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1.
Anal Bioanal Chem ; 416(13): 3271-3280, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38584179

RESUMO

Accurate quantification of nano-selenium (nSe) and other ionic Se species in aquatic environments is a prerequisite for reliable estimation of their potential hazards. In this study, a micropore membrane filtration-based method followed by ICP-MS analysis was proposed for the selective concentration and determination of nSe in the water column. Polyvinylidene fluoride (PVDF) and nylon micropore filtration membranes were proven to efficiently capture nSe under optimal conditions (retention > 91.0 ± 0.87%). At the same time, ionic selenite and selenate could escape from the membranes, realizing the isolation of nSe and ionic Se species. The interference of dissolved organic matter (DOM) during separation can be resolved by adding Ca(II) ions, which can induce the formation of DOM aggregates by cation bridging effects. nSe retained on PVDF membranes could be effectively eluted with FL-70 (a powerful alkaline surfactant) aqueous solutions (0.5%, m/v) while maintaining the original size and morphology. Although nSe trapped on nylon membranes could not be easily eluted, quantification can also be achieved after membrane digestion. Speciation of ionic selenite and selenate in the filtrate was further conducted with an anion exchange column by using HPLC coupled with ICP-MS. The developed method was used to analyze Se species in six real water samples. Spiking experiments showed that the recoveries of nSe ranged from 70.2 ± 2.7% to 85.8 ± 1.3% at a spike level of 0.2 µg/L, and the recoveries of Se(IV) and Se(VI) ranged from 83.6 ± 0.5% to 101 ± 1% at a spike level of 0.55 µg/L, verifying the feasibility for the analysis of environmental water samples. This work provides possibilities to investigate the transformation and potential risks of nSe in the environment.

2.
Phys Chem Chem Phys ; 26(3): 2449-2456, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38168706

RESUMO

The search for highly active and low-cost single-atom catalysts for the oxygen reduction reaction (ORR) is essential for the widespread application of proton exchange membrane fuel cells. Transition metals anchored on nitrogen-doped graphdiyne (GDY) have attracted considerable interest as potentially excellent catalysts for the ORR. However, the relationship between the active site and nitrogen-doped GDY remains unclear. In this work, we conducted a systematic investigation of sp-hybridized N atoms anchoring single transition metal atoms of 3d and 4d on GDY (TMC2N2) as electrocatalysts for the ORR. Firstly, 18 kinds of TMC2N2 were determined to have good thermodynamic stability. Due to the extremely strong adsorption of *OH, TMC2N2 exhibits inferior ORR performance compared to traditional Pt(111). Considering that *OH adsorption hinders the catalytic activity of TMC2N2, we modified the OH ligand of TMC2N2 to develop the high-valent metal complex (TMC2N2-OH) aiming to enhance the electrocatalytic activity. The adsorption of intermediates on most TMC2N2-OH is weakened after the modification of the OH ligand, especially for the adsorption of *OH. Thus, by comparing the ORR overpotential of catalysts before and after ligand modification, we find that the catalytic activity of different TMC2N2-OHs improves to various degrees. MnC2N2-OH, TMC2N2-OH, and TcC2N2-OH exhibit relatively high ORR catalytic activity, with overpotentials of 0.93 V, 1.19 V, and 0.92 V, respectively. Furthermore, we investigated the cause of improved catalytic activity of TMC2N2-OH and found that the modified coordination environment of the catalyst led to adjusted adsorption of ORR intermediates. In summary, our work sheds light on the relationship between nitrogen-doped GDY and transition metal sites, thus contributing to the development of more efficient catalysts.

3.
Biomed Chromatogr ; 38(5): e5830, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38445357

RESUMO

Hong-Hua-Xiao-Yao tablet (HHXYT) is attracting attention increasingly because of its use in treatment of mammary gland hyperplasia (MGH) and menopausal syndrome. However, its pharmacokinetics remains unclear. This study developed a sensitive and rapid method for simultaneous determination of 10 compounds of HHXYT in rat plasma by liquid chromatography-tandem mass spectrometry and to compare the pharmacokinetics of these compounds in MGH rats and sham operated rats. The linearity, accuracy, precision, stability and matrix effect were within acceptable ranges. This established method was successfully applied to a pharmacokinetics study of 10 compounds in sham operated and MGH rats. According to the results, the bioavailability of glycyrrhetinic acid was highest in MGH rats and sham operated rats. The mean residence times of glycyrrhetinic acid and glycyrrhetinic acid 3-O-glucuronide were higher than those of the other compounds while the mean residence time and half-life of liquiritin, isoliquiritin and paeoniflorin were lower. Some pharmacokinetic parameters of ormononetin, liquiritigenin, isoliquiritigenin, liquiritin, isoliquiritin, paeoniflorin, protocatechuic acid and senkyunolide I were significantly different between MGH rats and sham operated rats. This study elucidated the dynamic changes of multiple components in rats after oral administration of HHXYT systematically and comprehensively, which provided guidance for clinical application.


Assuntos
Medicamentos de Ervas Chinesas , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Animais , Ratos , Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Feminino , Modelos Lineares , Cromatografia Líquida/métodos , Comprimidos/farmacocinética , Chalconas/farmacocinética , Chalconas/química , Chalconas/sangue , Disponibilidade Biológica , Limite de Detecção , Ácido Glicirretínico/farmacocinética , Ácido Glicirretínico/sangue , Ácido Glicirretínico/química
4.
Phys Chem Chem Phys ; 25(42): 29173-29181, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37870382

RESUMO

Seeking cost-effective and earth-abundant electrocatalysts with excellent activity for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) in zinc-air batteries (ZABs) is critically important. In this work, the ORR and OER performance of the Fex cluster supported on FeN4 composite sites (FeN4@Fex) is investigated based on density functional theory. Based on the charge density difference between the Fex cluster and the FeN4 substrate, the conclusion that the decreased charge density of the chemical bond between the metal and the adsorbate can weaken the adsorption of the adsorbate can be drawn. The results of the d-band center also confirm this. Furthermore, the ORR and OER free energy change profiles show that FeN4@Fe8 exhibits the best ORR and OER activity. This is because the electronic environment regulated by the Fex cluster can improve the adsorption of intermediates, which is conducive to enhancing catalytic activity. Further considering the solution environment, the activity of FeN4@Fex with preadsorbed OH (FeN4@Fex(OH)y) was studied. It is found that FeN4@Fe8(OH)6 is still the best catalyst. This work introduces new highly active composite sites for catalyzing the ORR in an acid medium.

5.
Chem Biodivers ; 19(10): e202200444, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36066484

RESUMO

Callicarpa nudiflora, belonging to the family Verbenaceaae, is wildly used as a traditional Chinese herbal medicine (Luo-hua-zi-zhu) for hemostasis, antibiosis and antiphlogosis in clinic. However, the underlying chemical basis of C. nudiflora for the significant effects remains obscure. Hence, an ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry method was established for the characterization of multi-constituents in C. nudiflora. As a result, 57 chemical compounds were identified based on their retention times, accurate masses and MS/MS data, and 20 of them were uncovered for the first time in C. nudiflora. In addition, an optimized UHPLC fingerprint analysis, combined with chemometrics including similarity analysis, principal component analysis and partial least squares-discriminant analysis was developed for quality assessment and origin discrimination of C. nudiflora. Multivariate data analysis revealed the resemblances and differences of C. nudiflora related to regions, while partial least squares-discriminant analysis screened nine characteristic markers including luteoloside, acteoside, luteolin-4'-O-ß-D-glucopyranoside, pachypodol, isoquercitrin, nudifloside, 5,7,3',4'-tetrahydroxy-8-methoxy-6-C-ß-D-glucopyranosylflavone, 7α-acetoxysandaracopimaric acid and sandaracopimaric acid which contributed the most to the classification. This was the first report on the comprehensive profiling of chemical components in C. nudiflora, which helped to uncover the material basis of C. nudiflora and possess potential value for quality evaluation and clinical application purpose.


Assuntos
Callicarpa , Medicamentos de Ervas Chinesas , Callicarpa/química , Espectrometria de Massas em Tandem , Luteolina , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química
6.
Zhongguo Zhong Yao Za Zhi ; 45(8): 1800-1807, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32489063

RESUMO

The difference in pharmacological activities and active components between leaves, barks and flowers of Eucommia ulmoides(EU) are still unclear. However, clarifying the differences in pharmacological effects of different parts of EU is of great significance for the development of EU products, and their corresponding active components provide basis for quality control of different parts of EU. Based on the chemical compositions of different parts of EU, integrated strategy of target prediction and target analysis of the compounds was used to investigate the difference in the pharmacological effects of leaves, barks and followers. The "component-target-function" association network was constructed to mine the specific material basis corresponding to specific efficacy of different parts of EU. In this study, the author found that EU may have the activities of anti-oxidation, neuromodulation, blood pressure regulation, myo-cardial expansion, and anti-apoptosis according to target prediction and function analysis. However, the effects of different parts of EU were different. Leaves were involved in the process of bone development such as osteoblast differentiation and bone mineralization in a specific way. In addition, the leaves may affect the process of bone development by regulating the metabolism of vitamin D and affecting the absorption of calcium. Leaves may also specifically act on estrogen and estradiol response processes where estrogen receptors were involved. Regarding its protective function for the liver, leaves may play a role by regulating vitamin A-related pathways. As compared with leaves, the specific pharmacological effects of barks may be related to the development of the urinary system. Flowers specifically participate in functions related to pain sensation, glutamate signaling pathway, and excitatory postsynaptic potential. Based on the hie-rarchical network of "component-target-pathway", we further found that specific activities of different parts of EU were inseparable from its specific chemical compositions. Phenylpropanoids, terpenoids and rings, iridoids, flavonoids and other components which are specific in leaves can target the specific effects of leaves, while the flavonoids in barks and the quinones in flowers may be the material basis for their respective specific effects. The prediction of the activities of different parts of EU provides a new basis for the focuses and differences in subsequent Eucommia product development. At the same time, the material basis research based on differential efficacy also provides a basis for the quality control of Eucommia differentiated products.


Assuntos
Eucommiaceae , Preparações Farmacêuticas , Flavonoides , Iridoides , Folhas de Planta
7.
Zhongguo Zhong Yao Za Zhi ; 45(3): 497-512, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237506

RESUMO

To date, 205 compounds have been identified from different medicinal parts of Eucommia ulmoides, including lignans, iridoid terpenoids, phenols, flavonoids, terpenoids and steroids, polysaccharides and others. Their pharmacological effects include blood pressure-lowering, blood sugar-lowering, blood lipids-regulating, prevention of osteoporosis, anti-inflammation, liver protection, anti-cancer and so on. Their efficacy and mechanism from different parts are slightly different. In this paper, the chemical composition, pharmacological action and mechanism of different parts of E. ulmoides were systematically summarized, as well as its quality control and processing research, to provide theoretical basis for further rational development and utilization of E. ulmoides.


Assuntos
Eucommiaceae/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Flavonoides , Iridoides , Lignanas , Fenóis , Plantas Medicinais/química , Polissacarídeos , Esteroides , Terpenos
8.
Ecotoxicol Environ Saf ; 183: 109471, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377520

RESUMO

Present study described a magnetic adsorption and removal method with prepared magnetic core-shell Fe3O4@polyaniline microspheres for the removal of two typical BFRs, tetrabromobisphenol-A (TBBPA) and decabromodiphenyl ether (BDE-209) from water samples. Magnetic core-shell Fe3O4@polyaniline microspheres were prepared by a hydrothermal and two step polymerization method with cheap iron salts and aniline, which were characterized with transmission electron microscopic (TEM) and scanning electron microscopy (SEM). The results showed that the Fe3O4@polyaniline microspheres earned a clear thickness shell of polyaniline (about 50 nm) and a saturation magnetization of 40.4 emu g-1. The Magnetic core-shell Fe3O4@polyaniline exhibited excellent adsorption capability and removal rate to TBBPA and BDE 209. The adsorption of TBBPA and BDE 209 all followed pseudo-second order kinetics and agreed well to the Freundlich adsorption isotherms model. The negative Gibbs free energy change (ΔG0) and positive standard enthalpy change (ΔH0) for TBBPA and BDE-209 suggested that the adsorption was spontaneous and endothermic in nature. These results demonstrated that Fe3O4@PANI was a good adsorbent and would have a good application prospect in the removal of pollutants from environmental water.


Assuntos
Compostos de Anilina/química , Éteres Difenil Halogenados/análise , Nanopartículas de Magnetita/química , Nanocompostos/química , Bifenil Polibromatos/análise , Purificação da Água/métodos , Adsorção , Cinética , Água , Poluentes Químicos da Água/análise
9.
Anal Bioanal Chem ; 408(19): 5211-20, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27178558

RESUMO

In this work, polyethyleneimine grafted silica-coated nanoscale zero valent iron (Fe@SiO2@PEI) has been successfully synthesized and was investigated to be an effective adsorbent for efficient enrichment of five phthalate esters such as diphenyl phthalate, dibenzyl phthalate, butyl benzyl phthalate, diphenyl isophthalate, and dicyclohexyl phthalate (DPP, DBP, BBP, DPIP, and DCHP) from environmental water samples. The structure and morphology of the materials were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction(XRD). The parameters that influenced the enrichment performance such as amount of sorbent, sample pH, type of eluent, volume of eluent, salting-out effect, adsorption time, and desorption time were investigated. Under optimal conditions, excellent linear relationships were found in the concentration range from 0.5 to 100 µg L(-1), the limits of detection (S/N = 3) were in the range of 0.26-0.45 µg L(-1), and the intra-day and inter-day precisions (n = 6) were in the range of 3.7-4.8 and 3.2-4.3 %, respectively. The developed method was evaluated with real water samples, and satisfied spiked recoveries in the range of 99-104 % were achieved. The experimental results proved that Fe@SiO2@PEI had good adsorption for phthalate esters, and would be a good adsorbent for the magnetic solid-phase extraction of important pollutants from environmental water samples.ᅟ Graphical abstract A flowchart of the synthesis of polyethyleneimine grafted silica coated nanoscale zero valent iron (Fe@SiO2@PEI) and the process of the developed magnetic solid phase extraction of phthalate esters before the analysis by high performance liquid chromatography.

10.
Chemosphere ; 361: 142535, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38844108

RESUMO

Antibiotics are widely used in clinical medicine due to their excellent antibacterial abilities. As typical emerging pollutants, their misuse can lead to excess antibiotics entering the environment, causing antimicrobial resistance and leading to serious health problems via food chain. Herein, a nano-fluorescent probe based on nitrogen-doped carbon dots (N-CDs) was constructed for the sensitive detection of chlortetracycline (CTC). N-CDs with stable fluorescence were synthesized by hydrothermal method using alizarin red and melamine as raw materials. The N-CDs exhibited significant independence to excitation wavelength. The fluorescence of N-CDs was significantly quenched by CTC ascribing to the fluorescence resonance energy transfer mechanism. The concentration of N-CDs, solution pH and incubation time were optimized to obtain the optimal detection parameters. Under optimal conditions, CTC exhibited excellent linearity over the range of 20-1200 µg/L, and the detection limit was 8.74 µg/L. The method was validated with actual water samples and achieved satisfied spiked recoveries of 97.6-102.6%. Therefore, the proposed method has significant application value in the detection of CTC in waters.


Assuntos
Antibacterianos , Carbono , Clortetraciclina , Corantes Fluorescentes , Limite de Detecção , Nitrogênio , Pontos Quânticos , Poluentes Químicos da Água , Clortetraciclina/análise , Nitrogênio/química , Nitrogênio/análise , Carbono/química , Corantes Fluorescentes/química , Poluentes Químicos da Água/análise , Pontos Quânticos/química , Antibacterianos/análise , Transferência Ressonante de Energia de Fluorescência , Fluorescência
11.
J Pharm Biomed Anal ; 246: 116198, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38754154

RESUMO

With the aging of the population, the prevalence of osteoporosis (OP) is rising rapidly, making it an important public health concern. Early screening and effective treatment of OP are the primary challenges facing the management of OP today. Quanduzhong capsule (QDZ) is a single preparation composed of Eucommia ulmoides Oliv., which is included in the Pharmacopoeia of the People's Republic of China. It is used to treat OP in clinical practice, but its mechanisms are unclear. This study involved 30 patients with OP, 30 healthy controls (HC), and 28 OP patients treated with QDZ to identify potential biomarkers for the early diagnosis of OP and to investigate the potential mechanism of QDZ in treating OP. The serum samples were analyzed using targeted amino acid metabolomics. Significant differences in amino acid metabolism were identified between the OP cohort and the HC group, as well as between OP patients before and after QDZ treatment. Compared with HC, the serum levels of 14 amino acids in OP patients changed significantly. Kynurenine, arginine, citrulline, methionine, and their combinations are expected to be potential biomarkers for OP diagnosis. Notably, QDZ reversed the changes in levels of 10 amino acids in the serum of OP patients and significantly impacted numerous metabolic pathways during the treatment of OP. This study focuses on screening potential biomarkers for the early detection of OP, which offers a new insight into the mechanism study of QDZ in treating OP.


Assuntos
Aminoácidos , Biomarcadores , Medicamentos de Ervas Chinesas , Metabolômica , Osteoporose , Humanos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Biomarcadores/sangue , Metabolômica/métodos , Osteoporose/sangue , Osteoporose/tratamento farmacológico , Feminino , Pessoa de Meia-Idade , Masculino , Aminoácidos/sangue , Idoso , Cápsulas , Eucommiaceae , Estudos de Casos e Controles , Adulto
12.
NanoImpact ; 31: 100478, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37499754

RESUMO

Due to the growing number of the world's population, there is an urgent need for high-quality food to meet global food security. Traditional fertilizers and pesticides face the problems of low utilization efficiency and possible hazards to non-target organisms. Selenium (Se) is an essential trace element for animals and humans. As a result, Se nanoparticles (SeNPs) have aroused intense interest and found opportunities in agricultural use. Herein, we summarized representative studies on the potential application of SeNPs in agriculture, including mitigating biotic and abiotic stresses in plants, promoting seed germination and plant growth, and improving Se contents and nutritional values in crops, and the underlying mechanisms were also discussed. Finally, future directions are highlighted to get a deep insight into this field.

13.
ACS Omega ; 8(49): 46589-46597, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107970

RESUMO

Hydroxyl (OH) radicals, as common radicals in aqueous environments, play an important role in inducing the degradation reactions of polymers. However, understanding the fundamental mechanisms of radical-induced degradation of polymers at the atomic level remains a formidable challenge. In this study, we employ density functional theory to investigate the geometric and electronic structural properties of polyacrylamide (PAM) in (-CH2CHCONH2-)n (n = 2-6) complexes. Additionally, we explore the degradation mechanism of the n = 4 complex induced by the OH radical. The results indicate that there are three sites for the initial reaction (R1 and R2 are at the ends and R3 is in the middle). The OH radical removes a H atom from the PAM main chain and simultaneously triggers a single-electron-transfer process on the same chain. This process significantly reduces the dissociation energy barrier of the C-C bond in the PAM chain, from ∼90 to ∼20 kcal/mol. Specifically, when the induced reaction occurs at the end of the chain, a series of broken bonds will appear only along the main chain. While it happens in the middle, the broken bonds will exist simultaneously along both the main and side chains. Our results reveal the importance of OH radicals in polymer dissociation, particularly in PAM, and emphasize the degradation mechanism of SET.

14.
Nat Prod Res ; : 1-8, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38031803

RESUMO

Callicarpa nudiflora (C. nudiflora) is widely used in the treatment of bleeding related diseases. However, its main material basis has not been fully defined which limits the in-depth study of screening out the material basis of hemostasis and coagulation from C. nudiflor. In this study, the method of spectrum-effect relationship was used to quickly screen the material basis of hemostasis and coagulation. The five compounds related to hemostasis and coagulation were screened as Alyssonoside (P24), Luteolin (P25), Quercetin (P26), Apigenin (P28), Isorhamnetin (P29). And the contribution of these five peaks to hemostasis and coagulation efficacy was P24 > P25 > P28 > P26 > P29.

15.
J AOAC Int ; 95(5): 1534-40, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23175990

RESUMO

This paper reports a new method for the determination of aromatic amines with temperature-controlled ionic liquid dispersive liquid-phase microextraction in combination with HPLC and results of investigation of the influence of anions in ionic liquids on the extraction performance. In these experiments, 1-octyl-3-methylimidazolium hexafluorophosphate ([C8MIM][PF6]), 1-octyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide ([C8MIM][NTf2]), and 1-octyl-3-methylimidazolium tetrafluoroborate ([C8MIM][BF4]) were used as the extraction solvents for the investigation of the effect of anions in ionic liquids. Other parameters affecting the microextraction performance were also investigated. Under the optimal conditions, the proposed method had good linearity over the concentration ranges of 1.0-100 microg/L for 2, 4-dimethylaniline, 2-chloroanline, and N,N-dimethylaniline, and 1.5-150 microg/L for N,N-dimethylaniline and alpha-naphthylamine, with excellent correlation coefficients (R2 > or = 0.999), excellent detection sensitivity with LODs (S/N = 3) in the range of 0.39-0.63 microg/L, and precision in the range of 3.2-5.4% RSD (n = 6). Real water samples were analyzed with the established method, and good spike recoveries in the range of 86.3 to 98.9% were obtained. These results indicated that this method would be useful in the routine analysis of such pollutants.


Assuntos
Aminas/química , Líquidos Iônicos/química , Microextração em Fase Líquida/métodos , Poluentes Químicos da Água/química , Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , Temperatura , Fatores de Tempo , Água/química
16.
Anal Methods ; 14(6): 672-677, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35088063

RESUMO

The sensitive determination of the critical micelle concentration (CMC) of surfactants is very important for their practical application. Due to their good sensitivity and simple operation, pyrene and its derivatives have been widely used as fluorescent probes to detect the CMC. However, their virulent and poor water-soluble nature has limited their wide employment. In the present work, environmentally friendly amphiphilic carbon dots (Cdots) with dual-color emission and absolute quantum yield (PLQY) values higher than 50% have been fabricated through a solvothermal process, which could successfully serve as self-calibrative, ratiometric fluorescent probes to estimate the CMC of both non-ionic and ionic surfactants. This work not only provides a new strategy to design green ratiometric fluorescent probes for the CMC measurement of surfactants but also expands the application of Cdots in the colloidal field.


Assuntos
Carbono , Pontos Quânticos , Corantes Fluorescentes , Micelas , Tensoativos
17.
J Pharm Pharmacol ; 74(11): 1598-1608, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36106815

RESUMO

Objectives Due to its high morbidity, high mortality, and high disability, stroke has been the first cause of death and the major cause of adult disability in China. Natural borneol has been widely utilized in Traditional Chinese Medicine to promote drug absorption. Formononetin is a natural isoflavonoid with potent neuroprotective activity but poor brain delivery. Methods This study aimed to screen the optimum proportion that natural borneol promotes formononetin entry into the brain, evaluate the anti-cerebral ischaemia efficacy of formononetin/natural borneol combination in middle cerebral artery occlusion/reperfusion model rats, and clarify the possible mechanism for natural borneol's promoting formononetin delivery in the brain. Key findings Our studies exhibited that natural borneol remarkably promoted formononetin entry into the brain when combined with formononetin in a 1 : 1 molar ratio and notably improved neuro-behavioural scores and reduced the infarct of middle cerebral artery occlusion/reperfusion model rats. This study further discovered that the enhanced anti-cerebral ischaemia effect resulted from natural borneol increasing the permeability of the blood-brain barrier to elevate formononetin concentration in the brain rather than the pharmacodynamic synergy or addition between formononetin and natural borneol. Conclusions The study provides a good strategy to screen drug combinations for the treatment of brain disease by combining natural borneol with other drugs.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Animais , Ratos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Canfanos/farmacologia , Isquemia Encefálica/tratamento farmacológico , Encéfalo , Traumatismo por Reperfusão/tratamento farmacológico
18.
Analyst ; 136(13): 2741-6, 2011 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-21607284

RESUMO

This paper described a new method for the enrichment and determination of pyrethroid pesticides from environmental water samples with ordered TiO(2) nanotube array micro-solid phase equilibrium extraction (µ-SPEE) prior to gas chromatography (GC) with electron capture detection (ECD). Several factors such as the anodization voltage, the kind of organic solvents, sample pH, equilibrium extraction time, desorption time and salting-out effect were optimized. Under the optimal conditions, ordered TiO(2) nanotube arrays demonstrated excellent merits on the preconcentration of pyrethroid pesticides and good detection limits were achieved as 0.018, 0.020, 0.031, 0.041, and 0.070 µg L(-1) for bifenthrin, fenpropathrin, cyhalothrin, fenvalerate, and deltamethrin, respectively. Four real water samples were used to validate the proposed method and the spiked recoveries were over the range of 81.9-110.6%. Compared to conventional solid phase extraction (SPE), the present method showed better recoveries and good reproducibility. These results showed that this µ-SPEE technique could be an important alternative to multistep SPE for the extraction and determination of such analytes in complex samples and become a useful tool in monitoring such analytes in the environment.

19.
Anal Bioanal Chem ; 400(1): 205-12, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21344165

RESUMO

Ordered TiO(2) nanotube arrays have been widely used in many fields such as photocatalysis, self-cleaning, solar cells, gas sensing, and catalysis. This present study exploited a new functional application of the ordered TiO(2) nanotube arrays. A micro-solid phase equilibrium extraction using ordered TiO(2) nanotube arrays was developed for the enrichment and measurement of organochlorine pesticides prior to gas chromatography-electron capture detection. Ordered TiO(2) nanotube arrays exhibited excellent merits on the pre-concentration of organochlorine pesticides and lower detection limits of 0.10, 0.10, 0.10, 0.098, 0.0076, 0.0097, 0.016, and 0.023 µg L(-1) for α-HCH, ß-HCH, γ-HCH, δ-HCH, p,p'-DDE, p,p'-DDD, o,p'-DDT, and p,p'-DDT, respectively, were achieved. Four real water samples were used for validation, and the spiked recoveries were in the range of 78-102.8%. These results demonstrated that the developed micro-solid phase equilibrium extraction using ordered TiO(2) nanotube arrays would be very constructive and have a great beginning with a brand new prospect in the analysis of environmental pollutants.


Assuntos
Hidrocarbonetos Clorados/análise , Nanotubos , Praguicidas/análise , Titânio/química , Poluentes Químicos da Água/análise , Cromatografia Gasosa , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes
20.
Front Pharmacol ; 12: 806808, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35153761

RESUMO

Callicarpa nudiflora (C. nudiflora) is widely used to treat inflammation-related diseases in China. C. nudiflora mainly contains phenylethanol glycosides, flavonoids, triterpenes, diterpenes, iridoid glycosides, volatile oils, and other small molecules. Therefore, it is necessary to screen out anti-inflammatory active substances from C. nudiflora. In this paper, high-performance liquid chromatography was used to establish the fingerprint of C. nudiflora extracts. The anti-inflammation of C. nudiflora extracts were evaluated by the experiment of toes swelling in inflammatory rats. Then, the spectrum-effect relationship between the fingerprints and anti-inflammatory activities was researched by Pearson analysis and orthogonal partial least squares analysis to identify a group of anti-inflammatory compounds of C. nudiflora extracts. The differences of extracts are illustrated by principal component analysis and cluster analysis in pharmacological effects. Finally, 12 compounds, including catalpol (P1), caffeic acid (P2), protocatechuic acid (P9), 3,4-dihydroxybenzaldehyde (P10), forsythiaside E (P12), protocatechualdehyde isomers (P14), forsythiaside B (P15), rutin (P16), alyssonoside (P21), verbascoside (P22), 2'-acetyl forsythoside B (P24), and isorhamnetin (P32) by HPLC-DAD and UPLC-Q-TOF MS/MS, were determined as potential compounds for anti-inflammatory activity in C. nudiflora. In particular, six compounds were identified as active substances with the greatest anti-inflammatory potential. Moreover, all compounds were tested for anti-inflammatory experiments or anti-inflammatory literature retrieval. In this study, a method for rapid screening of potential anti-inflammatory active ingredients of C. nudiflora was established, which can provide a reference for the future study of active compounds of C. nudiflora.

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