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1.
J Chromatogr A ; 1719: 464774, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38422707

RESUMO

Ginseng is beneficial in the prevention of many diseases and provides benefits for proper growth and development owing to the presence of various useful bioactive substances of diverse chemical heterogeneity (e.g., triterpenoid saponins, polysaccharides, volatile oils, and amino acids). As a result, understanding the therapeutic advantages of ginseng requires an in-depth compositional evaluation employing a simple and rapid analytical technique. In this work, three types of surface-activated carbon fibers (ACFs) were prepared by gas-phase oxidation, strong acid treatment, and Plasma treatment to obtain CO2-ACFs, acidified-ACFs, and plasma-ACFs, respectively. Three prepared ACFs were compared in terms of their physicochemical characterization (i.e., surface roughness and functional groups). A separation system was built using a column with modified ACFs, followed by mass spectrometry detection to investigate and determine substances of different polarities. Among the three columns, CO2-ACFs showed the optimum separation effect. 13 strong polar compounds (12 amino acids and1 oligosaccharide) and 15 lesser polar compounds (ginsenosides) were separated and identified successfully within 4 min in the ginseng sample. The data obtained by CO2-ACFs-TOF-MS/MS and UHPLC-TOF-MS/MS were compared. Our approach was found to be faster (4 min vs. 36 min) and greener, requiring much less solvent (1 mL vs. 10.8 mL), and power (0.06 vs. 0.6 kWh). The developed methodology can provide a faster, eco-friendly, and more reliable tool for the high-throughput screening of complex natural matrices and the simultaneous evaluation of several compounds in diverse samples.


Assuntos
Ginsenosídeos , Panax , Ginsenosídeos/análise , Espectrometria de Massas em Tandem/métodos , Carvão Vegetal , Fibra de Carbono , Dióxido de Carbono/análise , Extratos Vegetais/química , Aminoácidos , Panax/química , Cromatografia Líquida de Alta Pressão/métodos
2.
J Mech Behav Biomed Mater ; 152: 106436, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38325168

RESUMO

Due to the unique lamellar structures, physicochemical and biological properties, electronegative two-dimensional (2D) materials have been explored for surface modification of carbon fibers reinforced polyetheretherketone (CFR-PEEK) composite. Deposition of electronegative 2D materials based on a porous surface created by concentrated H2SO4 has been studied to promote osteogenesis of CFR-PEEK. Generally, a porous layer will be pre-built on CFR-PEEK through severe corrosion of concentrated sulfuric acid to help the loading of 2D materials. However, the severe corrosion will greatly reduce surface mechanical strength, especially wear resistance and hardness, which increases the risk of collapse or even peeling of the bioactive coating by external force. Herein, instead of the severe corrosion, a mild corrosion by concentrated HNO3 was applied to modify the surface of CFR-PEEK to pre-create a dense transition layer for the further surface decoration of electronegative 2D materials (graphene oxide (GO) and black phosphorus (BP), representatively). The results indicated that hardness and wear resistance of the dense transition layer were markedly higher than those of the porous layer. Although GO and BP can be both loaded on these two transition layers, -SO3H on the porous transition layer showed moderate cytotoxicity, while -NO2 on the dense transition layer showed good cytocompatibility. The dense transition layer displayed higher mineralized deposition in vitro and new bone formation rate in vivo than the porous transition layer, moreover, GO and BP coatings improved osteogenesis. This work offers inspirations for the construction of electronegative 2D material coating on CFR-PEEK based on chemical transition layers.


Assuntos
Benzofenonas , Grafite , Osteogênese , Polímeros , Próteses e Implantes , Fibra de Carbono , Cetonas , Fósforo , Polietilenoglicóis
3.
Bioresour Technol ; 393: 130095, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38029804

RESUMO

A pilot-scale carbon fibers enhanced ecological floating beds (CF-EFBs) was constructed. Compared to EFBs without carbon fibers enhancement, CF-EFBs have the better removal of total inorganic nitrogen (TIN), total phosphorus (TP), and chemical oxygen demand (COD), the removal efficiencies were 3.19, 3.49, and 2.74 times higher than EFBs. Throughout the pilot test (under three different coverage rates), the concentrations of COD, TIN and TP of effluent were 18.11 ± 4.52 mgL-1, 1.95 ± 0.92 mgL-1 and 0.13 ± 0.08 mgL-1. Meanwhile, the average removal of TIN, TP and COD from tailwater was 0.96 gm-2d-1, 0.07 gm-2d-1 and 2.37 gm-2d-1 respectively. When the coverage was 30 %, the CF-EFBs had better nitrogen removal effectiveness (TIN purification ability of 1.49 gm-2d-1). The enrichment of denitrifying bacteria, such as Aridibacter, Nitrospira, Povalibacter, and Phaeodactylibacter increased denitrification efficiency. These results verified the feasibility of CF-EFBs in tailwater treatment at pilot-scale, which was of great significance for the practical application of CF-EFBs.


Assuntos
Purificação da Água , Fibra de Carbono , Nitrogênio , Fósforo , Desnitrificação , Carbono , Reatores Biológicos , Eliminação de Resíduos Líquidos
4.
Ecotoxicol Environ Saf ; 266: 115547, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37806130

RESUMO

China is conducting ecological restoration work in urban water bodies. Under anoxic and anaerobic conditions, pollutants transform and produce odorous and black substances, deteriorating the water quality, which is a significant problem in urban water bodies. Vallisneria natans has received widespread attention for its applications in water treatment and restoration. However, the efficiency by which V. natans reduces water pollution and allows sediment remediation requires further improvement. Therefore, in this study, we investigated the effect of V. natans coupled with carbon fiber on the restoration of water bodies and sediment compared with the control group that grew V. natans without carbon fiber. The oxidation-reduction potential (ORP) was selected as the main evaluation index for the water and sediment. Dissolved oxygen in the water and total organic carbon and total nitrogen (TN) in the sediment were also evaluated. V. natans coupled with carbon fiber significantly increased the ORP; that of surface sediment increased by 50 % and that of the water body increased by 60 % compared with the sediment without any bioremediation. Chemical oxygen demand, total phosphorous, and TN in water decreased by 61.2 %, 22.9 %, and 48.3 %, respectively. These results indicate that planting V. natans with carbon fiber can reduce pollutants in water (including humus) and sediments, effectively improving ORP in water and sediment.


Assuntos
Poluentes Ambientais , Hydrocharitaceae , Poluentes Químicos da Água , Fibra de Carbono , Biodegradação Ambiental , Poluição da Água , Fósforo , Nitrogênio/análise , Poluentes Químicos da Água/análise
5.
Food Chem ; 410: 135365, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36608558

RESUMO

Serving as a world-renowned tonic, ginseng contains various types of bioactive metabolites. The comprehensive profiling of these metabolites may help explore the nutritional value of ginseng. Due to high variety in chemical structures, simultaneous monitoring of these metabolites remains a challenge. Herein, a high-throughput and high-selectivity online derivatization mass spectrometry imaging strategy targeting CC was developed. As a widely existed chemical group, CC acts like a bridge connecting different kinds of metabolites. [d0]/[d10]-Bis(pyridine) iodine tetrafluoroboride reagent was chosen for the derivatization of CC, the detection sensitivity of which increased about 3 magnitudes after derivatization. Assisted by laser ablation carbon fiber ionization mass spectrometry, the spatial distribution of bioactive metabolites in mountain-cultivated and garden-cultivated ginseng were visualized. The correlation heatmap results revealed that metabolites in mountain-cultivated ginseng hold higher correlation than those in garden-cultivated ginseng. The proposed method showed potential in providing comprehensive information on the nutrient content of foods.


Assuntos
Carbono , Panax , Fibra de Carbono , Carbono/metabolismo , Jardins , Panax/química , Espectrometria de Massas , Lasers
6.
BMC Musculoskelet Disord ; 24(1): 63, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36694169

RESUMO

BACKGROUND: Proximal humerus fractures are often treated with a fixed-angle titanium plate osteosynthesis. Recently, plates made of alternative materials such as carbon fibre-reinforced polyetheretherketone (CFR-PEEK) have been introduced. This study presents the postoperative results of patients treated with a CFR-PEEK plate. METHODS: Patients with proximal humerus fractures treated with a CFR-PEEK plate (PEEKPower™ Humeral Fracture Plate (HFP)) were included. In follow-up examination, age and gender adjusted Constant-Murley Score (ACS), Subjective Shoulder Value (SSV), Quick Disabilities of the Arm, Shoulder and Hand Score (QDASH) and pain score (Visual Analog Scale (VAS)) were analyzed. General condition at follow-up was measured by European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L). Range of motion was recorded. In addition, radiographs at follow-up, unfavorable events and revision rate were analyzed. RESULTS: In total, 98 patients (66.0 ± 13.2 years, 74 females, 24 males) were reexamined. Mean follow-up was 27.6 ± 13.2 months. There were 15 2-part, 28 3-part and 55 4-part fractures. The functional scores showed good results: SSV 83.3 ± 15.6%, QDASH 13.1 ± 17.0 and ACS 80.4 ± 16.0. A 4-part-fracture, head split component, nonanatomic head shaft reposition and preoperative radiological signs of osteoarthritis were significant negative predictors for poorer clinical scores. Unfavourable events were observed in 27 patients (27.6%). Revision surgery was performed in 8 (8.2%) patients. Risk factors for an unfavourable event were female gender, age of 50 years and older, diabetes, affected dominant hand, 4-part fracture, head split and preoperative radiological signs of osteoarthritis. CONCLUSION: There are several advantages of the CFR-PEEK plate (PEEKPower™ Humeral Fracture Plate (HFP)) such as the polyaxial screw placement and higher stability of locking screws. In summary, the CFR-PEEK plate osteosynthesis is a good alternative with comparable clinical results and some biomechanical advantages. Proximal humerus fractures show good clinical results after treatment with a CFR-PEEK plate. The revision rate and the risk of unfavorable events are not increased compared to conventional titanium plate osteosynthesis. LEVEL OF EVIDENCE: IV.


Assuntos
Fraturas do Úmero , Fraturas do Ombro , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Titânio , Qualidade de Vida , Polímeros , Fibra de Carbono , Polietilenoglicóis , Cetonas , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/métodos , Fraturas do Ombro/diagnóstico por imagem , Fraturas do Ombro/cirurgia , Fraturas do Ombro/etiologia , Placas Ósseas/efeitos adversos , Fraturas do Úmero/etiologia , Resultado do Tratamento , Úmero/cirurgia
7.
20230000; s.n; 2023. 82 p. ilus.
Tese em Português | BBO, LILACS | ID: biblio-1525838

RESUMO

Devido a constante necessidade de desenvolver materiais biocompatíveis com propriedades osteocondutores e osteoindutoras, a presente tese conta com o desenvolvimento de dois estudos in vitro com fibra de carbono obtida a partir de fibra PAN têxtil, incorporada com diferentes íons de metais, na osteogênese com vistas à compreensão das necessidades da engenharia tecidual no desenvolvimento desse biomaterial com adequadas propriedades biológicas. As células foram obtidas dos fêmures de 09 ratos machos adultos (Wistar) pesando 300g, com 90 dias.Estudo 1: A partir da preparação da fibras foram obtidos corpos de prova de 4 mm de diâmetro e 2 mm de altura, dos seguintes grupos: fibra de carbono não ativada (FCNA), fibra carbono ativada (FCA) e fibra carbono ativada com prata (FCAAg). Após plaqueamento (n=5) em meio suplementado (MTS) e meio suplementado osteogênico (MTSO) foram analisados: viabilidade celular, conteúdo de proteína total (PT), atividade de fosfatase alcalina (ALP), interaçãocelular e formação de nódulos de mineralização. Foi avaliada a formação de biofilme nos corpos de prova, utilizando cepas de S. aureus, P. aeruginosa e E. coli. Na viabilidade celular, houve diferença estatística entre grupo controle celular (C) e FCA-MTS, FCAAg-MTS e FCAAg-MTSO. Em PT, não houvediferença, na ALP houve diferença entre C-MTS e as fibras, C-MTSO se mostrou semelhante. Em nódulos, houve diferença entre C-MTS e C-MTSO e as fibras do MTSO. Houve redução de formação de biofilme do S. aureus na FCAAg.Estudo 2: Foram obtidos corpos de prova da mesma dimensão do estudo 1 (n=5) dos seguintes grupos: fibra carbono ativada com prata (FCAAg), fibra carbono ativada com ouro (FCAAu), fibra carbono ativada com cobre (FCACu), fibra carbono ativada com paládio (FCAPd) e fibra carbono ativada com platina (FCAPt). Foram quantificadas a proliferação celular, viabilidade celular, formação de nódulos de mineralização, conteúdo de PT e ALP. Todas as amostras mostraram-se semelhantes quanto a proliferação celular, com exceção do grupo FCAAg comparado ao grupo controle (C). Sobre viabilidade celular, C obteve maior viabilidade que os outros grupos, e FCA obteve maior taxa que os grupos FCAAg, FCACu, FCAPt, sendo semelhante aos grupos FCAAu e FCAPd. Já os grupos FCAAu e FCAPd apresentaram diferença aos grupos FCAAg e FCACu. Na análise de expressão de PT apenas houve diferença entre FCA e FCAAu, sendo FCAAu com menor expressão de produção de PT. Na avaliação da ALP os grupos FCAAg e FACu mostraram diferença estatística e inferior com os grupos C, FCAAu, FCAPd e FCAPt, além disso, o grupo FCA mostrou menor taxa que C.Conclusões: As fibras utilizadas de base para a incorporação dos íons demonstraram grande potencial para uso como scaffold para reparação óssea, isso porque em ambos os estudos, na forma ativada e não ativada, as fibras apresentaram viabilidade celular e quantificação de cálcio satisfatórias. Sendo a versão não ativada mais econômica no que diz respeito ao tempo e custo de preparação. Mais estudos devem ser empregados a fim de assegurar sua segurança clínica em relação à citotoxicidade da incorporação de íons de ouro e paládio.(AU)


Due to the constant need to develop biocompatible materials with osteoconductive and osteoinductive properties, this thesis involves the development of two in vitro studies with carbon fiber obtained from textile PAN fiber, incorporated with different metal ions, in osteogenesis with a view to understanding the needs of tissue engineering in the development of this biomaterial with adequate biological properties. The cells were obtained from the femurs of 9 adult male rats (Wistar) weighing 300g, aged 90 days. Study 1: From the fiber preparation, specimens measuring 4 mm in diameter and 2 mm in height were obtained from the following groups: non-activated carbon fiber (FCNA), activated carbon fiber (FCA) and silver-activated carbon fiber (FCAAg). After plating (n=5) in supplemented medium (MTS) and supplemented osteogenic medium (MTSO), cell viability, total protein content (PT), alkaline phosphatase (ALP) activity, cell interaction and formation of mineralization nodules were analyzed. . Biofilm formation was evaluated in the specimens, using strains of S. aureus, P. aeruginosa and E. coli. In cell viability, there was a statistical difference between the cell control group (C) and FCAMTS, FCAAg-MTS and FCAAg-MTSO. In PT, there was no difference, in ALP there was a difference between C-MTS and fibers, C-MTSO was similar. In nodules, there was a difference between C-MTS and C-MTSO and MTSO fibers. There was a reduction in S. aureus biofilm formation on FCAAg. Study 2: Specimens of the same size as in study 1 (n=5) were obtained from the following groups: carbon fiber activated with silver (FCAAg), carbon fiber activated with gold (FCAAu), carbon fiber activated with copper (FCACu), palladium-activated carbon fiber (FCAPd) and platinum-activated carbon fiber (FCAPt). Cell proliferation, cell viability, formation of mineralization nodules, PT and ALP content were quantified. All samples were similar in terms of cell proliferation, with the exception of the FCAAg group compared to the control group (C). Regarding cell viability, C obtained higher viability than the other groups, and FCA obtained a higher rate than the FCAAg, FCACu, FCAPt groups, being similar to the FCAAu and FCAPd groups. The FCAAu and FCAPd groups showed differences to the FCAAg and FCACu groups. In the analysis of PT expression, there was only a difference between FCA and FCAAu, with FCAAu having lower expression of PT production. In the ALP assessment, the FCAAg and FACu groups showed a lower statistical difference compared to the C, FCAAu, FCAPd and FCAPt groups, in addition, the FCA group showed a lower rate than C. Conclusions: The fibers used as the basis for the incorporation of ions demonstrated great potential for use as a scaffold for bone repair, because in both studies, in activated and non-activated form, the fibers showed satisfactory cell viability and calcium quantification. The non-activated version is moreeconomical in terms of preparation time and cost. More studies must be carried out to ensure its clinical safety in relation to the cytotoxicity of the incorporation of gold and palladium ions. (AU)


Assuntos
Animais , Ratos , Osteogênese , Sobrevivência Celular , Biofilmes , Engenharia Tecidual , Fibra de Carbono
8.
Environ Res ; 215(Pt 1): 114045, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35995227

RESUMO

Photosynthetic microbial fuel cells (pMFC) represent a promising approach for treating methanol (CH3OH) wastewater. However, their use is constrained by a lack of knowledge on the extracellular electron transfer capabilities of photosynthetic methylotrophs, especially when coupled with metal electrodes. This study assessed the CH3OH oxidation capabilities of Rhodobacter sphaeroides 2.4.1 in two-compartment pMFCs. A 3D nickel (Ni) foam modified with plasma-grown graphene (Gr) was used as an anode, nitrate mineral salts media (NMS) supplemented with 0.1% CH3OH as anolyte, carbon brush as cathode, and 50 mM ferricyanide as catholyte. Two simultaneous pMFCs that used bare Ni foam and carbon felt served as controls. The Ni/Gr electrode registered a two-fold lower charge transfer resistance (0.005 kΩ cm2) and correspondingly 16-fold higher power density (141 mW/m2) compared to controls. The underlying reasons for the enhanced performance of R. sphaeroides at the graphene interface were discerned. The real-time polymerase chain reaction (PCR) analysis revealed the upregulation of cytochrome c oxidase, aa3 type, subunit I gene, and Flp pilus assembly protein genes in the sessile cells compared to their planktonic counterparts. The key EET pathways used for sustaining CH3OH oxidation were discussed.


Assuntos
Fontes de Energia Bioelétrica , Grafite , Carbono , Fibra de Carbono , Eletrodos , Complexo IV da Cadeia de Transporte de Elétrons , Ferricianetos , Metanol , Níquel , Nitratos , Sais , Águas Residuárias
9.
Environ Sci Pollut Res Int ; 29(59): 88951-88961, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35841510

RESUMO

N-doped carbon fibers (NCFs) were in situ prepared by Camellia sinensis branches waste through hydrothermal carbonization with urea/ZnCl2 at 160-280 °C under 0.8-8.9 MPa. The structural characteristics of NCFs were investigated by elemental analysis, SEM, TEM, XRD, XPS, Raman spectra, and BET surface area. The highest N content of NCFs obtained at 280 °C was 8.96%, and the main forms of doped N were pyridinic N, pyrrolic N, and graphitic N. Moreover, NCFs were applied to remove metal ions successfully. The results showed that NCF-240 had the maximum adsorption amounts of 106.52, 125.23, and 153.49 mg/g for Cu2+, Pb2+, and Zn2+, respectively, while NCF-280 had the best removal ability on Cr6+ (145.67 mg/g). Finally, it demonstrated that the adsorption behavior of NCFs was well fitted by the pseudo-second-order kinetic and the Langmuir adsorption isotherm models.


Assuntos
Camellia sinensis , Metais Pesados , Poluentes Químicos da Água , Fibra de Carbono , Poluentes Químicos da Água/análise , Adsorção , Íons , Cinética
10.
J Biomech Eng ; 144(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34318320

RESUMO

Ankle foot orthoses (AFOs) control the position and motion of the ankle, compensate for weakness, and correct deformities. AFOs can be classified as passive or powered. Powered AFOs overcome the limitations of passive AFOs by adapting their performance to meet a variety of requirements. However, the actuators currently used to power AFOs are typically heavy, bulky, expensive, or limited to laboratory settings. Thus, there is a strong need for lightweight, inexpensive, and flexible actuators for powering AFOs. In this technical brief, carbon fiber/silicone rubber (CF/SR) twisted and coiled artificial muscles (TCAMs) are proposed as novel actuators for powered AFOs. CF/SR TCAMs can lift to 12,600 times their weight with an input power of only 0.025 W cm-1 and are fabricated from inexpensive materials through a low-cost manufacturing process. Additionally, they can provide a specific work of 758 J kg-1 when an input voltage of 1.64 V cm-1 is applied. Mechanical characterization of CF/SR TCAMs in terms of length/tension, tension/velocity, and active-passive length/tension is presented, and results are compared with the performance of skeletal muscles. A gait analysis demonstrates that CF/SR TCAMs can provide the performance required to supplement lower limb musculature and replicate the gait cycle of a healthy subject. Therefore, the preliminary results provided in this brief are a stepping stone for a dynamic AFO powered by CF/SR TCAMs.


Assuntos
Órtoses do Pé , Tornozelo , Articulação do Tornozelo , Fenômenos Biomecânicos , Fibra de Carbono , Marcha/fisiologia , Músculo Esquelético
11.
Biosens Bioelectron ; 195: 113667, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598107

RESUMO

Measurement of signal molecule is critically important for understanding living systems. Nitric oxide (NO) is a key redox signal molecule that shows diverse roles in virtually all life forms. However, probing into NO's activities is challenging as NO has restricted lifetime (<10 s) and limited diffusion distance (usually <200 µm). So, for the direct acupuncture of NO within the time-space resolution, an electrochemical microsensor has been designed and fabricated in this work. Fabrication of the microsensor is achieved by (1) selective assembly of an electrocatalytic transducer, (2) attaching the transducer on carbon fiber electrode, and (3) covered it with a screen layer to reduce signal interference. The fabricated microsensor exhibits high sensitivity (LOD, 13.5 pM), wide detection range (100 pM-5 µM), and good selectivity. Moreover, studies have revealed that the availability of the sensor for efficient detection of NO is due to the formation of a specific DNA/porphyrin hybrid structure that has synergetic effects on NO electrocatalysis. Therefore, NO release by cells and tissues can be directly and precisely traced, in which we have obtained the release pattern of NO by different cancer cell lines, and have known its dynamics in tumor microenvironment. The fabricated electrocatalytic microsensor may provide a unique and useful tool for the direct assay of NO with high time-space resolution, which promisingly gives a technical solution for the bioassay of NO in living systems.


Assuntos
Terapia por Acupuntura , Técnicas Biossensoriais , Fibra de Carbono , Eletrodos , Óxido Nítrico
12.
Anal Chim Acta ; 1136: 62-71, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33081950

RESUMO

Ultrasonic extraction and nebulization in real-time/carbon fiber ionization mass spectrometry (UEN/CFI-MS) was developed to screen the synthetic drugs adulterated into herbal products such as antidiabetic drug, antihypertensive drug, and hypolipidemic drug. Recently, ambient ionization MS techniques have achieved great advance for rapid analysis of sample surface. However, direct analysis of the analytes inside samples remains a challenge due to a lack of effective online sample extraction procedures. Owing to disappointing desorption efficiency, analytes inside the sample suffer from low detecting sensitivity when applying ambient ionization MS techniques. In this study, online ultrasonic extraction combined with carbon fiber ionization was used for real-time extraction, nebulization and detection of the analytes inside samples. The ultrasonic atomizer could produce a high-frequency vibration to realize online extraction and nebulization of sample. Then, the produced sample droplets could be immediately ionized by the carbon fiber ionization mass spectrometry. UEN/CFI-MS has shown great compatibility to solvents and compounds with a wide range of polarity and has few limitations for the shape of sample. UEN/CFI-MS was successfully applied for the rapid screening of synthetic drugs adulterated into herbal products. Among 37 batches of herbal products, 1 batch of Chinese patent medicine and 6 batches of dietary supplements were detected to be adulterated with the synthetic chemicals without labeling.


Assuntos
Medicamentos Sintéticos , Fibra de Carbono , Suplementos Nutricionais/análise , Espectrometria de Massas , Ultrassom
13.
Artigo em Inglês | MEDLINE | ID: mdl-32731444

RESUMO

In order to investigate the adsorption characteristics of activated carbon fibers (ACFs) with improved surface morphologies towards volatile organic compounds (VOCs), a commercial low-grade ACF was surface modified by successive surface treatment (ST) and chemical activation (CA) process. O3 was used as an ST agent for the formation of oxygen-containing functional groups on the carbon matrix of ACFs. CA was carried out after ST, using a KOH solution. After the successive ST-CA process, Brunauer-Emmett-Teller (BET) surface area and average pore diameter of ACFs were increased from 1483 m2/g to 2743 m2/g and enlarged from 1.931 nm to 2.512 nm, respectively. The successive ST-CA process also resulted in the adsorption capacities of benzene, toluene, and xylene of the ACFs to increase from 0.22 g-Ben./g-ACFs, 0.18 g-Tol./g-ACFs, and 0.19 g-Xyl/g-ACFs up to 0.37 g-Ben./g-ACFs, 0.35 g-Tol./g-ACFs, and 0.38 g-Xyl/g-ACFs, respectively.


Assuntos
Carvão Vegetal , Gases/química , Metais Alcalinos , Ozônio/química , Adsorção , Fibra de Carbono
14.
Chemosphere ; 246: 125783, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31918096

RESUMO

Developing an efficient and metal-free bifunctional catalyst for the simultaneous degradation of antibiotic and reduction of Cr (VI) has been regarded as increasingly attractive yet challenging objectives in the environmental catalysis field. Herein, phosphorus-doped carbon fibers (P-CFs) was innovatively prepared by doping and calcination methods, characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Sulfamethoxazole (SMX) as the target contaminant was selected to evaluate the catalytic activity of P-CFs in PMS activation, over 90% SMX removal and 82.75% mineralization were high-efficiently achieved in the P-CFs/peroxymonosulfate (PMS) system. Particularly, P-CFs/PMS system exhibited a superior catalytic oxidation performance over a wide pH range (3.5-9.5) and even in the complicated water matrix. Surprisingly, the presence of humic acid (HA) in the P-CFs/PMS system could achieve about 2 times enhancement on SMX removal, different from most reports about the inhibition of HA in PMS activation. More importantly, Brunauer-Emmett-Teller (BET) method and XPS analysis revealed that the highly toxic Cr (VI) could be reduced to Cr (III) by P-CFs. Furthermore, electron spin resonance (ESR) combined with various trapping agents demonstrated that SO4•-, •OH and 1O2. were generated and participated in the SMX degradation, while the free electron in P-CFs played a main role in Cr (VI) reduction. This finding not only provided a high-efficiency strategy in the treatment of wastewaters containing organic contaminants and heavy metals Cr (VI), but might open new insights into an innovative metal-free catalyst in environment remediation.


Assuntos
Fibra de Carbono/química , Cromo/química , Fósforo/química , Sulfametoxazol/química , Poluentes Químicos da Água/química , Catálise , Metais , Oxirredução , Peróxidos , Espectroscopia Fotoeletrônica , Água , Purificação da Água/métodos
15.
Zhongguo Zhen Jiu ; 40(1): 109-11, 2020 Jan 12.
Artigo em Chinês | MEDLINE | ID: mdl-31930910

RESUMO

A mini-infrared moxibustion instrument was developed on the base of carbon fiber heating film. This new type moxibustion instrument integrated the moxibusiton technique of TCM with modern technology. It is composed of a power module, an infrared generator module, a temperature sensor, a display screen and a main control panel. The carbon fiber is adopted as the material for infrared generator, which produces infrared rays in the range of the life light wave (from 8 to 15 µm), characterized as precise control of temperature, small gradient and wide range of temperature adjustment. The users can adjust the temperature and time of moxibustion by themselves. The instrument is small in size, light in weight, easy to carry and charge as well as comfortable and safe in application. It can be fixed directly at the required region without the posture restriction and be used whenever needed. Using PowerLab multichannel physiological recorder, the temperature carve is detected at different setting temperatures. The results show that the temperature is increased rapidly and stable.


Assuntos
Moxibustão , Pontos de Acupuntura , Fibra de Carbono , Temperatura
16.
Se Pu ; 38(3): 332-340, 2020 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-34213213

RESUMO

Pyrethroids (PYs) and organochlorine pesticides (OCPs) are widely used to control pests and diseases in plants; however, they threaten human health. In this study, a metal-organic framework/carbon-nitrogen nanosheet composite nanomaterial (UiO-66/HOCN)-coated solid-phase microextraction (SPME) fiber was prepared by in-situ thermal polymerization. The prepared UiO-66/HOCN composite material was characterized by transmission electron microscopy, X-ray diffraction, nitrogen adsorption porosimetry, thermogravimetric analysis, and zeta potentiometry. The prepared UiO-66/HOCN composite-coated MSPE fiber was used for the enrichment and separation of OCPs and PYs, which showed good thermal and chemical stability as well as high extraction efficiency. Combined with gas chromatography-mass spectrometry (GC-MS), an efficient and sensitive method for the detection of trace levels of OCPs and PYs was developed. Under the optimal experimental conditions, wide linear ranges (0.1-800.0 ng/L), good linearity (≥ 0.9978), low limits of detection (0.03-0.30 ng/L), and acceptable repeatability (RSD ≤ 8.9%, n=3) were obtained. Typical black tea samples were analyzed by the developed method, and trace levels of aldrin (6.6 ng/g), α -endosulfan (54.7 ng/g), and bifenthrin (185.8 ng/g) were detected. The results demonstrate that the developed method has immense potential for the detection of pesticides in a complicated matrix.


Assuntos
Análise de Alimentos , Estruturas Metalorgânicas , Resíduos de Praguicidas/análise , Chá/química , Carbono , Fibra de Carbono , Nanoestruturas , Nitrogênio , Polimerização , Microextração em Fase Sólida
17.
J Chromatogr A ; 1612: 460638, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-31676087

RESUMO

Magnetic solid phase extraction (MSPE) employing oil-palm fiber activated carbon (OPAC) modified with magnetite (Fe3O4) and polypyrrole (OPAC-Fe3O4-PPy) was successfully used for the determination of two organochlorine pesticides (OCPs), namely endosulfan and dieldrin in environmental water samples. Analysis was performed using gas chromatography with micro-electron capture detection (GC-µECD). The effects of three preparation variables, namely Fe3O4:OPAC ratio, amount of pyrrole monomer, and amount of FeCl3 oxidant were optimized using Box-Behnken design (BBD) (R2 < 0.99, p-value < 0.001%). The optimum conditions were as follows: Fe3O4:OPAC ratio of 2:1 w/w, 1 g of FeCl3 and 100 µL of pyrrole monomer. The experimental results obtained agreed satisfactorily with the model prediction (> 90% agreement). Optimized OPAC-Fe3O4-PPy composite was characterized using field emission scanning electron microscope, vibrating sample magnetometer and Fourier transform infrared spectroscopy. Four numerical parameters of MSPE procedure was optimized using BBD. The significance of the MSPE parameters were salt addition > sample solution pH > extraction time and desorption time. Under the optimized conditions (extraction time: 90 s, desorption time: 10 min, salt: 0%, and pH: 5.8), the method demonstrated good linearity (25-1000 ng L-1) with coefficients of determination, R2 > 0.991, and low detection limits for both endosulfan (7.3 ng L-1) and dieldrin (8.6 ng L-1). The method showed high analyte recoveries in the range of 98.6-103.5% for environmental water samples. The proposed OPAC-Fe3O4-PPy MSPE method offered good features such as sustainability, simplicity, and rapid extraction.


Assuntos
Cromatografia Gasosa , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Fibra de Carbono , Carvão Vegetal , Elétrons , Óxido Ferroso-Férrico/química , Limite de Detecção , Fenômenos Magnéticos , Óleo de Palmeira , Polímeros , Pirróis/química
18.
Artigo em Chinês | WPRIM | ID: wpr-781759

RESUMO

A mini-infrared moxibustion instrument was developed on the base of carbon fiber heating film. This new type moxibustion instrument integrated the moxibusiton technique of TCM with modern technology. It is composed of a power module, an infrared generator module, a temperature sensor, a display screen and a main control panel. The carbon fiber is adopted as the material for infrared generator, which produces infrared rays in the range of the life light wave (from 8 to 15 μm), characterized as precise control of temperature, small gradient and wide range of temperature adjustment. The users can adjust the temperature and time of moxibustion by themselves. The instrument is small in size, light in weight, easy to carry and charge as well as comfortable and safe in application. It can be fixed directly at the required region without the posture restriction and be used whenever needed. Using PowerLab multichannel physiological recorder, the temperature carve is detected at different setting temperatures. The results show that the temperature is increased rapidly and stable.


Assuntos
Pontos de Acupuntura , Fibra de Carbono , Moxibustão , Temperatura
19.
J Chromatogr A ; 1584: 64-71, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-30503699

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are food contaminants; besides, their oxygenated (oxy-PAHs) and nitrated (nitro-PAHs) derivatives have also been detected in some foods. This is worrying because these derivatives may be more toxic than PAHs. This study presents a new method for the determination of PAHs and their oxygenated and nitrated derivatives in coffee brew. The analytes were extracted by cold fiber solid phase microextraction (CF-SPME) with analysis by gas chromatography/mass spectrometry. The developed method presented good precision with intra-assay and inter-assay, ranged from 4.5 to 16.4%, and from 9.8 to 19.8%, respectively. Recovery ranged from 82.1 to96.3% and linearity showed good adjustment presenting determination coefficients (R2) from 0.980 to 0.999. The limits of quantification ranged from 0.025 to 0.224 µg L-1. The proposed method is simple, versatile, allows simultaneous extraction of PAHs, nitrated and oxygenated derivatives and was successfully applied to the analysis of commercial coffee samples. Benzo(k)fluoranthene, benzo(b)fluoranthene, pyrene, acenaphthylene and acenaphthene are the most abundant PAHs found in samples. In addition, 5,12-naphthacenequinone was the most abundant oxy-PAH and 1-nitropyrene was the most abundant nitro-PAH.


Assuntos
Fibra de Carbono/química , Café/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nitratos/química , Oxigênio/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Microextração em Fase Sólida/métodos , Contaminação de Alimentos/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação
20.
Adv Healthc Mater ; 7(24): e1800990, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30565899

RESUMO

Effective and quick screening and cardiotoxicity assessment are very crucial for drug development. Here, a novel composite hydrogel composed of carbon fibers (CFs) with high conductivity and modulus with polyvinyl alcohol (PVA) is reported. The conductivity of the composite hydrogel PVA/CFs is similar to that of natural heart tissue, and the elastic modulus is close to that of natural heart tissue during systole, due to the incorporation of CFs. PVA/CFs remarkably enhance the maturation of neonatal rat cardiomyocytes (NRCM) in vitro by upregulating the expression of α-actinin, troponin T, and connexin-43, activating the signaling pathway of α5 and ß1 integrin-dependent ILK/p-AKT, and increasing the level of RhoA and hypoxia-inducible factor-1α. As a result, the engineered cell sheet-like constructs NRCM@PVA/CFs display much more synchronous, stable, and robust beating behavior than NRCM@PVA. When exposed to doxorubicin or isoprenaline, NRCM@PVA/CFs can retain effective beating for much longer time or change the contractile rate much faster than NRCM@PVA, respectively, therefore representing a promising heart-like platform for in vitro drug screening and cardiotoxicity assessment.


Assuntos
Hidrogéis/química , Alicerces Teciduais/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Fibra de Carbono/química , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Conexina 43/metabolismo , Avaliação Pré-Clínica de Medicamentos , Módulo de Elasticidade , Condutividade Elétrica , Hidrogéis/farmacologia , Mecanotransdução Celular/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Álcool de Polivinil/química , Ratos , Engenharia Tecidual , Regulação para Cima/efeitos dos fármacos
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