Understanding the Interaction Mechanism between the Epinephrine Neurotransmitter and Small Gold Nanoclusters (Aun; n = 6, 8, and 10): A Computational Insight

In this study, the interaction between the neurotransmitter epinephrine and small gold nanoclusters (AunNCs) with n = 6, 8, and 10 is described by density functional theory calculations. The interaction of Au6, Au8, and Au10 nanoclusters with epinephrine is governed by Au-X (X = N and O) anchoring bonding and Au···H-X conventional hydrogen bonding. The interaction mechanism of epinephrine with gold nanoclusters is investigated in terms of electronic energy and geometrical properties. The adsorption energy values for the most favorable configurations of Au6NC@epinephrine, Au8NC@epinephrine, and Au10NC@epinephrine were calculated to be -17.45, -17.86, and -16.07 kcal/mol, respectively, in the gas phase. The results indicate a significant interaction of epinephrine with AunNCs and point to the application of the biomolecular complex AunNC@epinephrine in the fields of biosensing, drug delivery, bioimaging, and other applications. In addition, some important electronic properties, namely, the energy gap between HOMO and LUMO, the Fermi level, and the work function, were computed. The effect of aqueous media on adsorption energy and electronic parameters for the most favorable configurations was also studied to explore the influence of physical biological conditions.

Nanotechnology-assisted treatment of pharmaceuticals contaminated water

The presence of pharmaceutical compounds in wastewater due to an increase in industrialization and urbanization is a serious health concern. The demand for diverse types of pharmaceutical compounds is expected to grow as there is continuous improvement in the global human health standards. Discharge of domestic pharmaceutical personal care products and hospital waste has aggravated the burden on wastewater management. Further, the pharmaceutical water is toxic not only to the aquatic organism but also to terrestrial animals coming in contact directly or indirectly. The pharmaceutical wastes can be removed by adsorption and/or degradation approach. Nanoparticles (NPs), such as 2D layers materials, metal-organic frameworks (MOFs), and carbonaceous nanomaterials are proven to be more efficient for adsorption and/or degradation of pharmaceutical waste. In addition, inclusion of NPs to form various composites leads to improvement in the waste treatment efficacy to a greater extent. Overall, carbonaceous nanocomposites have advantage in the form of being produced from renewable resources and the nanocomposite material is biodegradable either completely or to a great extent. A comprehensive literature survey on the recent advancement of pharmaceutical wastewater is the focus of the present article.

Group IIIA Single-Metal Atoms Anchored on Hexagonal Boron Nitride for Selective Adsorption Desulfurization via S-M Bonds

Single-atom adsorbents (SAAs) featuring maximized atom utilization and uniform isolated adsorption sites have aroused extensive research interest in recent years as a novel class of adsorption materials research. Nevertheless, it is still challenging to gain a fundamental understanding of the complicated behaviors of SAAs for adsorbing thiophenic compounds (THs). Herein, this work systematically investigated the mechanisms of adsorption desulfurization (ADS) over a single group IIIA metal atom (Ga, In, and Tl) anchored on hexagonal boron nitride nanosheets (BNNSs) via density functional theory (DFT) calculations. First, all the possible doping sites have been considered and their stabilities have been evaluated by the doped energy. DFT calculations reveal that metal atoms prefer to substitute B atoms on BNNSs rather than N atoms. Additionally, SAAs all exhibit considerably enhanced adsorption capacity for THs primarily by the sulfur-metal (S-M) bond with π-π interactions maintained. Among them, In-atom-based SAAs would be adequate to provide the highest adsorption energy (In_cen_B, -40.1 kcal mol^-1). Furthermore, from the perspective of adsorption energy, the SAAs show superior selectivity to THs than aromatic compounds due to the newly formed S-M bond. We hope that our work will manifest the design and application of SAAs in the field of ADS and shed light on a new strategy for fabricating SAAs based on BNNSs.

An Insight into Carbon Nanomaterial-Based Photocatalytic Water Splitting for Green Hydrogen Production

At present, the energy shortage and environmental pollution are the burning global issues. For centuries, fossil fuels have been used to meet worldwide energy demand. However, thousands of tons of greenhouse gases are released into the atmosphere when fossil fuels are burned, contributing to global warming. Therefore, green energy must replace fossil fuels, and hydrogen is a prime choice. Photocatalytic water splitting (PWS) under solar irradiation could address energy and environmental problems. In the past decade, solar photocatalysts have been used to manufacture sustainable fuels. Scientists are working to synthesize a reliable, affordable, and light-efficient photocatalyst. Developing efficient photocatalysts for water redox reactions in suspension is a key to solar energy conversion. Semiconductor nanoparticles can be used as photocatalysts to accelerate redox reactions to generate chemical fuel or electricity. Carbon materials are substantial photocatalysts for total WS under solar irradiation due to their high activity, high stability, low cost, easy production, and structural diversity. Carbon-based materials such as graphene, graphene oxide, graphitic carbon nitride, fullerenes, carbon nanotubes, and carbon quantum dots can be used as semiconductors, photosensitizers, cocatalysts, and support materials. This review comprehensively explains how carbon-based composite materials function as photocatalytic semiconductors for hydrogen production, the water-splitting mechanism, and the chemistry of redox reactions. Also, how heteroatom doping, defects and surface functionalities, etc., can influence the efficiency of carbon photocatalysts in H2 production. The challenges faced in the PWS process and future prospects are briefly discussed.

2D boron nitride incorporating homonuclear boron bonds: stabilized in neutral, anionic and cationic charge

In this work, by means of molecular simulation, we propose two new armchair boron nitride (BN) nanosheets with homonuclear boron bonds with chemical compositions: B30N24H18 and B33N21H18 under the scheme of the density functional theory at the level HSEh1PBE/6–311 +  + g(d,p). The main characteristic that these nanosheets contain is that the homonuclear boron bonds are concentrated at the central zone and the periphery of the central hexagon (B3N3) of the nanosheets, forming pentagonal and triangular geometries. These structural arrangements generate high cohesion energy (for neutral charge − 10.94 and − 10.10 eV/atom, respectively) compared to the nanosheet with heteronuclear bonds (pristine). Also, as a result of quantum simulations, these nanosheets present an insulator (pristine BNNs)—semiconductor (B30N24H18 nanosheet)—conductor-like (B33N21H18 nanosheet) transition. In addition, it is revealed high polarity (in range of 0.30–4.55 D) and possible magnetic behavior for B33N24H18 composition (2.0 magneton bohr). The two nanosheets are stabilized with global neutral charge, anion (− 1|e|) and cation (+ 1|e|), which could be of great interest in the adsorption process and drug delivery.

Quantum mechanical studies of the adsorption of Remdesivir, as an effective drug for treatment of COVID-19, on the surface of pristine, COOH-functionalized and S-, Si- and Al- doped carbon nanotubes

Remdesivir has been recognized as an important medicine in the control of COVID-19 illness. Since carbon nanotubes were considered in the design of novel drug delivery vehicles, the interaction between simple CNT, functionalized CNT by carboxylic group and S-, Al-, and Si-doped CNT and Remdesivir drug were studied using density functional theory (DFT) and time dependent DFT (TDDFT) calculations. The results of this work show that the Si-doped CNT is the best drug delivery system for Remdesivir due to its better electronic, energetic, adsorption and thermodynamic properties.

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.

Drug Delivery Systems on Leprosy Therapy: Moving Towards Eradication?

Leprosy disease remains an important public health issue as it is still endemic in several countries. Mycobacterium leprae, the causative agent of leprosy, presents tropism for cells of the reticuloendothelial and peripheral nervous system. Current multidrug therapy consists of clofazimine, dapsone and rifampicin. Despite significant improvements in leprosy treatment, in most programs, successful completion of the therapy is still sub-optimal. Drug resistance has emerged in some countries. This review discusses the status of leprosy disease worldwide, providing information regarding infectious agents, clinical manifestations, diagnosis, actual treatment and future perspectives and strategies on targets for an efficient targeted delivery therapy.

Effect of Aromatic System Expansion on Crystal Structures of 1,2,5-Thia- and 1,2,5-Selenadiazoles and Their Quaternary Salts: Synthesis, Structure, and Spectroscopic Properties

Rational manipulation of secondary bonding interactions is a crucial factor in the construction of new chalcogenadiazole-based materials. This article reports detailed experimental studies on phenanthro[9,10-c][1,2,5]chalcogenadiazolium and 2,1,3-benzochalcogenadiazolium salts and their precursors. The compounds were synthesized, characterized employing NMR and UV-Vis spectroscopy. TD-DFT calculations were also performed. The influence of the size of the aromatic system on the molecular motifs formed by the compounds in the solid state has been studied by means of single-crystal X-ray diffraction. In case of the salts, the nature of an anion was also taken into consideration. The results show that cyclic [E···N]2 supramolecular synthon connects neighboring molecules of phenanthro[9,10-c][1,2,5]chalcogenadiazoles, with a relatively large aromatic system, in dimers regardless of the chalcogen atom in the molecule. Both N-methyl-2,1,3-benzothiadiazolium and N-methylphenanthro[9,10-c][1,2,5]chalcogenadiazolium cations have a strong affinity for triflate and iodide anions, therefore the formation of S···N or Se···N secondary bonding interactions is observed only in two out of the eight quaternary salts. Less coordinating anions must be used to enable the building blocks studied to form cyclic [E···N]2 synthons. Moreover, for two of the triflate salts, which are isostructural, a new supramolecular motif has been observed.

Quantum mechanical simulation of Chloroquine drug interaction with C60 fullerene for treatment of COVID-19

Chloroquine (CQ) has been reported as an effective drug in the control of COVID-19 infection. Since C60 fullerene has been considered as a drug delivery system, the interaction between pristine fullerene and chloroquine drug and also the interaction between B, Al, Si doped fullerene and chloroquine drug have been investigated based on the density functional theory calculations. The results of this study show that the doped fullerene, especially Al and Si doped fullerene could be the better drug delivery vehicles for chloroquine drug because of their relatively better energetic and electronic properties with chloroquine.

Carbon nanomaterials against pathogens; the antimicrobial activity of carbon nanotubes, graphene/graphene oxide, fullerenes, and their nanocomposites

Recently, antibiotic resistance of pathogens has grown given the excessive and inappropriate usage of common antimicrobial agents. Hence, producing novel antimicrobial compounds is a necessity. Carbon nanomaterials (CNMs) such as carbon nanotubes, graphene/graphene oxide, and fullerenes, as an emerging class of novel materials, can exhibit a considerable antimicrobial activity, especially in the nanocomposite forms suitable for different fields including biomedical and food applications. These nanomaterials have attracted a great deal of interest due to their broad efficiency and novel features. The most important factor affecting the antimicrobial activity of CNMs is their size. Smaller particles with a higher surface to volume ratio can easily attach onto the microbial cells and affect their cell membrane integrity, metabolic procedures, and structural components. As these unique characteristics are found in CNMs, a wide range of possibilities have raised in terms of antimicrobial applications. This study aims to cover the antimicrobial activities of CNMs (both as individual forms and in nanocomposites) and comprehensively explain their mechanisms of action. The results of this review will present a broad perspective, summarizes the most remarkable findings, and provides an outlook regarding the antimicrobial properties of CNMs and their potential applications.

Quasi-planar B36 boron cluster: a new potential basis for ammonia detection

Detection of NH₃ at a trace level is nowadays of great importance. Here, we investigate the reactivity and sensitivity of a B₃₆ borophene toward NH₃ gas employing DFT calculations. The energetic results point out that the adsorption process strongly depends on the orientation of NH₃ relative to the B₃₆ sheet. An NH₃ molecule preferentially interacts via its N-head with a B atom of the B₃₆ with a change of enthalpy of - 90.5 kJ/mol at room temperature and 1 atm. Mulliken charges analysis results reveal that approximately 0.35 |e| transfers from NH₃ to the B₃₆, leaving partially positive NH₃. We found that the B₃₆ electronic properties are meaningfully sensitive to the NH₃ gas, and it may be a sign of further usage of B₃₆ as a potential NH₃ gas sensor. The density of state analysis shows that the B₃₆ gap is expressively decreased from 1.55 to 1.35 eV, increasing its electrical conductance.

Investigation on adsorption features of nitroglycerin on novel red tricycle arsenene nanosheet - A first-principles study

The chemo sensing features of red tricycle arsenene nanosheet (RTANS), a monolayer obtained from allotropes of arsenic is employed in sensing the hazardous vapor nitroglycerin (NG) based on the first-principles investigation. The computations are carried out with the ATK-VNL package. The stability of the RTANS is validated by its formation energy, which is calculated as -4.171 eV/atom. The adsorption energy, Bader charge transfer, energy gap, and its variation after adsorption are the essential parameters that hold up the discussion on RTANS base material as an efficient chemical sensor. Moreover, the target vapor NG is physisorbed on RTANS. Besides, all the essential parameters have been investigated for the interaction of NG on RTANS. The comprehensive study reveals that RTANS can be used as a chemical sensor for the detection of nitroglycerin vapors.

Interaction studies of kidney biomarker volatiles on black phosphorene nanoring: A first-principles investigation

We report the electronic properties of black phosphorene nanoring (BPN) and adsorption behavior of chronic kidney disease biomarker vapors on BPN. The designed BPN is stable, which is ensured by the formation energy with a value of -3.857eV/atom. The band gap of BPN is recorded as 0.716eV showing the semiconductor property. The prominent kidney disease biomarker vapors, namely isoprene, pentanal, hexanal, heptanal are allowed to interact on BPN and studied based on adsorption property on BPN. Based on charge transfer, energy band gap variation and adsorption energy, we studied the adsorption behavior of BPN towards kidney disease biomarkers. Our findings show that BPN can be used to detect the presence of kidney biomarkers.

Ciprofloxacin removal using magnetic fullerene nanocomposite obtained from sustainable PET bottle wastes: Adsorption process optimization, kinetics, isotherm, regeneration and recycling studies

Numerous of pollutants threaten our planet, for instance plastic wastes causes a huge potential risk on the environment in addition to many of emergened pollutants as pharmaceutical residue in aquatic environments which affecting ecological balance and in-turn affecting human health. Accordingly, this research proposed an innovative facile, one-step synthesis of functionalized magnetic fullerene nanocomposite (FMFN) via catalytic thermal decomposition of sustainable poly (ethylene terephthalate) bottle wastes as feedstock and ferrocene as a catalyst and precursor of magnetite. Growth mechanism of FMFN was discussed and batch experiments were achieved to examine its adsorption efficiency in relation to Ciprofloxacin antibiotic. Different adsorption parameters including time, initial Ciprofloxacin concentration, and solution temperature were investigated and optimized using Response Surface Methodology (RSM) model. In addition, a study on the antibiotic adsorption process impact on the organisms of an ecosystem was conducted using E. coli DH5α, and results validated method's efficiency in overcoming problem of appearance of antibiotic-resistant microbes.

Detection of trace level of hazardous phosgene gas on antimonene nanotube based on first-principles method

Using first-principles calculations, electronic characteristics and geometrical stability of pure and Sn substituted armchair β - antimonene nanotube (SbNT) is explored. The adsorption behavior of phosgene (COCl₂) on SbNT is studied using ab initio method. Also, the effect of base material sensitivity with the influence of substitution of Sn dopant is studied. The SbNT energy band structure gets altered upon exposure to the COCl₂ gas molecules. The density-of-states (DOS) spectrum gives the precision on the transfer of charge during the interaction of COCl₂ gas on SbNT material. Moreover, the phosgene molecules interaction on SbNT results in the variation of adsorption energy around -0.578 to -1.364 eV. Further, the average band gap changes are detected in the range of 1.75-19.3% for pristine SbNT, and 192.31-369.23% for Sn substituted SbNT material. The findings suggest that the physisorption of phosgene gas on Sn substituted SbNT is found to be more significant when compared to pristine SbNT. The current work shows that Sn substituted SbNT as a good base material to probe phosgene gas molecules.