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1.
Mar Life Sci Technol ; 6(3): 535-546, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39219686

RESUMO

Eczema is a common chronic dermatological disease. Conventional treatments exhibit limited efficacy due to fast drug release resulting in short-term relief. Development of a new treatment strategy that enables sustained drug release and long-term maintenance on the skin surface is necessary. A self-adhesive swelling microneedle patch (SDSMNs) was designed and constructed using a two-step casting method. The adhesive substrate was prepared by blending gelatin and dopamine via oxidation of NaIO4, so it could adhere onto the skin surface as well as withstand repeated bending movement without detachment. The swelling needles were fabricated using polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), which could swell by absorbing interstitial fluid and release the drug in a controlled manner. SDSMNs also showed desirable antibacterial activities toward E. coli and S. aureus. The adhesive microneedles loaded with matrine (MAT-SDSMNs), an anti-inflammatory Chinese medicine, dramatically relieved eczema symptoms through IL-17 mediated inflammation responses. The use of MAT-SDSMNs significantly decreased the infiltration of inflammation cells and level of inflammatory cytokines, reduced the skin thickness, and increased collagen deposition fraction compared with conventional ointment or subcutaneous injection. The results suggested that MAT-SDSMNs can improve eczema treatment by regulating the local inflammatory microenvironment, providing a simple, self-administered sustainable strategy for eczema treatment. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-024-00235-z.

2.
J Chem Phys ; 160(24)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38912629

RESUMO

Gap opening remains elusive in copper chalcogenides (Cu2X, X = S, Se, and Te), not least because Hubbard + U, hybrid functional, and GW methods have also failed. In this work, we elucidate that their failure originates from a severe underestimation of the 4s-3d orbital splitting of the Cu atom, which leads to a band-order inversion in the presence of an anionic crystal field. As a result, the Fermi energy is pinned due to symmetry, yielding an invariant zero gap. Utilizing the hybrid pseudopotentials to correct the underestimation on the atomic side opens up gaps of experimental magnitude in Cu2X, suggesting their predominantly electronic nature. Our work not only clarifies the debate about the Cu2X gap but also provides a way to identify which of the different methods really captures the physical essence and which is the result of error cancellation.

3.
J Chem Phys ; 159(1)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37417754

RESUMO

We report a first-principles study on the electronic and optical properties of delafossite CuMO2 (M = Al, Ga and In) using the recently developed hybrid functional pseudopotentials. We obtain trends of the fundamental and optical gaps with increasing M-atomic number, in agreement with experiment. In particular, we reproduce the experimental fundamental gap, optical gap, and Cu 3d energy of CuAlO2 almost perfectly, in contrast to the various calculations that have traditionally focused on valence electrons, which are unable to reproduce these key properties simultaneously. Since all that distinguishes our calculations is simply the use of a different Cu pseudopotential with a partially exact exchange interaction, this suggests that an inappropriate description of the electron-ion interaction may play a role in the density functional theory bandgap problem for CuAlO2. Applying Cu hybrid pseudopotentials to CuGaO2 and CuInO2 is also effective, yielding optical gaps that are very close to experiment. However, due to the limited experimental data for these two oxides, a comprehensive comparison as that for CuAlO2 is not possible. Furthermore, our calculations yield large exciton binding energies for delafossite CuMO2, all around 1 eV.


Assuntos
Elétrons , Óxidos , Óxidos/química , Condutividade Elétrica
4.
Biomater Sci ; 11(11): 3965-3975, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37114937

RESUMO

Precise targeted delivery of therapeutic agents is crucial for tumor therapy. As an emerging fashion, cell-based delivery provides better biocompatibility and lower immunogenicity and enables a more precise accumulation of drugs in tumor cells. In this study, a novel engineering platelet was constructed through cell membrane fusion with a synthesized glycolipid molecule, DSPE-PEG-Glucose (DPG). The obtained glucose-decorated platelets (DPG-PLs) maintained their resting state with structural and functional integrities, while they would be activated and triggered to release their payloads once they arrive at the tumor microenvironment. Glucose decoration was verified to impart the DPG-PLs with stronger binding effects toward tumor cells that overexpress GLUT1 on their surfaces. Together with the natural homing property toward tumor sites and bleeding injury, doxorubicin (DOX)-loaded platelets (DPG-PL@DOX) exhibited the strongest antitumor effects on a mouse melanoma model, and the antitumor effect was significantly enhanced in the tumor bleeding model. DPG-PL@DOX provides an active and precise solution for tumor-targeted drug delivery, especially for postoperative treatments.


Assuntos
Plaquetas , Melanoma , Animais , Camundongos , Sistemas de Liberação de Medicamentos , Doxorrubicina/química , Polietilenoglicóis/química , Linhagem Celular Tumoral , Microambiente Tumoral
5.
Phys Chem Chem Phys ; 22(39): 22236-22243, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33000818

RESUMO

The lack of high-performance anode materials has become a major obstacle to the development of Li- and Na-ion batteries. Recently, 2D transition metal borides (e.g. MBenes) have attracted much attention due to their excellent stability and electrical conductivity. Unfortunately, most of the reported MBene phases typically have an intrinsic metal-rich structure with metal atoms exposed on the surface, which harmfully affect the adsorption of Li/Na atoms. Here, through crystal structure prediction combined with the first-principles density functional theory, a novel TiB3 MBene has been determined by altering the proportion of non-metallic element boron to wrap metal atoms and weaken nearest-neighbor electrostatic repulsion. Electrostatic potential analysis visually shows a surface with low potential on the TiB3 monolayer implying high adsorption capacity, and also can be used to quickly screen out the Li/Na adsorption sites. Accurate half-cell battery simulation confirmably shows that the TiB3 monolayer possesses a theoretical specific capacity of 1335.04 and 667.52 mA h g-1 for Li and Na, respectively. The TiB3 monolayer can remain metallic after adsorbing Li/Na atoms, which ensures good conductivity during battery cycling. The ultra-low barrier energy (only 38 meV for Li) and suitable open-circuit voltage indicate excellent charging and discharging capabilities. These results suggest that the TiB3 monolayer could be a promising anode material for Li- and Na-ion batteries, and provide a simple design principle for exposing non-metallic atoms on the surface.

6.
Molecules ; 25(18)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911715

RESUMO

Dalbavancin is a novel semisynthetic glycopeptide antibiotic that comprises multiple homologs and isomers of similar polarities. However, pharmacokinetic studies have only analyzed the primary components of dalbavancin, namely B0 and B1. In this study, an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed to simultaneously determinate and investigate the five homologous components of dalbavancin, namely, A0, A1, B0, B1, and B2, in rat plasma. In this method, methanol was used to precipitate plasma, and a triple-bonded alkyl chromatographic column was used for molecule separation, using 0.1% formic acid-acetonitrile as the mobile phase for gradient elution. Targeted homologs were analyzed by a triple quadrupole mass spectrometer using positive electrospray ionization in multiple reaction monitoring mode. The linearity range was 50-2500 ng/mL with a high correlation coefficient (r2 > 0.998). This method was successfully applied in the pharmacokinetic analysis of dalbavancin hydrochloride to investigate dalbavancin components in rats.


Assuntos
Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem , Teicoplanina/análogos & derivados , Animais , Monitoramento de Medicamentos , Estrutura Molecular , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Teicoplanina/química , Teicoplanina/farmacocinética
7.
Phys Chem Chem Phys ; 21(34): 18559-18568, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31411206

RESUMO

The development of lithium-sulfur (Li-S) batteries is hindered by capacity loss due to lithium polysulfide (LIPS) dissolution into electrolyte solutions (known as the "shuttle effect"). MXenes with excellent electrical conductivity, high mechanical strength and multiple possible active two-dimensional surface terminations are attracting much attention as anchoring materials of Li-S batteries. Here, the S-functionalized V2C (V2CS2) is designed and demonstrated to have not only dynamic and thermal stability, but also metallic character. Compared with bare V2C and V2CO2, V2CS2 exhibits a moderate adsorption effect to suppress the "shuttle effect" and can preserve the structure of LIPSs without any decomposition. Moreover, the metallic properties of V2CS2 are maintained after LIPSs are adsorbed, which can promote the electrochemical activity during the charge and discharge process. The low energy barriers of Li2S decomposition and Li diffusion on the V2CS2 surface promise the phase transformation of LIPSs and assist the electrochemical process. Based on these remarkable results, we can conclude that V2CS2 is a promising anchoring material for lithium-sulfur batteries. Our work may also inspire the exploration of other MXenes and new surface functionalization methods to improve the performance of MXenes as host materials for high performance Li-S batteries.

8.
J Photochem Photobiol B ; 167: 158-167, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28068610

RESUMO

Clonazepam, a type of benzodiazepine, is a classical drug used to prevent and treat seizures, panic disorder, movement disorder, among others. For further clarifying the distribution of clonazepam in vivo and the pharmacodynamic and pharmacokinetic mechanisms, the binding interaction between clonazepam and bovine serum albumin (BSA) was investigated using ultraviolet spectroscopy (UV), steady-state fluorescence spectroscopy, synchronous fluorescence spectroscopy, three-dimensional (3D) fluorescence spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and molecular docking methods. The results well confirmed that clonazepam bound on the subdomain III A (Site II) of BSA through van der Waals force and hydrogen bonding interaction, and quenched the intrinsic fluorescence of BSA through a static quenching process. The number of binding sites (n) and binding constant (Kb) of clonazepam-BSA complex were about 1 and 7.94×104M-1 at 308K, respectively. The binding process of clonazepam with BSA was spontaneous and enthalpy-driven process due to ΔG0<0 and|ΔH0|>T|ΔS0| over the studied temperature range. Meanwhile, the binding interaction of clonazepam with BSA resulted in the slight change in the conformation of BSA and the obvious change in the conformation of clonazepam, implying that the flexibility of clonazepam also played an important role in increasing the stability of the clonazepam-BSA complex.


Assuntos
Clonazepam/química , Soroalbumina Bovina/química , Ligação de Hidrogênio , Conformação Molecular , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
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