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1.
Phytochem Anal ; 33(8): 1246-1256, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36191586

RESUMO

INTRODUCTION: Anthraquinones are considered to be an important class of bioactive substances in Cassiae semen, and the content of anthraquinones is an essential indicator of the quality of Cassiae semen raw herbal materials. OBJECTIVES: The present study aimed to propose a novel, efficient and effective ultra-high-performance liquid chromatography (UHPLC) method for the simultaneous determination of aurantio-obtusin, aloe-emodin, rhein, obtusin, emodin, chrysophanol and physcion, with the help of natural deep eutectic solvents (NADESs) as extraction solvents. METHODOLOGY: NADESs were introduced to the simultaneous extraction of anthraquinones from Cassiae semen samples. Several NADESs were designed by menthol, choline chloride, d-glucose as hydrogen bond acceptors, with nine different acids and appropriate water as hydrogen bond donors. The parameters affecting the extraction efficiency of seven anthraquinones were demonstrated in detail. RESULTS: Among the obtained NADESs, the highest extraction efficiency was demonstrated by a solution consisting of d-glucose, lactic acid and water with a molar ratio of 1:5:4. The seven anthraquinones were separated on an ACQUITY UPLC® BEH C18 column (2.1 mm × 100 mm, 1.8 µm) and detected within 12 min by a photodiode array (PDA) detector at 254 and 284 nm. The limits of detection and quantitation were from 1.00 to 7.26 µg/l and 3.29 to 24.22 µg/l, respectively. And Cassiae semen sample-based recoveries ranged from 81.13% to 113.78% with the relative standard deviation (RSD) (n = 6) of 1.4% to 10.1%. CONCLUSION: The developed method demonstrated that NADESs were applied successfully to analyse the anthraquinones in Cassiae semen samples collected from different regions in China.


Assuntos
Cassia , Emodina , Cassia/química , Solventes Eutéticos Profundos , Antraquinonas , Cromatografia Líquida de Alta Pressão/métodos , Glucose , Água , Sementes/química
2.
J Sci Food Agric ; 100(13): 4840-4848, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32483821

RESUMO

BACKGROUND: Aflatoxins, a kind of carcinogen, have attracted increasing attention due to their toxicity and harmfulness to human health. Traditional methods for aflatoxins analysis usually involve tedious extraction steps with a subsequent derivatization process. Herein, a simple and efficient liquid-phase microextraction method based on deep eutectic solvents (DESs) for direct analysis of aflatoxins was developed. RESULTS: Adopting DESs as the extractant, we surprisingly found out that DESs could either achieve good extraction performance or play a similar role to the derivatization agent, achieving an enhancement of fluorescence intensity for direct analysis of aflatoxins by high-performance liquid chromatography combined with fluorescent detection. Under optimal conditions obtained by response surface methodology, the method provided satisfactory linear ranges (0.01-0.75 µg kg-1 for AFB1 and AFG1, 0.003-0.25 µg kg-1 for AFB2 and AFG2) with good determination coefficients (R2 > 0.9988), a low detection limit (0.0005-0.003 µg kg-1 ), and good recovery rates (72.05-113.54%). CONCLUSION: These results highlighted superiorities of the one-step DES strategy for analysis of aflatoxins in edible oils, providing insights for future development of efficient methods in food analysis. © 2020 Society of Chemical Industry.


Assuntos
Aflatoxinas/análise , Aflatoxinas/isolamento & purificação , Microextração em Fase Líquida/métodos , Óleos de Plantas/química , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Solventes/química
3.
J Environ Sci Health B ; 55(3): 250-256, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31694450

RESUMO

Paclobutrazol (PBZ) is a plant growth regulator (PGR) widely used in fruit and vegetable cultivation. However, due to the severe toxicity of PBZ, a sub-ppm level maximum residue limit (MRL) was established worldwide. Therefore, it is significant to propose a rapid, sensitive and high throughput screening method for monitoring the PBZ residues in foods. In this study, a simple and sensitive indirect competitive Enzyme-linked immunosorbent assay (icELISA) was established for PBZ detection in fruits basing polyclonal antibody. For both economy and pollution prevention, a microwave-solvent-free method was used to synthesize the PBZ hapten with high efficiency. The detection conditions, such as coating antigen concentration, antibody concentration, organic reagent concentration, ionic strength and pH, were optimized. Under the optimized conditions, this method showed high sensitivity and specificity. The detection range is 1.27-138.23 ng/mL, half-maximum inhibition concentration (IC50) is 13.26 ng/mL, and the IC20 was lower than the reported ELISAs for PBZ. Additionally, this method had high accuracy and precision. The recoveries were ranged from 88.78% to 96.80% in PBZ spiked apple samples with RSD below 4%. All the results showed that the polyclonal antibody based icELISA could be useful for PBZ screening in fruit samples.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Contaminação de Alimentos/análise , Triazóis/análise , Triazóis/imunologia , Animais , Anticorpos/imunologia , Reações Cruzadas , Feminino , Análise de Alimentos/métodos , Frutas , Haptenos/imunologia , Limite de Detecção , Malus/química , Camundongos Endogâmicos BALB C , Sensibilidade e Especificidade
4.
J Sep Sci ; 41(18): 3561-3568, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30055075

RESUMO

Monodisperse silica spheres that comprised a rhombic-dodecahedral zeolitic imidazolate framework core-shell microsphere were applied in the sample pretreatment of navel orange. A rapid and efficient liquid chromatography with triple quadrupole tandem mass spectrometry method was established for simultaneously quantifying four plant growth regulators, 6-benzylaminopurin, indole-3-acetic acid, indolepropionic acid, 3-indolebutyric acid, in navel oranges. A satisfactory result was obtained, i.e., the peak area of the four plant growth regulators against concentration was linear with good correlation coefficients of 0.99987-0.99991. Under optimized conditions, the limits of detection were 3.0-59.4 µg/L for the four plant growth regulators. This method was applied to the simultaneous analysis of the four plant growth regulators in commercial samples, and all the detections were confirmed by acquiring transitions for each pesticide in the samples.


Assuntos
Citrus sinensis/química , Imidazóis/química , Reguladores de Crescimento de Plantas/isolamento & purificação , Dióxido de Silício/química , Zeolitas/química , Adsorção , Compostos de Benzil/química , Compostos de Benzil/isolamento & purificação , Cromatografia Líquida , Ácidos Indolacéticos/química , Ácidos Indolacéticos/isolamento & purificação , Indóis/química , Indóis/isolamento & purificação , Microesferas , Tamanho da Partícula , Reguladores de Crescimento de Plantas/química , Purinas/química , Purinas/isolamento & purificação , Espectrometria de Massas em Tandem
5.
Phytochem Anal ; 29(6): 639-648, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30033674

RESUMO

INTRODUCTION: Camellia oleifera flowers are rich in flavonoids, but there has been little attention on their application. A simple and reliable method for determining the content of flavonoids in C. oleifera flowers would be very helpful for the utilisation of agriculture resources. OBJECTIVE: To develop an efficient analytical method for the determination of flavonoids in C. oleifera flowers by high-performance liquid chromatography-ultraviolet (HPLC-UV) detection. METHODOLOGY: Preparing an environmentally-friendly and effective solvent - deep eutectic solvents (DESs) - for compound extraction. Then investigating the influential factors of ultrasound-assisted extraction with DESs by the Box-Behnken design combined with response surface methodology. RESULTS: DES-5 synthesised with choline chloride and lactic acid (1:2) acquired excellent extractability for four flavonoids (quercetin 3-O-rhamnoside, kaempferol 3-O-rhamnoside and their aglycones) with different polarity. The proposed method, which could simultaneously determine four flavonoids with HPLC-UV detection for the first time, displays satisfactory recovery yields and high precision with inter-day relative standard deviation lower than 5.80%. CONCLUSION: DESs could be promising solvents for efficiently and selectively extracting bioactive compounds from plant materials, and the analytical method for flavonoids of C. oleifera flowers could provide reference value for its application and be used in other plant resources.


Assuntos
Camellia/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flores/química , Solventes/química
6.
J Asian Nat Prod Res ; 20(4): 299-305, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28569087

RESUMO

Three new mexicanolide-type limonoids, 3-O-propionylproceranolide (1), 6-O-acetylswietenin B (2), and 6-deoxyswietemahonin A (3), together with 15 known limonoids, were isolated from the seeds of Swietenia macrophylla (Meliaceae). The structures of those new compounds were established by extensive analysis of MS, 1D, and 2D NMR spectral data.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Limoninas/isolamento & purificação , Meliaceae/química , Medicamentos de Ervas Chinesas/química , Limoninas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sementes/química
7.
J Sep Sci ; 40(10): 2117-2122, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28346746

RESUMO

A simple and reliable method was established for simultaneous determination of 4-hydroxyphenyl acetic acid, 4-hydroxyphenyl lactic acid, and 3,4-hydroxyphenyl propionic acid in human urine by high-performance liquid chromatography with fluorescence detection. Solid-phase extraction was used to eliminate the interferences in urine. The separation of three analytes was achieved using a C18 column and a mobile phase formed by a 95:5 v/v mixture of 50 mmol/L ammonium acetate buffer at pH 6.8 that contained 5 mmol/L tetrabutyl ammonium bromide and acetonitrile. Under the optimized conditions, the detection limits of 4-hydroxyphenyl acetic acid, 4-hydroxyphenyl lactic acid, and 3,4-hydroxyphenyl propionic acid were 4.8 × 10-3 , 8.80 × 10-3 , and 9.00 × 10-3 mg/L, respectively, and the recoveries were in the range of 85.0-120.0% with relative standard deviations of 1.5-3.1%. This method was used to analyze urine samples from breast cancer patients, healthy people and post-surgery breast cancer patients. Significant differences in urinary levels of 4-hydroxyphenyl acetic acid and 4-hydroxyphenyl lactic acid could be found between the breast cancer patients group and other two groups. No effect of age and sex was observed on the urinary levels of 4-hydroxyphenyl acetic acid and 4-hydroxyphenyl lactic acid. This method might be helpful for cancer biomarkers discovery in urine.


Assuntos
Acetatos/urina , Ácido Láctico/urina , Propionatos/urina , Neoplasias da Mama/urina , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Limite de Detecção , Masculino , Extração em Fase Sólida
8.
Macromol Rapid Commun ; 37(21): 1754-1759, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27717060

RESUMO

The development of effective strategies for fabrication of fluorescent organic nanoparticles (FONs) with an aggregation-induced emission (AIE) feature has an important impact on the biomedical applications of these AIE-active FONs. In the current work, an ultrafast strategy for fabricating AIE-active FONs is developed through a "one-pot" microwave-assisted, catalysts-free, and solvent-free Kabachnik-Fields (KF) reaction for the first time. It is demonstrated that such organophosphorous-containing AIE-active block polymers can be synthesized within 2 min under air atmosphere through the microwave-assisted KF reaction. These polymers show amphiphilic properties and can self-assemble into mPEG-CHO-Phe-NH2 -DEP FONs, which display high water dispersibility and desirable optical properties. Biological evaluation results suggest that the mPEG-CHO-Phe-NH2 -DEP FONs exhibit low toxicity and are potential for biological imaging applications. More importantly, many other multifunctional AIE-active FONs can also be fabricated through the strategy described in this work owing to the universality of KF reaction. Besides, combined with the excellent properties of mPEG-CHO-Phe-NH2 -DEP FONs, it is believed that such microwave-assisted KF reaction shall be an effective route for designing various AIE-active nanomaterials for different biomedical applications.


Assuntos
Corantes Fluorescentes/síntese química , Micro-Ondas , Nanopartículas/química , Compostos Organofosforados/síntese química , Corantes Fluorescentes/química , Compostos Organofosforados/química , Tamanho da Partícula , Propriedades de Superfície , Fatores de Tempo
9.
Macromol Rapid Commun ; 37(20): 1657-1661, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27547886

RESUMO

Driven by the high demand for sensitive and specific tools for optical imaging, fluorescent nanoprobes with various working mechanisms and advanced functionalities are flourishing at an incredible speed. This work reports the design and fabrication of aggregation-induced emission (AIE)-active fluorescent organic nanoparticles (FNPs) via forming dynamic phenyl borate between diol containing hydrophobic AIE dye (APD-PhCHO) and phenylboronic acid pendant hydrophilic polymers (PEGMA-VPBA) within 30 min. The final AIE-active APD-PhCHO-PEGMA-VPBA FNPs display high water dispersibility and strong fluorescence emission because of their amphiphilic properties and AIE feature. Biological evaluation suggests that APD-PhCHO-PEGMA-VPBA FNPs possess negative effect on HeLa cells and desirable optical properties for biological imaging. More importantly, phenyl borate is a dynamic bond with pH and glucose responsiveness. Furthermore, different functions can be designed and introduced into these AIE-active systems through adoption of different monomers for good applicability of free radical polymerization. Therefore, this work provides a novel platform for preparation of multifunctional AIE-active nanosystems with responsiveness for various biomedical applications.


Assuntos
Corantes Fluorescentes/química , Imagem Molecular , Nanopartículas/química , Polietilenoglicóis/química , Tensoativos/química , Sobrevivência Celular , Fluorescência , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Tamanho da Partícula , Polietilenoglicóis/síntese química , Propriedades de Superfície , Tensoativos/síntese química
10.
J Sep Sci ; 39(12): 2380-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27138689

RESUMO

Most organotin compounds that have been widely used in food packaging materials and production process show serious toxicity effects to human health. In this study, a simple and low-cost method based on high-performance liquid chromatography with inductively coupled plasma mass spectrometry for the simultaneous determination of four organotins in edible vegetable oil samples was developed. Four organotins including dibutyltin dichloride, tributyltin chloride, diphenyltin dichloride, and triphenyltin chloride were simultaneously extracted with methanol using the low-temperature precipitation process. After being concentrated, the extracts were purified by matrix solid-phase dispersion using graphitized carbon black. The experimental parameters such as extraction solvent and clean-up material were optimized. To evaluate the accuracy of the new method, the recoveries were investigated. In addition, a liquid chromatography with tandem mass spectrometry method was also proposed for comparison. The procedures of extracting and purifying samples for the analysis were simple and easy to perform batch operations, also showed good efficiency with lower relative standard deviation. The limits of detection of the four organotins were 0.28-0.59 µg/L, and the limits of quantification of the four organotins were 0.93-1.8 µg/L, respectively. The proposed method was successfully applied to the simultaneous analysis of the four organotins in edible vegetable oil. Some analytes were detected at the level of 2.5-28.8 µg/kg.


Assuntos
Compostos Orgânicos de Estanho/análise , Óleos de Plantas/química , Temperatura , Cromatografia Líquida , Espectrometria de Massas em Tandem
11.
J Sep Sci ; 37(11): 1352-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24659386

RESUMO

A new method for the determination of six plant growth regulators, 3-indolylacetic acid, 3-indolepropionic acid, 2-naphthoxyacetic acid, 2,4-dicholrophenoxyacetic acid, 1-naphthlcetic acid, and methyl naphthalene-1-acetate, in pears was established by liquid chromatography with electrospray ionization mass spectrometry. In this study, a microwave-assisted extraction technique was first applied for the determination of plant growth regulators in fruit and three cleanup techniques were, respectively, investigated for the purification of pear samples. The chromatographic separation was performed on a Diamonsil C18 column by using 0.01 mol/L formic acid/ammonium formate buffer solution (pH 3.5)/methanol (35:65, v/v) as the mobile phase with a flow rate of 0.7 mL/min in 1:1 split mode. The LODs ranged from 0.3 to 1.9 µg/kg. Under optimized conditions, the average recoveries (five replicates) for six plant growth regulators (spiked at 0.01, 0.05, and 0.5 mg/kg) ranged from 78.9 to 118.0%, and the RSDs were 1.4-10.3%.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Reguladores de Crescimento de Plantas/análise , Pyrus/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Contaminação de Alimentos , Frutas/química , Micro-Ondas , Reguladores de Crescimento de Plantas/isolamento & purificação
12.
Acta Chim Slov ; 61(1): 73-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24664329

RESUMO

Sensitive and selective fluorescent probe of thiols with lower limit of detection based on fluorescence resonance energy transfer (FRET) between fluorescein and Au nanoparticles (AuNPs) is presented. The fluorescein-AuNPs complex emits weak fluorescence. Upon chemically binding to organosulfur compound that contains a carbon-bonded sulfhydryl (-C-SH or R-SH) thiols, a stable enhancement of fluorescence is observed due to the competitive binding on AuNPs between thiols and fluorescein. The magnitude of fluorescence enhancement is linearly proportional to the logarithm of the thiols concentration. We use cysteine as an example to show how this useful analytical assay works selectively, which is closely nonresponsive to 20 other amino acids even though they are in solution at a concentration 10 times greater than the thiols. The detection limit for cysteine is 7.27 × 10-9 mol L-1. The possible mechanism of this assay is discussed in details. The proposed method was successfully applied for the determination of Cys in urine.


Assuntos
Fluoresceína/química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Ouro/química , Nanopartículas Metálicas/química , Compostos de Sulfidrila/química , Adulto , Cisteína/química , Cisteína/urina , Feminino , Humanos
13.
Food Chem ; 444: 138666, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38341916

RESUMO

This work presents an efficient sorbent for plant growth regulators (PGRs) by regulating the defects of a metal-organic framework MIL-101(Cr). Using the regulated MIL-101(Cr), we developed a simple and effective method for the simultaneous determination of eleven PGRs in fresh fruit juice. The extraction conditions were optimized by an orthogonal array design. Under optimal conditions, the method showed a satisfactory limit of detection (0.1-1.2 ng/g), recovery rates (83.4-110.2 %), and precision (2.9-18.0 % for intra-day and 2.7-10.8 % for inter-day), as well as a greatly suppressed matrix effect. Notably, regulating the defects significantly enhanced the desorption of PGRs on MIL-101(Cr). The sorbent didn't need to be destroyed to release the adsorbed PGRs and could be reused at least 6 times. Furthermore, the defects of MIL-101(Cr) and interactions between the sorbent and PGRs were studied by TGA, ATR-IR, XPS, NH3-TPD and UV-Vis DRS.


Assuntos
Estruturas Metalorgânicas , Reguladores de Crescimento de Plantas/análise , Sucos de Frutas e Vegetais , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida/métodos
14.
Adv Sci (Weinh) ; : e2402465, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728587

RESUMO

Aggressive nature of colon cancer and current imprecise therapeutic scenarios simulate the development of precise and effective treatment strategies. To achieve this, a tumor environment-activated photosensitized biomimetic nanoplatform (PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM) is fabricated by encapsulating metal-organic framework loaded with developed photosensitizer PEG2000-SiNcTI-Ph and immunoadjuvant CpG oligodeoxynucleotide within fusion cell membrane expressing programmed death protein 1 (PD-1) and cluster of differentiation 47 (CD47). By stumbling across, systematic evaluation, and deciphering with quantum chemical calculations, a unique attribute of tumor environment (low pH plus high concentrations of adenosine 5'-triphosphate (ATP))-activated photodynamic effect sensitized by long-wavelength photons is validated for PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM, advancing the precision of cancer therapy. Moreover, PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM evades immune surveillance to target CT26 colon tumors in mice mediated by CD47/signal regulatory proteins α (SIRPα) interaction and PD-1/programmed death ligand 1 (PD-L1) interaction, respectively. Tumor environment-activated photodynamic therapy realized by PEG2000-SiNcTI-Ph/CpG-ZIF-8@CM induces immunogenic cell death (ICD) to elicit anti-tumor immune response, which is empowered by enhanced dendritic cells (DC) uptake of CpG and PD-L1 blockade contributed by the nanoplatform. The photodynamic immunotherapy efficiently combats primary and distant CT26 tumors, and additionally generates immune memory to inhibit tumor recurrence and metastasis. The nanoplatform developed here provides insights for the development of precise cancer therapeutic strategies.

15.
Foods ; 12(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36832868

RESUMO

A new method for simultaneous determination of puerarin, daidzin, daidzein and genistein in Radix puerariae by ultra-high performance liquid chromatography was established. The target analytes were extracted from Radix puerariae by 70% ethylene glycol with the assistance of ultrasonication, purified by the absorption of N-propyl ethylenediamine (PSA), and separated on a Supersil ODS column (4.6 mm × 250 mm × 2.5 µm). Gradient elution in 12 min was performed with the mobile phase 0.1% formic acid(A)-acetonitrile(B). The column temperature was 25 °C and the flow rate was 1 mL/min. The detection wavelength of the four target analytes was 250 nm. The limits of detection (LODs) of puerarin, daidzin, daidzein and genistein were 0.086 mg/L, 0.020 mg/L, 0.027 mg/L and 0.037 mg/L, respectively, and limits of quantitation (LOQs) were 0.29 mg/L, 0.065 mg/L, 0.090 mg/L and 0.12 mg/L, respectively. The recovery of the four substances ranged from 90.5% to 109.6%, and the relative standard deviation (n = 6) was less than 7.7%. With the established methods, puerarin, daidzin, daidzein and genistein in Radix puerariae from 11 origins were determined. The contents of the four compounds varied with the origin and variety. It provides basic data and technical means for quality control and regulation of Radix puerariae.

16.
Foods ; 12(9)2023 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-37174447

RESUMO

In this study, Anoectochilus formosanus polysaccharide (AFP) was acquired a via water extraction and alcohol precipitation method. The immunoregulatory activity of AFP was first evaluated on cyclophosphamide (Cy)-treated mice. Galacturonic acid, glucose and galactose were confirmed to be the main components of AFP. AFP demonstrated the ability to stimulate the production of TNF-α and IL-6 in RAW 264.7 macrophages. Not surprisingly, the activation of the NF-κB signaling pathway by AFP was validated via Western blot analysis. Furthermore, AFP could alleviate Cy-induced immunosuppression, and significantly enhance the immunity of mice via increasing the thymus index and body weight, stimulating the production of cytokines (IgA, IgG, SIgA, IL-2, IL-6 and IFN-γ). The improvement in the intestinal morphology of immunosuppressed mice showed that AFP could alleviate Cy-induced immune toxicity. These results have raised the possibility that AFP may act as a natural immunomodulator. Overall, the study of AFP was innovative and of great significance for AFP's further application and utilization.

17.
Food Chem ; 407: 135074, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36493489

RESUMO

In view of the molecular structure of Aristolochic acid I (AA-I) and Aristolochic acid II (AA-II), MIL-101(Fe) was selected as the sorbent to develop a dispersive solid-phase extraction (d-SPE) method for capturing the two analytes from Houttuynia cordata. The interactions between the sorbent and analytes were investigated by FT-IR, XPS and UV-Vis DRS spectra. The optimized method demonstrated good linearity with R2 > 0.9999. The limit of detections (LODs) were 0.007 mg/L and 0.014 mg/L for AA-I and AA-II, respectively, lower than the limit stipulated by Chinese Pharmacopoeia (0.001 %, w/w). The recoveries for AA-I and AA-II were within the range of 73.3-106.4 %. The precisions of intra-day and inter-day were 0.9-5.8 % and 2.1-5.8 %, respectively. Thus, the established method demonstrated to be efficient and reliable to determine AA-I and AA-II in Houttuynia cordata.


Assuntos
Ácidos Aristolóquicos , Houttuynia , Espectroscopia de Infravermelho com Transformada de Fourier , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos
18.
Adv Healthc Mater ; 12(29): e2301450, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37537878

RESUMO

Ulcerative colitis (UC), a refractory disease, has become a global problem. Herein, a biomimetic nanoplatform (AU-LIP-CM) comprising Au cluster enzymes (AU)-loaded liposomes (AU-LIP) camouflaged with the fusion membrane (CM) consisting of neutrophil (NC) and red blood cell (RBC) membrane is designed for the treatment of UC. Briefly, revealed by second near-infrared (NIR-II) imaging through collection of fluorescence emitting >1200 nm from AU, the improved inflammatory targeting behavior contributed by CM cloaking, which inherits abilities of inflammatory targeting and immune escape from NC and RBC, respectively, promotes specific accumulation of AU within inflammatory intestines with up to ≈11.5 times higher than that of bare AU. Afterward, AU possessing superoxide dismutase- and catalase-like activities realizes high-efficiency scavenging of reactive oxygen species (ROS), leading to repair of intestinal barriers, regulation of the immune system, and modulation of gut microbiota, which surpass first-line UC drug. In addition, study of underlying therapeutic mechanism demonstrated that the treatment with AU-LIP-CM can alter the gene signature associated with response to ROS for UC mice to a profile similar to that of healthy mice, deciphering related signal pathways. The strategy developed here provides insights of learning from properties of natural bio-substances to empower biomimetic nanoplatform to confront diseases.


Assuntos
Colite Ulcerativa , Camundongos , Animais , Colite Ulcerativa/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Biomimética , Intestinos , Membrana Eritrocítica , Modelos Animais de Doenças
19.
ACS Nano ; 17(15): 14775-14791, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37477584

RESUMO

Oral administration of probiotics is a promising method to alleviate inflammatory bowel diseases (IBDs). However, gastrointestinal environmental sensitivity and inferior intestinal colonization of probiotics hinder the alleviation effect. Here, we developed a simple yet effective modified prebiotic-based "shield" (Fe-TA@mGN) composed of an Fe3+-tannic acid cross-linking network and carboxymethylated ß-glucan for arming Escherichia coli Nissle 1917 (EcN@Fe-TA@mGN). The Fe-TA@mGN "shield" not only acted as a dynamic barrier to enhance the gastrointestinal stress resistance ability of EcN but also aided the intestinal colonization of EcN as well as synergized with EcN for the alleviation of dextran sulfate sodium (DSS) induced colitis. More specifically, with the protection of the Fe-TA@mGN "shield", the survival rate of armed EcN could be up to ∼1720 times higher than that of bare EcN after exposure to simulated gastric fluid. Excitingly, the intestinal retention rate of EcN@Fe-TA@mGN was as high as 47.54 ± 6.06% at 16 h post-administration, while almost all bare EcNs were excreted out at 8 h post-administration. With all of the aforementioned attributes, EcN@Fe-TA@mGN efficiently alleviated colitis, verified by the repair of the intestinal barrier and the attenuation of inflammation. Moreover, for EcN@Fe-TA@mGN, mGN synergized with EcN to positively modulate gut microbiota and promote the production of short-chain fatty acids (SCFAs, especially for butyric acid, a primary source for maintaining intestinal health), both of which would further advance the alleviation of colitis. We envision that the strategy developed here will inspire the exploitation of various prebiotics to arm probiotics for the effective alleviation of IBD.


Assuntos
Colite , Probióticos , Humanos , Colite/induzido quimicamente , Colite/tratamento farmacológico , Intestinos , Prebióticos , Probióticos/farmacologia , Probióticos/uso terapêutico
20.
Foods ; 11(14)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35885257

RESUMO

A new rapid and accurate method was developed for simultaneous determination of pyridoxine and pyridoxal in ginkgo seeds, using ultra-performance liquid chromatography (UPLC) equipped with a fluorescence detector. Diluted hydrochloric acid solution was used as the extracting solvent. For the pretreatment of extracts, a zeolitic imidazolate framework material (ZIF-8) was prepared and characterized. An ODS-BP column (4.6 mm × 250 mm × 5 µm) was used for separation. The conditions of sample extraction, cleaning and separation were optimized. The linear correlation coefficient (R2) of the analyte was better than 0.9999, indicating good linearity. The limits of detection (LODs) of pyridoxal and pyridoxine were 0.0065 mg/kg and 0.0057 mg/kg, respectively, and limits of quantitation (LOQs) were 0.022 mg/kg and 0.019 mg/kg, respectively. The recovery of the two substances ranged from 86.2% to 110.4%, and the relative standard deviation (n = 6) was less than 7.5%. The method was applied to determine the contents of pyridoxine and pyridoxal in actual ginkgo seed samples with satisfactory results.

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