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Noble metallic aerogels with the self-supported hierarchical structure and remarkable activity are promising for methanol fuel cells, but are limited by the severe poisoning and degradation of active sites during electrocatalysis. Herein, the highly stable electrocatalyst of N-doped carbon dots-PtNi (NCDs-PtNi) aerogels is proposed by confining NCDs with alloyed PtNi for methanol oxidation and oxygen reduction reactions. Comprehensive electrocatalytic measurements and theoretical investigations suggest the improvement in structure stability and regulation in electronic structure for better electrocatalytic durability when confining NCDs with PtNi aerogels. Notably, the NCDs-PtNi aerogels perform 12-fold higher activity than that of Pt/C and maintain 52% of their initial activity after 5000 cycles toward acidic methanol oxidation. The enhanced stability and activity of NCDs-PtNi aerogels are also evident for oxygen reduction reactions in different electrolytes. These results highlight the effectiveness of stabilizing metallic aerogels with NCDs, offering a feasible pathway to develop robust electrocatalysts for fuel cells.
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Heterogenizing the molecular catalysts on conductive scaffolds to achieve the isolated molecular dispersion and expected coordination structures is significant yet still challenging. Herein, a sulfur-driving strategy to anchor monodispersed cobalt phthalocyanine on nitrogen and sulfur co-doped graphene (NSG-CoPc) is demonstrated. Experimental and theoretical analysis prove that the incorporation of S dramatically improves the adsorption capability of NSG and evokes the monodispersion of the CoPc molecule, promoting the axial CoâN coordination and the electron delocalization of the Co catalytic center. Benefiting from the reduced activation energy barrier and boosted electron transfer, as well as the maximized active site utilization, NSG-CoPc exhibits outstanding H2O2 oxidization and sensing performance (used as a representative reaction). Moreover, the usage of NSG as a substrate can be readily extended to other metal (Ni, Cu, and Fe) phthalocyanine molecules with molecular-level dispersion. This work clarifies the mechanism of heteroatoms decoration and provides a new paradigm in devising monodispersed molecular catalysts with modulated chemical surroundings for broad applications.
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In recent years, the application of numerical simulation in the research and development(R&D) as well as the pharmaceutical processes of new drugs has expanded considerably. The discrete element method(DEM), an important approach among numerical simulation methods, offers an effective tool for the simulation of discontinuous media. Referring to the research progress of DEM and the formulation of solid traditional Chinese medicine(TCM) preparations in recent years, this paper summarizes and analyzes the application of DEM in the pharmaceutical processes of solid TCM preparations, and discusses the challenges of its application in these processes, in order to provide new methods and ideas for promoting the high-quality production of TCM preparations.
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Medicamentos Herbarios Chinos , Medicina Tradicional China , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Química Farmacéutica/métodos , Composición de Medicamentos/métodosRESUMEN
The quality of traditional Chinese medicine preparations is directly related to the safety of patients. Among the various factors, the process and corresponding critical equipment are critical factors influencing the quality of the preparations. To improve the quality of traditional Chinese medicine preparations, this article summarizes and analyzes the problems in the process links and corresponding critical equipment in the manufacturing process of traditional Chinese medicine preparations. Furthermore, a critical quality attribute evaluation system is established based on safety and effectiveness combined with the drug properties, preparation process, and preparation characteristics, providing a basis for the process and equipment improvements aimed at quality enhancement.
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Medicamentos Herbarios Chinos , Medicina Tradicional China , Humanos , Control de Calidad , ComercioRESUMEN
Sweat wearable sensors enable noninvasive and real-time metabolite monitoring in human health management but lack accuracy and wearable applicability. The rational design of sensing electrode materials will be critical yet challenging. Herein, we report a dual aerogel-based nonenzymatic wearable sensor for the sensitive and selective detection of uric acid (UA) in human sweat. The three-dimensional porous dual-structural aerogels composed of Au nanowires and N-doped graphene nanosheets (noted as N-rGO/Au DAs) provide a large active surface, abundant access to the target, rapid electron transfer pathways, and a high intrinsic activity. Thus, a direct UA electro-oxidation is demonstrated at the N-rGO/Au DAs with a much higher activity than those at the individual gels (i.e., Au and N-rGO). Moreover, the resulting sensing chip displays high performance with a good anti-interfering ability, long-term stability, and excellent flexibility toward the UA detection. With the assistance of a wireless circuit, a wearable sensor is successfully applied in the real-time UA monitoring on human skin. The obtained result is comparable to that evaluated by high-performance liquid chromatography. This dual aerogel-based nonenzymatic biosensing platform not only holds considerable promise for the reliable sweat metabolite monitoring but also opens an avenue for metal-based aerogels as flexible electrodes in wearable sensing.
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Técnicas Biosensibles , Grafito , Dispositivos Electrónicos Vestibles , Humanos , Técnicas Biosensibles/métodos , Grafito/química , Sudor/química , Ácido Úrico/análisis , Técnicas ElectroquímicasRESUMEN
A total of 15 batches of the substance reference of Guizhi Jia Gegen Decoction(GZGGD) were prepared and the characteristic fingerprints of them were established. Furthermore, the similarity of the fingerprints and peak attributes were explored. The extraction rate, and the content and the transfer rate ranges of the index components, puerarin, paeoniflorin, liquiritin, and ammonium glycyrrhizate were determined for the analysis of the quality value transfer. The result demonstrated that the fingerprints of the 15 batches of the samples showed high similarity(>0.99). A total of 15 characteristic peaks were identified from the fingerprints, with 10 for Puerariae Lobatae Radix, 1 for Cinnamomi Ramulus, 2 for Paeoniae Radix Alba, and 2 for Glycyrrhizae Radix et Rhizoma. The content of puerarin was 11.05-18.35 mg·g~(-1) and the average transfer rate was 21.27%-39.49%. The corresponding figures were 7.95-10.90 mg·g~(-1) and 23.28%-43.23% for paeoniflorin, 3.25-4.95 mg·g~(-1) and 32.31%-61.27% for ammonium glycyrrhizate, and 3.65-5.80 mg·g~(-1) and 14.57%-27.05% for liquiritin. The extraction rate of the 15 batches of samples was in the range of 16.85%-21.78%. In this paper, the quality value transfer of the substance reference of GZGGD was analyzed based on characteristic fingerprint, content of index components, and the extraction rate. This study is expected to lay a basis for the quality control and further development of GZGGD.
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Compuestos de Amonio , Medicamentos Herbarios Chinos , Paeonia , Benchmarking , Cromatografía Líquida de Alta PresiónRESUMEN
Pueraria lobatae (Willd) Ohwi is a traditional Chinese medicine used to treat alcohol intoxication, diabetes, cerebrovascular and cardiovascular diseases. Some of its active components include the flavonoids puerarin, daidzin, daidzein, and genistin. The therapeutic efficacy of these agents is hampered by their poor pharmacokinetic profiles (rapid systemic clearance, low oral bioavailability, short half-life) and physicochemical properties (such as poor aqueous solubility and stability). In the current study, chitosan/xanthan gum-based (hydroxypropyl methylcellulose-co-2-acrylamido-2-methylpropane sulfonic acid) hydrogels for the controlled release of Pueraria lobata-solid dispersion (SD) were successfully prepared and characterized. A total of 61 compounds were identified in the Pueraria lobatae-SD using UHPLC-Q-TOF-MS analysis. Hydrogel structure was confirmed by FTIR, XRD, TGA, DSC, and SEM showed a porous structure. Correlations between hydrogels structural properties was also investigated. The hydrogels showed higher swelling after 48 h at pH 1.2 (21.15 %) than pH 7.4 (15.91 %). In vitro drug release study demonstrated that drug release was maximum at pH 1.2 (63 %) compared to pH 7.4 (49 %) after 48 h. The gel fraction of the synthesized hydrogel was increased with the increase in the polymer and crosslinker concentrations. Furthermore, in vitro studies demonstrated that the developed hydrogels possess good antioxidant and antimicrobial properties.
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Quitosano , Pueraria , Ácidos Sulfónicos , Quitosano/química , Pueraria/química , Preparaciones de Acción Retardada , Derivados de la Hipromelosa , Hidrogeles/químicaRESUMEN
Improving the utilization of noble metals is extremely urgent for fuel cell electrocatalysis, while three-dimensional hierarchical noble metal aerogels with abundant sites and channels are proposed to reinforce their electrocatalytic performances and decrease their amounts. Herein, novel Pd aerogels with tunable surface chemical states were prepared through a facile in situ electrochemical activation, starting with PdO x aerogels by the hydrolysis method. The hierarchical porous Pd aerogels showed unprecedented high activity towards the electrocatalytic oxidation of fuels including methanol (2.99 A mgPd -1), ethanol (8.81 A mgPd -1), and others in alkali, outperforming commercial catalysts (7.12- and 13.66-fold, corresponding to methanol and ethanol). Theoretical investigation unveiled the hybrid surface states with metallic and oxidized Pd species in Pd aerogels to regulate the adsorption of intermediates and facilitate the synergistic oxidation of adsorbed *CO, resulting in enhanced activity with the MOR as the model. Therefore, efficient Pd aerogels through the in situ electrochemical activation of PdO x aerogels were proposed and showed great potential for fuel cell anodic electrocatalysis.
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ETHNOPHARMACOLOGICAL RELEVANCE: Gui-Zhi-Jia-Ge-Gen decoction (GJGD) is a classical Chinese medicine prescription that has been widely used in clinical practice for centuries. In recent times, TCM has received considerable attention for its potential efficacy in treating a wind-cold type of common cold. However, the effect of the Gui-Zhi-Jia-Ge-Gen decoction on the wind-cold type of common cold is still not fully understood, which presents challenges for both quality control, research and development. Furthermore, the identification of potential pharmacodynamic ingredients (PPIs) is important for developing quality control procedures for industrial and large-scale production. AIM OF THE STUDY: The aim of this study was to investigate the potential curative effect of Gui-Zhi-Jia-Ge-Gen decoction on wind-type of common cold using multidimensional qualitative analysis that combined water-decoction spectrums, in vivo plasma spectrums, and molecular docking to identify key constituents of GJGD. MATERIALS AND METHODS: Water-based GJGDs were formulated according to the clinical usage documented in ancient medical texts. Ultra-high-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UHPLC-Q-TOF-MS) was combined with computer-aided modeling screening to identify GJGD PPIs in rats following oral administration. Molecular docking experiments were carried out to predict the binding affinity of the PPIs to tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and interleukin-1ß (IL-1ß). Finally, the active ingredients of GJGD were further validated through pharmacodynamic experiments by assessing their efficacy in treating a wind-cold type of common cold in rats. RESULTS: A total of 61 compounds were identified in the GJGD, 8 of which were detected in rat blood samples, providing stronger evidence for PPIs. Molecular docking also confirmed that these 8 compounds had a better affinity for TNF-α, IL-6, and IL-1ß. In animal studies, various doses of the GJGD groups and the positive control groups caused significant elevations (P < 0.05) in the levels of white blood cell count and lymphocyte ratio and caused a significant decrease (P < 0.05) in the monocyte ratio and neutrophilic granulocyte ratio compared to the model group. Organ indexes of the GJGD treated groups were higher than the model group (P < 0.05). Significant neutrophil infiltration, hemorrhage, compensatory vacuole, and interstitium proliferation were observed in the lung tissue of the model group. However, the lung tissues of the various dose groups that received GJGD showed a near normal appearance, except for slight thickening, interstitium proliferation, and compensatory vacuole in some areas. The GJGD was found to be effective against a cold-wind type of common cold, which is in accordance with molecular docking studies suggesting that GJGD may be effective against a cold-wind type of common cold. Finally, based on multidimensional analysis, 8 potential compounds in GJGD were identified as PPIs (puerarin, 3'-hydroxy puerarin, 3'- methoxy puerarin, daidzin, cinnamic acid, paeoniflorin, liquiritin, and glycyrrhizic acid). CONCLUSION: The present study combined water decoction spectral analysis, molecular docking, and in vivo blood plasma spectrum analysis to develop a multidimensional qualitative approach for the development of GJGD and to assess its effectiveness in a wind type of common cold in Sprague Dawley rats. Meanwhile, 8 compounds in the GJGD were identified as PPIs in this study, which may be useful in developing quality standards for complex TCM prescriptions.
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Cinnamomum aromaticum , Resfriado Común , Medicamentos Herbarios Chinos , Animales , Cromatografía Líquida de Alta Presión/métodos , Resfriado Común/tratamiento farmacológico , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Interleucina-6 , Simulación del Acoplamiento Molecular , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/análisis , Agua , VientoRESUMEN
For decades, grain boundary engineering has proven to be one of the most effective approaches for tailoring the mechanical properties of metallic materials, although there are limits to the fineness and types of microstructures achievable, due to the rapid increase in grain size once being exposed to thermal loads (low thermal stability of crystallographic boundaries). Here, we deploy a unique chemical boundary engineering (CBE) approach, augmenting the variety in available alloy design strategies, which enables us to create a material with an ultrafine hierarchically heterogeneous microstructure even after heating to high temperatures. When applied to plain steels with carbon content of only up to 0.2 weight %, this approach yields ultimate strength levels beyond 2.0 GPa in combination with good ductility (>20%). Although demonstrated here for plain carbon steels, the CBE design approach is, in principle, applicable also to other alloys.
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The dataset presented in this paper is supporting the research article "Enhanced magnetic refrigeration capacity in Ni-Mn-Ga micro-particles" (Qian, et al., 2018) [1]. The martensite transformation temperature (Ms ) and the Curie point (Tc ) of the annealed alloys with nominal composition Ni55-xMn20+xGa25 (x = 0, 0.25, 0.5, 1, atomic percent, labeled as A1, A2, A3 and A4, respectively) varied with x, yielding a temperature difference Tc -Mc of 7.2â¯K at x = 0.5 (A3). The magnetization difference (ΔM) between the austenite and martensite, the field dependence of transformation temperature (ΔT/ΔH) and the thermal hysteresis loss of A3 and the according stress relief annealing (SRA) particles were demonstrated. The isothermal magnetization curves of A3 and the SRA particles were measured in order to determine the magnetocaloric effect.