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1.
Artigo em Inglês | MEDLINE | ID: mdl-38922561

RESUMO

The resistance of malignant tumors to multiple drugs is a significant obstacle in cancer treatment and prognosis. Accordingly, we synthesized a celastrol (Cel) prodrug (Cel-CSO) by conjugating chitosan oligosaccharides (CSO) to Cel for reversing Taxol resistance in chemotherapy, followed by self-assembly with Taxol into a novel nanoplatform of Cel-CSO/Taxol nanoparticles (termed NPs). NPs showed a suitable size (about 153 nm), excellent stability and prolonged release of Cel and Taxol in a manner that depended on both pH and time. NPs effectively inhibited the overexpression of multidrug resistance-related protein P-gp, hypoxia inducible factor-1α (HIF-1α), and triggered the MCF-7/Taxol cell apoptosis through inhibiting the PI3K/AKT/NF-κB/HIF-1α pathway. In tumor-bearing mice, NPs exhibited significant curative effects in inducing apoptosis of MCF-7/Taxol tumors which showed a low expression level of P-gp, microtubule-related proteins TUBB3 and Tau. The results indicated that NPs may be a promising strategy to overcome drug resistance caused by P-gp, which improve the antitumor effects in drug-resistant breast cancer.

2.
Talanta ; 277: 126344, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38838562

RESUMO

A magnetic MXene aerogel (Fe3O4@MXene@PEI) was prepared by crosslinking amino modified MXene with polyethyleneimine using epichlorohydrin as a cross-linker. Adsorption properties of Fe3O4@MXene@PEI aerogel for phenolic acids were evaluated by adsorption kinetics and isotherms experiments, showing that the high adsorption affinity was governed by multilayer chemisorption process. An efficient MSPE/HPLC method was developed for the determination of phenolic acids with excellent selectivity, good linearity (0.025-5.0 µg mL-1), low LODs (0.007-0.017 µg mL-1), and satisfactory recoveries (80.0-120.0 %). Moreover, the antioxidant activity of the Fe3O4@MXene@PEI purified compounds was superior to that of the conventional method as demonstrated by the results of scavenging experiments on 2,2 -diphenyl-1-picrylhydrazyl radical scavenging assay. Finally, 65 organic acids were identified in the Fe3O4@MXene@PEI treated honeysuckle extracts by UHPLC-Q-Exactive Orbitrap MS/MS analysis. The proposed sorbent exhibits remarkable promise for the selective separation and purification of organic acids from herbal products.

3.
Chem Res Toxicol ; 37(6): 944-956, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38771988

RESUMO

Celastrol (Cel), extracted from Tripterygium wilfordii Hook, is a potential antiobesity drug, except for its adverse reactions in clinic. In the present study, we synthesized a promising celastrol-chitosan conjugate (Cel-CS1K) and evaluated its antiobesity effect and biological safety in diet-induced obese mice. Cel-CS1K showed higher drug loading (over 10 wt %), good solubility (18-19 mg/mL) in water, slower peak time (Tmax = 4 h), and clearance (T1/2 = 8.97 h) in rats. Cel-CS1K effectively attenuated the cytotoxicity, celastrol-induced apoptosis, and fat accumulation of hepatocytes. Cel-CS1K reduced body weight and dietary amount same as the free Cel but with lower toxicity in blood, liver, and testis. Cel-CS1K improved the glucose homeostasis, HDL-C level, insulin sensitivity, and leptin sensitivity, while it significantly reduced the gene expression levels of LDL-C, TG, and TC in obese mice. Furthermore, the adipose-related gene expression levels provided evidence in support of a role for Cel-CS1K in losing weight by the multimode regulation. Overall, Cel-CS1K provides a translatable therapeutic strategy for the treatment of diet-induced obese humans.


Assuntos
Fármacos Antiobesidade , Quitosana , Obesidade , Triterpenos Pentacíclicos , Triterpenos , Animais , Triterpenos Pentacíclicos/farmacologia , Triterpenos Pentacíclicos/química , Obesidade/tratamento farmacológico , Masculino , Triterpenos/química , Triterpenos/farmacologia , Camundongos , Quitosana/química , Quitosana/farmacologia , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/química , Ratos , Dieta Hiperlipídica/efeitos adversos , Humanos , Ratos Sprague-Dawley , Camundongos Endogâmicos C57BL , Apoptose/efeitos dos fármacos , Tripterygium/química
4.
Zhongguo Fei Ai Za Zhi ; 27(3): 216-230, 2024 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-38590196

RESUMO

Non-small cell lung cancer (NSCLC) is one of the malignant tumors with high morbidity and mortality worldwide. Ferroptosis is a new type of programmed cell death caused by abnormal accumulation of iron-dependent reactive oxygen species (ROS) leading to lipid peroxidation. It involves the balance between iron metabolism, lipid metabolism, oxygen free radical reaction and lipid peroxidation. Recent studies have found that ferroptosis is closely related to the occurrence and development of NSCLC. Due to the emergence of chemotherapy resistance and radiotherapy resistance in the treatment of NSCLC, there is an urgent need to develop new effective drugs and treatment strategies. Traditional Chinese medicine has unique advantages in the prevention and treatment of NSCLC due to its multi-targets and minimal side effects. In this review, we summarize the mechanism of ferroptosis in NSCLC, and discuss the research status of active ingredients of traditional Chinese medicine, single-herb traditional Chinese medicine and Chinese herbal compounds in the intervention of NSCLC through ferroptosis, in order to provide a new theoretical basis for the research of ferroptosis pathway and the prevention and treatment of NSCLC by targeted ferroptosis of traditional Chinese medicine.
.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Ferroptose , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Medicina Tradicional Chinesa , Neoplasias Pulmonares/tratamento farmacológico , Ferro
5.
J Sep Sci ; 47(1): e2300620, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38066235

RESUMO

Herein, a magnetic borate-functionalized MXene composite with multiple boronic affinity sites was fabricated by embedding Fe3 O4 nanoparticles with 4-formylphenylboronic acid functionalized Ti3 C2 Tx nanosheets and served as sorbent for the simultaneous extraction of catecholamines (CAs) in urine samples. The morphology and structure of the magnetic materials were investigated using scanning microscopy, vibrating sample magnetometer, X-ray photoelectron spectrometer, and X-ray diffraction. The introduction of polyethyleneimine can amplify the bonded boronic acid groups, thereby effectively improving the adsorption capacities for CAs based on the multiple interactions of boronic affinity, hydrogen bonding, and metal coordination. The adsorption performance was investigated using the kinetics and isotherms models, and the main parameters that influence the extraction efficiency were optimized. Under the most favorable magnetic solid-phase extraction condition, a sensitive method for the analysis of CAs in urine samples was developed by combining magnetic solid-phase extraction conditions with high-performance liquid chromatography detection. The findings illustrated that the proposed approach possessed a wide linearity range of 0.05-250 ng/mL with an acceptable correlation coefficient (R2  ≥ 0.9984) and detection limits of 0.010-0.015 ng/mL for the target CAs. The research not only provides a notable composite with multiple boronic affinity sites but also offers an effective and feasible measure for the detection of CAs in biological samples.


Assuntos
Catecolaminas , Nanopartículas de Magnetita , Nitritos , Elementos de Transição , Polietilenoimina/química , Adsorção , Ácidos Borônicos/química , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida , Nanopartículas de Magnetita/química , Fenômenos Magnéticos
7.
Eur J Med Chem ; 259: 115679, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37517203

RESUMO

Stachydrine is a hydrophilic quaternary amine salt with good antitumor effect, but its application is limited due to its rapid metabolism and low bioavailability. We synthesized and evaluated nine prodrugs of stachydrine, which showed suitable hydrophobicity (CLogP: -2.58-4.78, vs SS-0: -3.32) and better in vitro anticancer activity (IC50: 0.34 µM-14.03 mM, vs SS-0: 38.97 mM-147.19 mM) in comparison with stachydrine. Among them, SS-12, SS-16 and SS-18 are the most effective compounds against 4T1 cells, and the IC50 is 2.15-24.14 µM. Especially, compared with stachydrine, SS-12 significantly blocked the cell cycle in the G0/G1 phase, reduced the mitochondrial membrane potential, and induced the apoptosis of 4T1 cells through mitochondria pathway, which increased the expressions of Bax and cleaved caspase-3 protein, decrease the expression of Bcl-2. The pharmacokinetics of SS-12 showed a rational bioavailability (79.6%), and a longer retention time (T1/2 = 7.62 h) than that of stachydrine (T1/2 ≈ 1.16 h) in rats. Compared with stachydrine, SS-12 significantly enhanced the anticancer efficacy (56.32% of tumor-inhibition rates, vs SS-0: 3.89%), meanwhile, ameliorated the tumor-induced organ damage in mice. Therefore, SS-12 may be a promising prodrug of stachydrine against breast cancer.


Assuntos
Antineoplásicos , Neoplasias , Ratos , Animais , Camundongos , Linhagem Celular Tumoral , Fase G1 , Ciclo Celular , Prolina/farmacologia , Apoptose , Proliferação de Células , Antineoplásicos/farmacologia
8.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2426-2434, 2023 May.
Artigo em Chinês | MEDLINE | ID: mdl-37282872

RESUMO

Tripterygium glycosides liposome(TPGL) were prepared by thin film-dispersion method, which were optimized accor-ding to their morphological structures, average particle size and encapsulation rate. The measured particle size was(137.39±2.28) nm, and the encapsulation rate was 88.33%±1.82%. The mouse model of central nervous system inflammation was established by stereotaxic injection of lipopolysaccharide(LPS). TPGL and tripterygium glycosides(TPG) were administered intranasally for 21 days. The effects of intranasal administration of TPG and TPGL on behavioral cognitive impairment of mice due to LPS-induced central ner-vous system inflammation were estimated by animal behavioral tests, hematoxylin-eosin(HE) staining of hippocampus, real-time quantitative polymerase chain reaction(RT-qPCR) and immunofluorescence. Compared with TPG, TPGL caused less damage to the nasal mucosa, olfactory bulb, liver and kidney of mice administered intranasally. The behavioral performance of treated mice was significantly improved in water maze, Y maze and nesting experiment. Neuronal cell damage was reduced, and the expression levels of inflammation and apoptosis related genes [tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1ß), BCL2-associated X(Bax), etc.] and glial activation markers [ionized calcium binding adaptor molecule 1(IBA1) and glial fibrillary acidic protein(GFAP)] were decreased. These results indicated that liposome technique combined with nasal delivery alleviated the toxic side effects of TPG, and also significantly ameliorated the cognitive impairment of mice induced by central nervous system inflammation.


Assuntos
Glicosídeos Cardíacos , Disfunção Cognitiva , Camundongos , Animais , Tripterygium , Lipossomos , Glicosídeos/uso terapêutico , Administração Intranasal , Lipopolissacarídeos , Sistema Nervoso Central , Disfunção Cognitiva/tratamento farmacológico , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
J Sep Sci ; 46(14): e2300131, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37246279

RESUMO

In this study, a borate hyper-crosslinked polymer was synthesized by crosslinking 1-naphthalene boric acid and dimethoxymethane via the Friedel-Crafts reaction. The prepared polymer exhibits excellent adsorption performance toward alkaloids and polyphenols with maximum adsorption capacities ranging from 25.07 to 39.60 mg/g. Adsorption kinetics and isotherms model results indicated the adsorption was a monolayer and chemical process. Under the optimal extraction conditions, a sensitive method was established for the simultaneous quantification of alkaloids and polyphenols in green tea and Coptis chinensis by coupling with the proposed sorbent and ultra-high performance liquid chromatography detection. The proposed method exhibited a wide linear range of 5.0-5000.0 ng/ml with R2 ≥ 0.99, a low limit of detection (0.66-11.25 ng/ml), and satisfactory recoveries (81.2%-117.4%). This work provides a simple and convenient candidate for the sensitive determination of alkaloids and polyphenols in green tea and complex herbal products.


Assuntos
Alcaloides , Boratos , Boratos/análise , Polímeros/química , Polifenóis/análise , Extração em Fase Sólida/métodos , Alcaloides/análise , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Chá , Limite de Detecção
10.
Zhongguo Zhong Yao Za Zhi ; 47(20): 5574-5583, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36471975

RESUMO

Histone lysine-specific demethylase 1(LSD1) has become a promising molecular target for lung cancer therapy. Upon the screening platform for LSD1 activity, some Chinese herbal extracts were screened for LSD1 activity inhibition, and the underlying mechanism was preliminarily investigated at both molecular and cellular levels. The results of LSD1 inhibition showed that Puerariae Lobatae Radix extract can effectively reduce LSD1 expression to elevate the expression of H3 K4 me2 and H3 K9 me2 substrates in H1975 and H1299 cells. Furthermore, Puerariae Lobatae Radix was evaluated for its anti-lung cancer activity. It had a potent inhibitory ability against the proliferation and colony formation of both H1975 and H1299 cells. Flow cytometry and DAPI staining assays indicated that Puerariae Lobatae Radix can induce the apoptosis of lung cancer cells. In addition, it can significantly suppress the migration and reverse the epithelial-mesenchymal transition(EMT) process of lung cancer cells by activating E-cadherin and suppressing the expression of N-cadherin, slug and vimentin. To sum up, Puerariae Lobatae Radix displayed a robust inhibitory activity against lung cancer, and the mechanism may be related to the down-regulation of LSD1 expression to induce the cell apoptosis and suppress the cell migration and EMT process. These findings will provide new insights into the action of Puerariae Lobatae Radix as an anti-lung cancer agent and offer new ideas for the study on the anti-cancer action of Chinese medicine based on the epigenetic modification.


Assuntos
Neoplasias , Pueraria , Pueraria/química , Histona Desmetilases/genética , Histona Desmetilases/análise , Raízes de Plantas/química , Transição Epitelial-Mesenquimal
11.
Molecules ; 27(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36432100

RESUMO

A series of co-crystals of ascorbic acid were prepared with equimolar amounts of co-crystal formers (CCFs), including isonicotinic acid, nicotinic acid, 3,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid and m-hydroxybenzoic acid, by slow solvent evaporation and solvent-assisted grinding. The co-crystals were characterized by single-crystal X-ray diffraction spectroscopy, powder X-ray diffraction, IR spectroscopy, differential scanning calorimetry and thermogravimetric analysis. Molecular dynamics (MD) simulations further validated the interaction energy and the possible intermolecular hydrogen bonds among VC and CCFs. The co-crystals showed improved stability when exposed to different wavelengths of light, pH and temperatures compared to the free analogue, especially at higher pH (~9) and lower temperature (~4 °C).


Assuntos
Ácido Ascórbico , Niacina , Pós , Varredura Diferencial de Calorimetria , Solventes
12.
Front Chem ; 10: 951434, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212077

RESUMO

Liposome is a conventional drug delivery system which has been widely used in the pharmacy field. However, its applications are greatly restricted in clinical practice by the disadvantages of cholesterol and nonselective distribution. Herein, a novel platform for anti-tumor drug delivery was developed by incorporating an amphiphilic stachydrine-octadecane conjugate (SS) as the mitochondria-targeting molecule onto the triptolide-liposome surfaces (SS-TP LPs). The polyethylene glycol (PEG) and the suitable particle size (about 133 nm) of liposomes facilitated their stabilities, the long half-life in blood and the escape from the rapid elimination. The SS-TP LPs were internalized and accumulated into the mitochondria of cancer cells in a time-dependent manner, followed by triggering permeabilization of the mitochondrial outer membrane by inhibiting Bcl-2, and then further caused greater cancer cell death via releasing cytochrome C and initiating a cascade of caspase 3 reactions. In the Pan02 tumor-bearing mice, the SS-TP LPs showed significant efficacy in inhibiting tumor growth and reducing tumor size but synchronously exhibited specific mitochondria-targeting and much lower subacute toxicity compared with the free TP and TP LPs. Our study suggests that SS-TP LPs can be a promising anticancer drug delivery system for mitochondria-targeted therapy in pancreatic cancer.

13.
Drug Deliv ; 29(1): 2751-2758, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35999774

RESUMO

Triptolide (TP) has its unique curative effect in the treatment of rheumatoid arthritis (RA), but its application is limited by the poor water solubility and multi-organ toxicity. We herein developed a novel nanoparticle platform composed of L-ascorbate palmitate (VP, vitamin C derivative) that can deliver TP to synergistically treat arthritis and inhibit the occurrence of oxidative stress. The TP-loaded nanoparticles (termed TP-VP NPs) showed the suitable particle size (about 145 nm) and good physical stability. TP-VP NPs effectively down-regulated IL-1ß, IL-6 and TNF-α levels to inhibit the erosion of synovitis and bone tissue, and alleviate the swelling and deformation of CIA mice's feet. Compared to the TP, TP-VP NPs could inhibit effectively the oxidative stress in liver, and alleviate significantly the triptolide-induced toxicity injury in liver, kidney and testicle. The results demonstrated that TP-VP NPs is a promising triptolide delivery system for the treatment of RA, which enhances the water solubility of TP and reduces the toxicity of TP in vivo.


Assuntos
Artrite Reumatoide , Diterpenos , Fenantrenos , Animais , Artrite Reumatoide/induzido quimicamente , Artrite Reumatoide/tratamento farmacológico , Ácido Ascórbico , Diterpenos/farmacologia , Compostos de Epóxi , Camundongos , Micelas , Palmitatos/uso terapêutico , Fenantrenos/farmacologia , Água
14.
Front Pharmacol ; 13: 908227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814255

RESUMO

Clinical use of triptolide (TP) is restricted due to severe toxicity. This study assessed the protective effect of crocin (CR) as a natural antioxidant against TP-induced toxicity in bovine collagen type II-induced arthritis (CIA) in mice. The mice in the CIA model group showed macroscopic signs of severe arthritis. The anti-arthritis effects in the control, TP + CR, and TP groups were evaluated through assessment of foot volume, arthritis score, and proinflammatory cytokines, and collagen antibody assay. Crocin reduced TP-induced toxicity, as evidenced by evaluation of survival rate, body weight, visceral index, hepatic and renal functions, histopathologic analyses, and antioxidant enzyme activities. Transcriptome sequencing resulted in identification of 76 differentially expressed genes (DEGs) associated with hepatotoxicity between the TP and TP + CR groups. Of these, Three DEGs (Cyp1a2,Gsta4, and Gstp1) were validated using quantitative real-time PCR analysis. In conclusion, CR protected CIA mice from TP-induced toxicity through modulation of the cytochrome P450 and glutathione metabolism pathways.

15.
Molecules ; 27(12)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35744811

RESUMO

Triptolide (TP) is a potential drug candidate for the treatment of cancer, but its use was hampered by its systemic toxicity and poor water solubility. Hence, a TP-CSO prodrug was synthesized by conjugating TP to chitosan oligosaccharide (CSO), and characterized by 1H NMR, FTIR, DSC and XRD analyses. The TP-CSO containing about 4 wt% of TP exhibited excellent water solubility (15 mg/mL) compared to TP (0.017 mg/mL). Compared with TP, the pharmacokinetics of the conjugate after oral administration showed a three-fold increase in the half-life in the blood circulation and a 3.2-fold increase in AUC (0-∞). The orally administered TP-CSO could more effectively inhibit tumor progression but with much lower systemic toxicity compared with TP, indicating significant potential for further clinical trials. In conclusion, CSO-based conjugate systems may be useful as a platform for the oral delivery of other sparingly soluble drugs.


Assuntos
Quitosana , Diterpenos , Neoplasias Pancreáticas , Fenantrenos , Pró-Fármacos , Quitosana/química , Diterpenos/química , Compostos de Epóxi/química , Compostos de Epóxi/uso terapêutico , Humanos , Fenantrenos/química , Fenantrenos/uso terapêutico , Pró-Fármacos/uso terapêutico , Água , Neoplasias Pancreáticas
16.
Drug Deliv ; 29(1): 89-98, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34964425

RESUMO

Celastrol is a promising antitumor drug candidate, but the poor water solubility and cytotoxicity limit its clinical application. Herein, we synthesized a Celastrol (Cel)-chitosan oligosaccharide (CSO) conjugate (Cel-CSO) for drug delivery. Celastrol was conjugated to a CSO backbone via amide bond formation, which was verified by infrared spectrum (IR) analyses. The Cel-CSO contained ∼10 wt% of Celastrol showed excellent aqueous solubility (18.6 mg/mL) in comparation with the parent Celastrol. Cel-CSO significantly inhibited tumor growth, induced apoptosis, and effectively suppressed tumor metastasis in human pancreatic cancer cells (BxPC-3). While the cytotoxicity of Cel-CSO in hepatic cells (HL7702) was lower than that of the free Celastrol. Cel-CSO enhanced the anticancer efficacy, promoted the circulation time of Celastrol, and reduced the subacute toxicity, which indicated that CSO can be a promising Celastrol delivery system for pancreatic cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Quitosana/química , Neoplasias Pancreáticas/patologia , Triterpenos Pentacíclicos/farmacologia , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Liberação Controlada de Fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Oligossacarídeos/química , Tamanho da Partícula , Triterpenos Pentacíclicos/administração & dosagem , Solubilidade , Carga Tumoral/efeitos dos fármacos
17.
Anal Chim Acta ; 1176: 338769, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34399896

RESUMO

A novel magnetic borate-modified MXene composite was prepared by in situ growth of Fe3O4 particles onto the surface of phenylboronic acid modified Ti3C2Tx nanosheets. The magnetic composite possesses highly selective recognition properties to catecholamines, and high adsorption capacity (up to 319.6 µmol g-1) for dopamine. Besides, the adsorption of urinary catecholamines can be accomplished within 2.0 min. The excellent adsorption performance can be assigned to its unique 2D layered structures, which helps to shorten the diffusion path and facilitate molecular transport. In addition, the multilayer adsorption and the synergetic interactions of borate affinity, van der Waals forces, hydrogen bonding and π-π stacking also contribute to the adsorption. By coupling the magnetic boronate affinity composites with high-performance liquid chromatography-fluorescence detection, a sensitive method for the determination of catecholamines in urine samples was proposed. The validation results revealed it can offer good linearities (correlation coefficients higher than 99%). The method detection limits were 0.06, 0.16, 0.03 and 0.14 ng mL-1 for norepinephrine, epinephrine, dopamine and isoprenaline, respectively, and relative recoveries for these catecholamines were in the range of 98.56-108.1%, 92.56-110.0%, 98.79-112.3% and 88.14-97.81%, respectively. The proposed method was successfully applied to analyze the catecholamines in the urine samples from 15 healthy volunteers and 16 patients with Alzheimer's disease. The results indicated that the magnetic borate-modified Mxene composite possesses superior extraction performance, and can be used as an outstanding candidate for the extraction of catecholamines in pre-clinical or clinical studies.


Assuntos
Boratos , Catecolaminas , Adsorção , Cromatografia Líquida de Alta Pressão , Humanos , Fenômenos Magnéticos , Magnetismo , Extração em Fase Sólida
18.
J Sep Sci ; 44(18): 3398-3406, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34265181

RESUMO

In this study, a new Ti3 C2 Tx -coated fiber was synthesized and utilized as coatings for solid-phase microextraction of seven polychlorinated biphenyls. The as-produced multilayered Ti3 C2 Tx MXene was characterized by X-ray diffractometer, thermos-gravimetric analysis, scanning electron microscopy, and energy dispersive spectroscopy. It is noteworthy that the Ti3 C2 Tx showed some attractive features including unique 2D layered structures, large surface area, good hydrophilicity, and rich active recognition sites, endowing it has a high affinity towards the target polychlorinated biphenyls. Subsequently, the affecting parameters on the extraction efficiency of polychlorinated biphenyls were optimized. Under the optimal conditions, a novel method for the analysis of polychlorinated biphenyls in water samples was proposed. The Ti3 C2 Tx -coated fiber-based solid-phase microextraction method showed good linearity (r2  > 0.9928), high enrichment factors (268-442), low limits of detection (0.06-0.15 ng/L), and satisfactory repeatability (RSDs < 7.5%) for the polychlorinated biphenyls. The excellent method recoveries were in the range of 90.0-98.4, 92.0-98.2, and 92.0-98.0% for river water, lake water, and tap water samples, respectively. These results suggested that the proposed Ti3 C2 Tx -coated fiber-based method represents a promising alternative for the analysis of polychlorinated biphenyls.

19.
Food Chem ; 339: 128079, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152872

RESUMO

In this work, an efficient method for the determination of ß-agonists and fluoroquinolones was established, based on a mixed-mode sorbent of magnetic sulfonated covalent organic framework composites. By coupling with HPLC-MS/MS, the main factors that affect the extraction procedure were optimized. Under the optimal conditions, the proposed HPLC-MS/MS method was successfully utilized for the extraction of ß-agonists and fluoroquinolones in milk and pork meat samples. The method showed good linearities (R2 ≥ 0.9916), and low LOQs of 0.1-0.2 ng g-1 for ß-agonists and fluoroquinolones. The adsorption mechanism was investigated with the assistance of quantum chemistry calculation method, and it is worth noting that the sorbent relied mainly on the multiple adsorption mechanisms, including π-π stacking, hydrophobic, electrostatic attraction and hydrogen-bonding interactions. This work not only provides a simple method for the preparation of a mixed-mode sorbent, but also a routine analysis strategy for monitoring the illegal use of ß-agonists and fluoroquinolones.


Assuntos
Agonistas Adrenérgicos beta/análise , Fluoroquinolonas/análise , Análise de Alimentos/métodos , Imãs/química , Estruturas Metalorgânicas/síntese química , Extração em Fase Sólida/métodos , Ácidos Sulfônicos/química , Agonistas Adrenérgicos beta/química , Agonistas Adrenérgicos beta/isolamento & purificação , Adsorção , Animais , Técnicas de Química Sintética , Fluoroquinolonas/química , Fluoroquinolonas/isolamento & purificação , Contaminação de Alimentos/análise , Carne/análise , Estruturas Metalorgânicas/química , Leite/química , Suínos , Fatores de Tempo
20.
Fitoterapia ; 147: 104730, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32971205

RESUMO

One new bisesquiterpenoid, biepiasreorlid II (1), three new sesquiterpene lactones 8α-methoxy-epiasterolid (4), 3ß-acetoxyl-8-epiasterolid (5), and 3ß-acetoxyl-atractylenolide I (6), along with five known analogues (2-3 and 7-9), were obtained from rhizome of Atractylodes macrocephala Koidz. All structures were assigned on the basis of detailed spectroscopic analyses. The absolute configuration of 1 was established by the analysis of single-crystal X-ray diffraction with Ga Kα radiation, and 4-6 were elucidated by TDDFT-ECD calculations. The CREB agonistic activity was investigated in HEK293T cells using dual luciferase reporter assay. Compounds 1, 2, 5, and 7-9 exhibited strong to agonistic activities on CREB.


Assuntos
Atractylodes/química , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/antagonistas & inibidores , Lactonas/farmacologia , Sesquiterpenos/farmacologia , China , Células HEK293 , Humanos , Lactonas/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Rizoma/química , Sesquiterpenos/isolamento & purificação
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