accordingly, the inhibition efficiency of the studied compounds generally increased in the order BA < 1S < 2S < 3S. In the same line, the obtained values of local nucleophilic and electrophilic Fukui function indices affirmed the further favorability of the 3S compound over other studied analogs. Utilizing molecular dynamics simulations, the most favorable configurations for inhibitor∙∙∙aluminium (Al)(111) complexes were characterized. Binding energy calculations revealed the efficiency of the corrosion inhibition increased in the order BA∙∙∙Al (−0.95 eV) < 1S∙∙∙Al (−1.71 eV) < 2S∙∙∙Al (−2.16 eV) < 3S∙∙∙Al (−2.49 eV). Upon the presented findings, the current work would be a sufficient linchpin for future research related to the aluminium corrosion inhibition process, particularly with the incorporation of acids and their thio derivatives.
The potentiality of the βsub.12 borophene (βsub.12) and pristine graphene (GN) nanosheets to adsorb tetrahalomethanes (CXsub.4; X = F, Cl, and Br) were investigated using density functional theory ...(DFT) methods. To provide a thorough understanding of the adsorption process, tetrel (XC-Xsub.3∙∙∙βsub.12/GN)- and halogen (Xsub.3C-X∙∙∙βsub.12/GN)-oriented configurations were characterized at various adsorption sites. According to the energetic manifestations, the adsorption process of the CXsub.4∙∙∙βsub.12/GN complexes within the tetrel-oriented configuration led to more desirable negative adsorption energy (Esub.ads) values than that within the halogen-oriented analogs. Numerically, Esub.ads values of the CBrsub.4∙∙∙Br1@βsub.12 and T@GN complexes within tetrel-/halogen-oriented configurations were −12.33/−8.91 and −10.03/−6.00 kcal/mol, respectively. Frontier molecular orbital (FMO) results exhibited changes in the Esub.HOMO, Esub.LUMO, and Esub.gap values of the pure βsub.12 and GN nanosheets following the adsorption of CXsub.4 molecules. Bader charge transfer findings outlined the electron-donating property for the CXsub.4 molecules after adsorbing on the βsub.12 and GN nanosheets within the two modeled configurations, except the adsorbed CBrsub.4 molecule on the GN sheet within the tetrel-oriented configuration. Following the adsorption process, new bands and peaks were observed in the band structure and density of state (DOS) plots, respectively, with a larger number in the case of the tetrel-oriented configuration than in the halogen-oriented one. According to the solvent effect affirmations, adsorption energies of the CXsub.4∙∙∙βsub.12/GN complexes increased in the presence of a water medium. The results of this study will serve as a focal point for experimentalists to better comprehend the adsorption behavior of βsub.12 and GN nanosheets toward small toxic molecules.
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