Smart implementation of novel advanced nanocarriers such as functionalized C24 and B12N12 nanocages is used supplement for antiviral activity 5-Fluoro-2-hydroxypyrazine-3-carboxamide (Favipiravir; ...Avigan; T-705), as treatment of COVID-19. The interaction energies of Favipiravir with perfect (B12N12 and C24) and doped (BC23 and CB11N12) nanocages were studied at temperatures equal to 310.15 K and 298.15 K using DFT. Our results have shown that the interaction of the Favipiravir (CO group) with BC23 and CB11N12 is more favorable than with the C24 and B12N12 nanocages in the gas and aqueous environments.
Additionally, the natural bond orbital, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), energy gap, chemical reactivity, molecular electrostatic potential, and thermodynamic parameters of the optimized structure have been examined. Furthermore, the UV–Vis and infrared spectroscopy have been evaluated for the investigation of the molecular orbitals Participated in the absorption spectrum of the Favipiravir before and after the interaction with the C24, BC23, B12N12, and CB11N12, sites at maximum wavelength utilizing the time-dependent density functional theory (TD-B3LYP and TD-CAM-B3LYP). The intermolecular interactions have been analyzed by non-covalent interactions (NCI) and also, the electron localization function (ELF) is discussed.
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•Favipiravir drug delivery were investigated by DFT calculation.•The interaction of the drug with the nanocage prefers to bind through the oxygen atom of the drug.•The bandgap of the nanocages was decreased after loading the drug.•Adsorption of drug on nanocage was exothermic.•The chemical reactivity is increased upon drug loading.
Nanopore devices based on graphene and h-BN heterostructures show outstanding electrical and physical characteristics for high throughput label-free DNA sequencing. On top of their suitability for ...DNA sequencing with the ionic current method, G/h-BN nanostructures are promising for DNA sequencing by employing the in-plane electronic current. The influence of the nucleotide/device interaction on the in-plane current has been widely explored for static-optimized geometries. Therefore, it is essential to investigate the dynamics of the nucleotides within the G/h-BN nanopores to gain a comprehensive view of their interaction with the nanopores. In this study, we investigated the dynamic interaction between nucleotides and nanopores in horizontal graphene/h-BN/graphene heterostructures. The insulating h-BN layer, where the nanopores are implemented, changes the in-plane charge transport mechanism into the quantum mechanical tunneling regime. We employed the Car-Parrinello molecular dynamics (CPMD) formalism to investigate the interaction of the nucleotides with nanopores in a vacuum as well as in an aqueous environment. The simulation was performed in the
canonical ensemble with an initial temperature of 300 K. The results indicate that the interaction between the electronegative ends of the nucleotides and the atoms at the nanopore edge is essential for the dynamic behavior of the nucleotides. Moreover, water molecules have a substantial effect on the dynamics and interactions of the nucleotides with nanopores.
The development of bright and long‐lived aqueous room‐temperature phosphorescent (RTP) materials holds paramount importance in broadening the application scope of RTP material system. However, the ...conventional RTP materials usually exhibit low efficiency and short lifetime in aqueous solution. Herein, an in situ host–guest strategy is proposed to achieve cyanuric acid (CA)‐derived phosphorescent carbon nitrogen dots (CNDs) composite (CNDs@CA) that demonstrates a significant enhancement of both quantum yield (QY) and lifetime mediated by water. Detailed investigations reveal that the robust hydrogen bonding networks between CNDs@CA and water effectively stabilize triplet excitons and suppress nonradiative decays, as well as facilitate efficient energy transfer from CA to CNDs, thereby prolonging the lifetime and enhancing the efficiency of RTP. The phosphorescent QY and lifetime of CNDs@CA can be increased to 26.89% (3.9‐fold increase) and 951.25 ms (5.5‐fold increase), respectively, with the incorporation of 50 wt% water under ambient conditions. Even in fully aqueous environments (with up to 400 wt% water added), CNDs@CA exhibits persistent water‐boosted RTP properties, demonstrating exceptional stability. The robust water‐boosted RTP property of CNDs@CA in aqueous solutions presents significant potential for high signal‐to‐noise ratio afterglow bioimaging as well as advanced information encryption.
The present study successfully develops an efficient in situ host–guest approach for synthesizing water‐boosted phosphorescent carbon nitrogen dots through a one‐pot pyrolysis of cyanuric acid. This material exhibits bright and long‐lived aqueous room‐temperature phosphorescence, even in fully aqueous environments, thereby demonstrating significant potential for high signal‐to‐noise ratio afterglow bioimaging both in vitro and in vivo, as well as advanced information encryption applications.
The two independent and NN^
coordination sites of a newly synthesized bis2‐(hydroxyphenyl)‐1,2,4‐triazole platform have been exploited to prepare four monometallic neutral ()PtII complexes carrying ...DMSO, pyridine, triphenylphosphine, or N‐heterocyclic carbene as the fourth ligand. Then, the second NN^
coordination site was used to introduce an IR‐active rhenium tricarbonyl entity, affording the four corresponding heterobimetallic neutral PtII/ReI complexes, as well as a cationic PtII/ReI derivative. X‐ray crystallographic studies showed that distortion of the organic platform occurred to accommodate the coordination geometry of both metal centers. No ligand exchange or transchelation occurred upon incubation of the PtII complexes in aqueous environment or in the presence of FeIII, respectively. The antiproliferative activity of the ligand and complexes was first screened on the triple‐negative breast cancer cell line MDA‐MB‐231. Then, the IC50 values of the most active candidates were determined on a wider panel of human cancer cells (MDA‐MB‐231, MCF‐7, and A2780), as well as on a nontumorigenic cell line (MCF‐10A). Low micromolar activities were reached for the complexes carrying a DMSO ligand, making them the first examples of highly active, but hydrolytically stable, PtII complexes. Finally, the characteristic mid‐IR signature of the {Re(CO)3} fragment in the Pt/Re heterobimetallic complexes was used to quantify their uptake in breast cancer cells.
Pt/Re anticancer agents: The development of heterobimetallic PtII/ReI complexes offers tools for the optimization of the anticancer properties of a new PtII scaffold bearing an pincer ligand associated with a monodentate ligand.
Prodrug photolysis enables spatiotemporal control of drug release at the desired lesions. For photoactivated therapy, near-infrared (NIR) light is preferable due to its deep tissue penetration and ...low phototoxicity. However, most of the photocleavable groups cannot be directly activated by NIR light. Here, we report a upconversion-like process via only one step of energy transfer for NIR light-triggered prodrug photolysis. We utilize a photosensitizer (PS) that can be activated via singlet-triplet (S-T) absorption and achieve photolysis of boron-dipyrromethene (BODIPY)-based prodrugs via triplet-triplet energy transfer. Using the strategy, NIR light can achieve green light-responsive photolysis with a single-photon process. A wide range of drugs and bioactive molecules are designed and demonstrated to be released under low-irradiance NIR light (100 mW/cm
, 5 min) with high yields (up to 87%). Moreover, a micellar nanosystem encapsulating both PS and prodrug is developed to demonstrate the practicality of our strategy in normoxia aqueous environment for cancer therapy. This study may advance the development of photocleavable prodrugs and photoresponsive drug delivery systems for photo-activated therapy.
•Study of oxidation and reduction of 4,7-di(pyrrolidin-1-yl)−1,10-phenanthrolines.•Redox mechanism proposed on the basis of IR and HPLC-MS/MS identification of products.•Reduction leads to cleavage ...of the pyrrolidine moiety from the molecular assembly.•Hydroxylated products are formed by ECEC oxidation process.
The oxidation and reduction mechanisms of substituted 4,7-di(pyrrolidin-1-yl)-1,10-phenanthrolines were investigated in non-aqueous environment by means of cyclic voltammetry. Reduction of these derivatives leads to the formation of radical anion and subsequent reductive cleavage of pyrrolidine-1-yl moiety in overall ECE reduction processes. The regenerating formation of 1,10-phenanthroline was observed. IR spectroelectrochemistry and HPLC-MS/MS analysis were applied to support this result. The presence of pyrrolidine-1-yl moiety significantly thermodynamically facilitates the reduction of the 1,10-phenanthroline structure. Concerning oxidation, the primarily formed cation radical on nitrogen of the pyrrolidine moiety is further oxidized and undergoes a coupled nucleophilic addition of water and hydroxylated compound is formed as the oxidation product. Additionally, further opening of pyrrolidine ring and oxidative cleavage of alkyl are other proposed reactions. The results presented in this work pave the way for novel chelating agents with electrochemically controlled polarity. Furthermore, reductive regeneration of individual components of the molecular assemblies described in this work opens new directions in electrochemical technologies for the environmental protection.
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Photosensitive micromotors that can be remotely controlled by visible light irradiation demonstrate great potential in biomedical and environmental applications. To date, a vast number of ...light‐driven micromotors are mainly composed from costly heavy and precious metal‐containing multicomponent systems, that limit the modularity of chemical and physical properties of these materials. Herein, a highly efficient photocatalytic micromotors based exclusively on a purely organic polymer framework—semiconducting sulfur‐ and nitrogen‐containing donor–acceptor polymer, is presented. Thanks to precisely tuned molecular architecture, this material has the ability to absorb visible light due to a conveniently situated energy gap. In addition, the donor‐acceptor dyads within the polymer backbone ensure efficient photoexcited charge separation. Hence, these polymer‐based micromotors can move in aqueous solutions under visible light illumination via a self‐diffusiophoresis mechanism. Moreover, these micromachines can degrade toxic organic pollutants and respond to an increase in acidity of aqueous environments by instantaneous colour change. The combination of autonomous motility and intrinsic fluorescence enables these organic micromotors to be used as colorimetric and optical sensors for monitoring of the environmental aqueous acidity. The current findings open new pathways toward the design of organic polymer‐based micromotors with tuneable band gap architecture for fabrication of self‐propelled microsensors for environmental control and remediation applications.
Herein, a fully organic polymer‐based micromotor is described. Due to the highly modular donor–acceptor molecular backbone, these microswimmers exhibit pronounced photocatalytic properties, and consequently, fuel‐free motion in pure water just under visible‐light illumination. Multiple functionalities, including photocatalytic degradation of organic pollutants and pH response enable new possibilities for fabrication of microscale devices for environmental monitoring and remediation applications.
Excited-state proton transfer (ESPT) to solvent is often explained according to the two-step Eigen-Weller model including a contact ion pair (CIP*) as an intermediate, but general applicability of ...the model has not been thoroughly examined. Furthermore, examples of the spectral identification of CIP* are scarce. Here, we report on a detailed investigation of ESPT to protic (H
2
O, D
2
O, MeOH and EtOH) and aprotic (DMSO) solvents utilizing a broadband fluorescence technique with sub-200 fs time resolution. The time-resolved spectra are decomposed into contributions from the protonated and deprotonated species and a clear signature of CIP* is identified in DMSO and MeOH. Interestingly, the CIP* intermediate is not observable in aqueous environment although the dynamics in all solvents are multi-exponential. Global analysis based on the Eigen-Weller model is satisfactory in all solvents, but the marked mechanistic differences between aqueous and organic solvents cast doubt on the physical validity of the rate constants obtained.
Time-resolved broadband fluorescence facilitates direct observation of reaction intermediates in excited-state proton transfer to solvent in protic and aprotic solvents.
Natural clay minerals are an inherently colorless class of materials, which have long been known for their versatility as adsorbents due to their interchange capacity, large catalytic support, great ...surface area, and low cost. Herein, we have reported the use of natural clay, collected from the Gabes area, southern Tunisia (Early Cretaceous) for selectively capturing of lead ions from aqueous environments. Our results showed that natural clay samples were mainly composed of silica, alumina, iron and magnesium oxides. Adsorption data showed that the studied clay samples preferably removed substantial amounts of lead ions from water. The removal efficiency of lead ions was about 86.4mg/g of clay and followed pseudo-second-order kinetics. More than 95% of the total adsorptive capacity occurred within 30min. These results suggest the Early Cretaceous clays, Tunisia, turned out to be an effective natural adsorbent for capturing of lead ions from aqueous environment.
•Tunisian natural adsorbents have high adsorptive capacities for heavy metals.•Selective removal of lead ions over other metals by natural adsorbents was achieved.•The removal kinetics was governed by the pseudo-second-order model.•The studied material achieved better removal efficiency than other natural adsorbents.
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