Si-doped phagraphene as a drug carrier for adrucil anti-cancer drug: DFT studies

Effect of functionalization on the adsorption performance of carbon nanotube as a drug delivery system for imatinib: molecular simulation study

In this study, efficiency of functionalized carbon nanotube as a potential delivery system for imatinib anti-cancer drug was investigated. Accordingly, carboxyl and hydroxyl functionalized carbon nanotube were inspected as a notable candidate for the carriage of this drug in aqueous media. For this purpose, possible interactions of imatinib with pure and functionalized carbon nanotube were considered in aqueous media. The compounds were optimized in gas phase using density functional calculations. Solvation free energies and association free energies of the optimized structures were then studied by Monte Carlo simulation and perturbation method in water environment. Outcomes of quantum mechanical calculations presented that pure and functionalized carbon nanotubes can act as imatinib drug adsorbents in gas phase. However, results of association free energy calculations in aqueous solution indicated that only carboxyl and hydroxyl functionalized carbon nanotubes could interact with imatinib. Monte Carlo simulation results revealed that electrostatic interactions play a vital role in the intermolecular interaction energies after binding of drug and nanotube in aqueous solution. Computed solvation free energies in water showed that the interactions with functionalized carbon nanotubes significantly enhance the solubility of imatinib, which could improve its in vivo bioavailability.

A dispersion-corrected DFT calculation on encapsulation of favipiravir drug used as antiviral against COVID-19 into carbon-, boron-, and aluminum-nitride nanotubes for optimal drug delivery systems combined with molecular docking simulations

Favipiravir (FAV) (6-fluoro-3-oxo-3,4-dihydropyrazine-2-carboxamide) is one of the most effective antiviral drugs which is cited for action against RNA-viral infections of COVID-19. In this study, density functional theory (DFT) calculations were used to investigate three nanotubes (NTs) with FAV drug as delivery systems. The encapsulated systems (ESs) consist of FAV drug inside carbon-carbon, aluminum nitride, and boron nitride. At B3LYP-D/6-31G(d,p) and CPCM/B3LYP-D/6-31G(d,p), the optimization of NTs, FAV, and its tautomeric forms and six ESs was investigated in gas and water environments. Five tautomeric forms of FAV were investigated, two keto forms (K1 and K2) and three enol forms (E1, E2, and E3). The results revealed that E3 and K2 isomeric forms represented the most stable structures in both media; thus, these two forms were encapsulated into the NTs. The stability and the synthesis feasibility of NTs have been proven by calculating their interaction energies. Non-covalent interactions (NCIs) were investigated in the ESs to show the type of NCI with the molecular voids. The binding energies, thermochemical parameters, and recovery times were investigated to understand the mechanism of FAV encapsulation and release. The encapsulated AlNNT systems are more favorable than those of BNNTs and CNTs in gas and aqueous environments with much higher binding energies. The quantum theory of atoms in molecules (QTAIM) and recovery time analysis revealed the easier releasing of E3 from AlNNT over K2 form. Based on molecular docking simulations, we found that E3 and K2 FAV forms showed a high level of resistance to SARS-CoV-6M3M/6LU7/6W9C proteases.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11224-023-02182-4.

Interaction of 5-Fluorouracil on the Surfaces of Pristine and Functionalized Ca12O12 Nanocages: An Intuition from DFT

The utilization of nanostructured materials for several biomedical applications has tremendously increased over the last few decades owing to their nanosizes, porosity, large surface area, sensitivity, and efficiency as drug delivery systems. Thus, the incorporation of functionalized and pristine nanostructures for cancer therapy offers substantial prospects to curb the persistent problems of ineffective drug administration and delivery to target sites. The potential of pristine (Ca₁₂O₁₂) and formyl (-CHO)- and amino (-NH₂)-functionalized (Ca₁₂O₁₂-CHO and Ca₁₂O₁₂-NH₂) derivatives as efficient nanocarriers for 5-fluorouracil (5FU) was studied at the B3LYP-GD3(BJ)/6-311++G(d,p) theoretical level in two electronic media (gas and solvent). To effectively account for all adsorption interactions of the drug on the investigated surfaces, electronic studies as well as topological analysis based on the quantum theory of atoms in molecules (QTAIM) and noncovalent interactions were exhaustively utilized. Interestingly, the obtained results divulged that the 5FU drug interacted favorably with both Ca₁₂O₁₂ and its functionalized derivatives. The adsorption energies of pristine and functionalized nanostructures were calculated to be -133.4, -96.9, and -175.6 kcal/mol, respectively, for Ca₁₂O₁₂, Ca₁₂O₁₂-CHO, and Ca₁₂O₁₂-NH2. Also, both topological analysis and NBO stabilization analysis revealed the presence of interactions among O₃-H₃₂, O₂₇-C₂₄, O₁₀-C₂₇, and N₂₄-H₃₂ atoms of the drug and the surface. However, 5FU@Ca₁₂O₁₂-CHO molecules portrayed the least adsorption energy due to considerable destabilization of the molecular complex as revealed by the computed deformation energy. Therefore, 5FU@Ca₁₂O₁₂ and 5FU@Ca₁₂O₁₂-NH₂ acted as better nanovehicles for 5FU.

Therapeutic potential of oxo-triarylmethyl (oxTAM) as a targeted drug delivery system for nitrosourea and fluorouracil anticancer drugs; A first principles insight

In this study, oxygenated triarylmethyl (oxTAM) is investigated by DFT calculations as a drug carrier framework for Nitrosourea (NU) and Fluorouracil (FU) drugs. Based on the adsorption analysis i.e., energies and distances between interacting atoms, it is found that oxTAM exhibits excellent carrier abilities for the delivery of FU (-1.53 eV & 2.00 Å) and NU (-1.33 eV & 2.12 Å) drugs. NCI and QTAIM results indicate the presence of hydrogen bonding in drug-carrier complexes. The values of dipole moment and global chemical descriptors show the significant reactivity of oxTAM for NU and FU drugs. Based on electronic property analysis, FU@oxTAM has a higher adsorption trend for complexation with oxTAM as compared to NU@oxTAM. Moreover, FU can easily release from the carrier due to the decreasing adsorption stability after protonation under an acidic environment as well as a short recovery time observed for the oxTAM carrier surface. Keeping in view all the above parameters, we inferred that oxTAM can serve as a potential drug delivery system for anticancer drugs including, Nitrosourea and Fluorouracil drugs.

Density Functional Theory Interaction Study of a Polyethylene Glycol-Based Nanocomposite with Cephalexin Drug for the Elimination of Wound Infection

In this paper, density functional theory (DFT) simulations are used to evaluate the possible use of a graphene oxide-based poly(ethylene glycol) (GO/PEG) nanocomposite as a drug delivery substrate for cephalexin (CEX), an antibiotic drug employed to treat wound infection. First, the stable configuration of the PEGylated system was generated with a binding energy of -25.67 kcal/mol at 1.62 Å through Monte Carlo simulation and DFT calculation for a favorable adsorption site. The most stable configuration shows that PEG interacts with GO through hydrogen bonding of the oxygen atom on the hydroxyl group of PEG with the hydrogen atom of the carboxylic group on GO. Similarly, for the interaction of the CEX drug with the GO/PEG nanocomposite excipient system, the adsorption energies are computed after determining the optimal and thermodynamically favorable configuration. The nitrogen atom from the amine group of the drug binds with a hydrogen atom from the carboxylic group of the GO/PEG nanocomposite at 1.75 Å, with an adsorption energy of -36.17 kcal/mol, in the most stable drug-excipient system. Drug release for tissue regeneration at the predicted target cell is more rapid in moist conditions than in the gas phase. The solubility of the suggested drug in the aqueous media around the open wound is shown by the magnitude of the predicted solvation energy. The findings from this study theoretically validate the potential use of a GO/PEG nanocomposite for wound treatment application as a drug carrier for sustained release of the CEX drug.

Theoretical study of glycoluril by highly symmetrical magnesium oxide Mg12O12 nanostructure: adsorption, detection, SERS enhancement, and electrical conductivity study

Using metal substrates that are nanoscale in size, surface-enhanced Raman scattering (SERS) is a technique for enhancing the Raman signal of biomolecules. Numerous industries including sensing materials, adsorption and medical devices, use nanomaterials like nanocages and nanoclusters. To discover a possible novel sensor platform involving a small metal cluster and a curved rigid substrate, we used density functional theoretical (DFT) simulations to explore the adsorption of glycoluril (GLC), a prospective drug intermediate, on a pure magnesium oxide cage (Mg₁₂O₁₂). This well defined cage was used as (i) an exact probable structure that could be used as well as (ii) a general model for MgO nanostructures. We also investigated the mono Al-doped Mg₁₂O₁₂ nanocage version Mg₁₁AlO₁₂. All computations were performed at the M06-2X level of theory. The GLC binds to the Mg₁₂O₁₂ nanocage by way of strong donor-acceptor interactions. The adsorption is releasing - 45.80 kcal mol^-1 of energy. Due to Al doping, the energy gap of GLC-Mg₁₁AlO₁₂ (1.91 eV) is reduced from that of GLC-Mg₁₂O₁₂ (4.28 eV) and hence there is an increase in electrical conductivity of GLC-Mg₁₁AlO₁₂. The electronic change in the nanocage's conductivity can be transformed into an electrical signal which can be used to detect the presence of the drug analyte. In addition, when a GLC molecule is present, the work function of the nanocage is also reduced. The MgO nanocage, we conclude, is a work function type as well as a possible electronic sensor for GLC drug detection. GLC desorption from the Mg₁₁AlO₁₂ surface recovers more quickly in comparison with Mg₁₂O₁₂ recovery time. The AIM and NCIs assessed in this study were performed to help analyze the electronic structures of the complexes. Our findings pave the possibility for Mg₁₁AlO₁₂ nanostructures to be used in drug recognition.

Application of DFT Calculations in Designing Polymer-Based Drug Delivery Systems: An Overview

Drug delivery systems transfer medications to target locations throughout the body. These systems are often made up of biodegradable and bioabsorbable polymers acting as delivery components. The introduction of density functional theory (DFT) has tremendously aided the application of computational material science in the design and development of drug delivery materials. The use of DFT and other computational approaches avoids time-consuming empirical processes. Therefore, this review explored how the DFT computation may be utilized to explain some of the features of polymer-based drug delivery systems. First, we went through the key aspects of DFT and provided some context. Then we looked at the essential characteristics of a polymer-based drug delivery system that DFT simulations could predict. We observed that the Gaussian software had been extensively employed by researchers, particularly with the B3LYP functional and 6-31G(d, p) basic sets for polymer-based drug delivery systems. However, to give researchers a choice of basis set for modelling complicated organic systems, such as polymer-drug complexes, we then offered possible resources and presented the future trend.

Alkali metal decorated C60 fullerenes as promising materials for delivery of the 5-fluorouracil anticancer drug: a DFT approach

The development of effective drug delivery vehicles is essential for the targeted administration and/or controlled release of drugs. Using first-principles calculations, the potential of alkali metal (AM = Li, Na, and K) decorated C60 fullerenes for delivery of 5-fluorouracil (5FU) is explored. The adsorption energies of the 5FU on a single AM atom decorated C60 are -19.33, -16.58, and -14.07 kcal mol-1 for AM = Li, Na, and K, respectively. The results, on the other hand, show that up to 12 Li and 6 Na or K atoms can be anchored on the exterior surface of the C60 fullerene simultaneously, each of which can interact with a 5FU molecule. Because of the moderate adsorption energies and charge-transfer values, the 5FU can be simply separated from the fullerene at ambient temperature. Furthermore, the results show that the 5FU may be easily protonated in the target cancerous tissues, which facilitates the release of the drug from the fullerene. The inclusion of solvent effects tends to decrease the 5FU adsorption energies in all 5FU-fullerene complexes. This is the first report on the high capability of AM decorated fullerenes for delivery of multiple 5FU molecules utilizing a C60 host molecule.

Electrochemical reduction of NO catalyzed by boron-doped C60 fullerene: a first-principles study

The electrochemical reduction of nitrogen monoxide (NO) is one of the most promising approaches for converting this harmful gas into useful chemicals. Using density functional theory calculations, the work examines the potential of a single B atom doped C60 fullerene (C59B) for catalytic reduction of NO molecules. The results demonstrate that the NO may be strongly activated over the B atom of C59B, and that the subsequent reduction process can result in the formation of NH3 and N2O molecules at low and high coverages, respectively. Based on the Gibbs free energy diagram, it is inferred that the C59B has excellent catalytic activity for NO reduction at ambient conditions with no potential-limiting. At normal temperature, the efficient interaction between the *NOH and NO species might lead to the spontaneous formation of the N2O molecule. Thus, the findings of this study provide new insights into NO electrochemical reduction on heteroatom doped fullerenes, as well as a unique strategy for fabricating low-cost NO reduction electrocatalysts with high efficiency.

Two-dimensionalcovalent triazine frameworks as superior nanocarriers for the delivery of thioguanine anti-cancer drugs: a periodic DFT study

This work aims to introduce a superior nanocarrier for thioguanine (TG) anti-cancer drug delivery, drug release, and cancer therapy through computational chemistry.

First-principles studies on two-dimensional B3O3 adsorbent as a potential drug delivery platform for TEPA anticancer drug

The remarkable properties of pristine B₃O₃ nanosheet as a nanocarrier for adsorption and desorption of TEPA anticancer drug for designing potential drug delivery platform were investigated using periodic DFT calculations. We studied the adsorption energy of all stable complexes formed between the drug molecule and B₃O₃ in gas and aqueous phases along with electronic structure analysis of complexes. Different adsorption configurations were studied for drug/B₃O₃ complexes, including the interaction of the C atom of the triangular ring, O atom in the TEPA drug with the B atom in B₃O₃, and indirect drug interaction the middle of the R1 ring cavity of the B₃O₃ nanosheet. The take-up of TEPA prompts a substantial change of 68.13% in the band gap (E_g) of the B₃O₃ nanosheet in the most stable complex. The present study results affirmed the application of B₃O₃ nanosheet as a potential vehicle for TEPA drugs in the treatment of cancerous tissues.

The adsorption of cathinone drug on the platinum decorated silicon carbide nanosheets: DFT studies

Cathinone (CTN), classified as stimulants, is one of the psychoactive drugs. Although the sale of CTN was controlled by international drug laws, it was still sold on the internet, and its overdose caused many deaths worldwide. As chemical sensors, two-dimensional (2D) nanomaterials have drawn attention to be used in various biological molecules. In the current study, the sensing characteristics of the intrinsic SiC monolayer (SiCM) and its Pt-decorated state (Pt@SiCM) were scrutinized toward the CTN drug by utilizing density functional theory (DFT) calculations. It was illustrated that the SiCM sensing response to CTN is insignificant (~ 10.6 at 298 K) due to the weak interaction with the adsorption energy of -0.25 eV. After the decoration of Pt on the SiCM, it was adsorbed above a hexagonal ring, which formed an η⁶-Pt half-sandwich and the adsorption energy was -3.62 eV. It was found that the Pt@SiCM strongly adsorbed CTN and the adsorption energy was -1.60 eV. Therefore, Pt-decoration augmented the SiCM sensing response to CTN from 10.3 to 716.6. The recovery time obtained for the CTN desorption from the Pt@SiCM surface was 12.7 s, which was short. It was concluded that Pt-decoration makes the SiCM a favorable candidate for CTN identification.

The supramolecularly complexes of calix[4]arene derivatives toward favipiravir antiviral drug (used to treatment of COVID-19): a DFT study on the geometry optimization, electronic structure and infrared spectroscopy of adsorption and sensing

While the world is in search of a vaccine that can cure COVID-19 disease, favipiravir is the most commonly used antiviral drug in the treatment of patients during the pandemic process. In this study, we investigated the host-guest interaction between the popular supramolecule calix[4]arene derivatives and the favipiravir drug by using the DFT (Density Functional Theory) method. The B3LYP hybrid method and 6-31G (d,p) basis set were utilized to determine the optimized structures of the host and guest molecules and their complexes. The negative adsorption energy (∆E) and adsorption enthalpy (∆H) calculated for the complexes formed between calix[4]arene compounds and favipiravir drug molecule mentioned that adsorption of favipiravir molecule was an exothermic process on calix[4]arene structures. On the other hand, among the calixarene derivatives in the study, Gibbs free energy change (∆G) value for the adsorption was only negative on calix[4]arene4 molecule. The infrared spectroscopy (IR) calculations were performed by examining the C=O, O-H and NH2 vibrational frequencies to see the adsorption behavior in the favipiravir-calix[4]arene complex. After adsorption of the favipiravir molecule, HOMO-LUMO gap values decreased significantly for the structures and therefore electrical conductivity increased proportionally. In addition, sensor response factors, Fermi energy levels and workfunction changes of calix[4]arene derivatives were calculated and examined. Charge transfer between the four calix[4]arene compounds and the favipiravir molecule has occurred after adsorption. This attributes that calix[4]arene derivatives can be used as a well-suited favipiravir sensor (electronic and workfunction) and adsorbent at room temperature. Based on the calculations made to see the solvent effect on the adsorption of favipiravir it was determined that it did not affect the interaction between the drug molecule and the calix[4]arene compound too much and the adsorption energy turned into a slightly less negative value.

Adsorption of chloroquine and hydroxychloroquine as potential drugs for SARS-CoV-2 infection on BC3 nanosheets: a DFT study

The adsorption of HCQ on BC3 nanosheets is stronger than that of CQ. The hydrogenated BC3 nanosheet is a more prominent nanocarrier for the CQ and HCQ drugs than the bare BC3 monolayer.

The recent advancement of low-dimensional nanostructured materials for drug delivery and drug sensing application: A brief review

In this review article, we have presented a detailed analysis of the recent advancement of quantum mechanical calculations in the applications of the low-dimensional nanomaterials (LDNs) into biomedical fields like biosensors and drug delivery systems development. Biosensors play an essential role for many communities, e.g. law enforcing agencies to sense illicit drugs, medical communities to remove overdosed medications from the human and animal body etc. Besides, drug delivery systems are theoretically being proposed for many years and experimentally found to deliver the drug to the targeted sites by reducing the harmful side effects significantly. In current COVID-19 pandemic, biosensors can play significant roles, e.g. to remove experimental drugs during the human trials if they show any unwanted adverse effect etc. where the drug delivery systems can be potentially applied to reduce the side effects. But before proceeding to these noble and expensive translational research works, advanced theoretical calculations can provide the possible outcomes with considerable accuracy. Hence in this review article, we have analyzed how theoretical calculations can be used to investigate LDNs as potential biosensor devices or drug delivery systems. We have also made a very brief discussion on the properties of biosensors or drug delivery systems which should be investigated for the biomedical applications and how to calculate them theoretically. Finally, we have made a detailed analysis of a large number of recently published research works where theoretical calculations were used to propose different LDNs for bio-sensing and drug delivery applications.

High load drug release systems based on carbon porous nanocapsule carriers. Ibuprofen case study

This work shows the application of carbon nanocapsules as carriers for sodium ibuprofen release. Hard templating was used to prepare spherical carbon nanocapsules (mean diameter and thick shell of 690 and 70 nm, respectively), exhibiting both micro and mesoporosity. For comparison purposes, a microporous commercial activated carbon and a home-made mesoporous CMK-3 were also studied. All carbons showed similar drug uptake, although microporous commercial carbon and nanocapsules showed higher uptake at low equilibrium concentration due to higher adsorption potential in micropores. Higher and faster release of sodium ibuprofen was observed for carbon nanocapsules at pH 1.8 and 7.4 for a starting load ca. 250 mg g-1. Subsequent loading of carbon nanocapsules by successive evaporation cycles led to a remarkable load of ca. 6010 mg g-1 thanks to sodium ibuprofen filling the internal void volume. In spite of the very high load a fast release was observed at pH 7.4, reaching a release of ca. 100% of the initial sodium ibuprofen load. However, a much slower and lower release was observed at pH 1.8. Thus, the system developed has interesting features for oral drug administration thanks to low toxicity of porous carbon, low release in gastric medium and important release in intestinal medium.

Potential application of pristine and Al-doped graphyne-like BN nanosheet for detection of anticancer fluorouracil drug

We studied the potential application of the pristine and Al-doped graphyne-like BN nanosheets (Al-BN-yne) in 5-fluorouracil (5-FU) drug detection using DFT calculations. The 5-FU drug preferentially adsorbed via its oxygen atom on the B atom of pristine BN-yne with adsorption energy of - 11.7 kcal/mol and no effect on its electronic properties. Replacing a B atom by an Al atom significantly increased the sensitivity and reactivity of BN-yne to the 5-FU drug. Upon the 5-FU interaction with the Al-BN-yne, an energy of 20.3 kcal/mol is released, and the E_g of Al-BN-yne significantly decreased from 4.83 to 3.80 eV, increasing the electrical conductance. Thus, the Al-BN-yne sheet can generate an electronic signal after the 5-FU drug adsorption, being a promising electronic sensor for 5-FU detection. We predicted that the recovery time for 5-FU drug desorption from the Al-BN-yne sheet surface is 0.07 s, demonstrating that it benefits from a short recovery time.

Gamma-butyrolactone drug detection by Al-doped BC3 nanotubes: A density functional theory study

Potential application of a pristine and Al-doped BC₃ nanotube (Al-BC₃NT) is explored in detection of gamma-butyrolactone (GBL) drug using DFT calculations. The GBL drug weakly adsorbed of the pristine BC₃NT with adsorption energy (E_ad) of -11.7 kcal/mol. The electronic properties of pristine BC₃NT were not altered sensibly by the GBL adsorption, indicating that this tube is not a sensor. By Al-doping in the structure of BC₃NT, the GBL interaction was strengthened (E_ad = -21.8 kcal/mol). The E_g of Al-BC₃NT dramatically declined from 2.38 to 1.93 eV, by GBL interaction. The electrical conductance of GBL/Al-BC₃NT was 681 times higher than that of the bare Al-BC₃NT. Thus, the Al-BC₃NT yields an electronic signal after the GBL drug adsorption, being a promising electronic sensor. The recovery time for GBL drug desorption from the Al-BC₃NT surface was predicted to be short (0.9 s). The interaction between the GBL and Al-BC₃NT was strengthened in the ethanol solvent, and the E_ad became more negative (-28.9 kcal/mol).