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1.
Adv Sci (Weinh) ; 8(17): e2100386, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34247445

RESUMO

Broadband near-infrared (NIR) photothermal and photoacoustic agents covering from the first NIR (NIR-I) to the second NIR (NIR-II) biowindow are of great significance for imaging and therapy of cancers. In this work, ultrathin two-dimensional plasmonic PtAg nanosheets are discovered with strong broadband light absorption from NIR-I to NIR-II biowindow, which exhibit outstanding photothermal and photoacoustic effects under both 785 and 1064 nm lasers. Photothermal conversion efficiencies (PCEs) of PtAg nanosheets reach 19.2% under 785 nm laser and 45.7% under 1064 nm laser. The PCE under 1064 nm laser is higher than those of most reported inorganic NIR-II photothermal nanoagents. After functionalization with folic acid modified thiol-poly(ethylene glycol) (SH-PEG-FA), PtAg nanosheets endowed with good biocompatibility and 4T1 tumor-targeted function give high performances for photoacoustic imaging (PAI) and photothermal therapy (PTT) in vivo under both 785 and 1064 nm lasers. The effective ablation of tumors in mice can be realized without side effects and tumor metastasis by PAI-guided PTT of PtAg nanosheets under 785 or 1064 nm laser. The results demonstrate that the prepared PtAg nanosheets with ultrathin thickness and small size can serve as a promising phototheranostic nanoplatform for PAI-guided PTT of tumors in both NIR-I and NIR-II biowindows.

2.
ACS Nano ; 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34269058

RESUMO

Spatially controlled preparation of heterostructures composed of layered materials is important in achieving interesting properties. Although vapor-phased deposition methods can prepare vertical and lateral heterostructures, liquid-phased methods, which can enable scalable production and further solution processes, have shown limited controllability. Herein, we demonstrate by using wet chemical methods that metallic Sn0.5Mo0.5S2 nanosheets can be deposited epitaxially on the edges of semiconducting SnS2 nanoplates to form SnS2/Sn0.5Mo0.5S2 lateral heterostructures or coated on both the edges and basal surfaces of SnS2 to give SnS2@Sn0.5Mo0.5S2 core@shell heterostructures. They also showed good light-to-heat conversion ability due to the metallic property of Sn0.5Mo0.5S2. In particular, the core@shell heterostructure showed a higher photothermal conversion efficiency than the lateral counterpart, largely due to its randomly oriented and polycrystalline Sn0.5Mo0.5S2 layers with larger interfacing area for multiple internal light scattering.

3.
Adv Drug Deliv Rev ; 176: 113839, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34153370

RESUMO

Cancer remains a leading health burden worldwide. One of the challenges hindering cancer therapy development is the substantial discrepancies between the existing cancer models and the tumor microenvironment (TME) of human patients. Constructing tumor organoids represents an emerging approach to recapitulate the pathophysiological features of the TME in vitro. Over the past decade, various approaches have been demonstrated to engineer tumor organoids as in vitro cancer models, such as incorporating multiple cellular populations, reconstructing biophysical and chemical traits, and even recapitulating structural features. In this review, we focus on engineering approaches for building tumor organoids, including biomaterial-based, microfabrication-assisted, and synthetic biology-facilitated strategies. Furthermore, we summarize the applications of engineered tumor organoids in basic cancer research, cancer drug discovery, and personalized medicine. We also discuss the challenges and future opportunities in using tumor organoids for broader applications.

4.
Environ Sci Pollut Res Int ; 28(44): 62306-62320, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34191263

RESUMO

Progesterone, an endocrine-disrupting chemical, has been frequently detected in wastewater for decades, posing a serious threat to ecological and human health. However, it is still a challenge to achieve the effective detection of progesterone in complex matrices water samples. In this study, a novel adsorbent CNT@CS/P(MAA) was prepared by grafting methacrylic polymers on the surface of modified carbon nanomaterials. Compared with other reported materials, the hybrid carbon nanomaterial could selectively identify the progesterone in the complex industrial pharmaceutical wastewater, and its adsorption performance is almost independent of the pH and environmental temperature. In addition, this nanomaterial could be reused with a good recovery rate. The prepared nanomaterials were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, nitrogen adsorption and desorption experiments, and thermogravimetric analysis. The results confirmed that the methacrylic polymers and chitosan layer were successfully grafted on the surface of carbon nanotubes. Adsorption isotherms, adsorption kinetics, and selectivity tests showed that CNT@CS/P(MAA) had a high adsorption capacity (44.45 mg·g-1), a fast adsorption rate and a satisfied selectivity for progesterone. Then, CNT@CS/P(MAA) was used as solid phase extraction sorbent and combined with HPLC to enrich progesterone from the wastewater samples. Under the optimum conditions, a good linearity was obtained with the correlation coefficient was 0.9998, and the limit of detection was 0.003 ng·mL-1. Therefore, this method could be used for the selective and effective detection of progesterone in industrial wastewater with complex substrates and provided a new method for the detection of progesterone in other environmental waters.


Assuntos
Nanotubos de Carbono , Preparações Farmacêuticas , Poluentes Químicos da Água , Adsorção , Humanos , Progesterona , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias , Poluentes Químicos da Água/análise
5.
J Chromatogr A ; 1647: 462155, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33957350

RESUMO

Aristolochic acid Ⅰ is a nephrotoxic compound and exist in some traditional Chinese medicines at trace level. Up to now, specific enrichment of aristolochic acid Ⅰ remains important procedure and key problem in its analysis. In this study, melamine was proposed as the recognition unit and grafted on the surface of metal-organic framework to fabricate a specific material for aristolochic acid Ⅰ. This material was prepared by using a two-step strategy and the preparation process was optimized. The physical and chemical properties were investigated using scanning electron microscopy, Fourier-transfer infrared spectroscopy, X-ray diffraction and nitrogen adsorption-desorption techniques. Adsorption properties were evaluated by binding experiments. The melamine modified material exhibited a uniform morphology, high specific surface area (460.20 m2 g-1), high adsorption capacity (25.57 mg g-1), fast mass transfer rate and excellent selectivity. Further, a specific and sensitive method was established by using this material as adsorbent of mini-solid phase extraction. The limit of detection was as low as 0.02 µg mL-1. Therefore, melamine modified metal-organic framework is an ideal adsorbent for the recognition and enrichment of aristolochic acid Ⅰ.


Assuntos
Ácidos Aristolóquicos , Estruturas Metalorgânicas/química , Extração em Fase Sólida/métodos , Triazinas/química , Ácidos Aristolóquicos/análise , Ácidos Aristolóquicos/química , Ácidos Aristolóquicos/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Limite de Detecção , Medicina Tradicional Chinesa
6.
J Chromatogr A ; 1638: 461889, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33485030

RESUMO

As a typical steroid hormone drug, estradiol (E2) is also one of the most frequently detected endocrine disrupting chemicals (EDCs) in the aquatic environment. Herein, in response to the potential risk of E2 in steroid hormone pharmaceutical industry wastewater to human and wildlife, a novel carbon nanotubes / amine-functionalized Fe3O4 (CNTs/MNPs@NH2) nanocomposites with magnetic responsive have been developed for the enrichment and extraction of E2 in pharmaceutical industry wastewater, where amino-functionalized Fe3O4 magnetic nanoparticles (MNPs@NH2) were used as a magnetic source. The resultant CNTs/MNPs@NH2 possessed both the features of CNTs and desired magnetic property, enabling to rapidly recognize and separate E2 from pharmaceutical industry wastewater. Meanwhile, the CNTs/MNPs@NH2 had good binding behavior toward E2 with fast binding kinetics and high adsorption capacity, as well as exhibited satisfactory selectivity to steroidal estrogen compounds. Furthermore, the change of pH value of aqueous phase in adsorption solvent hardly affected the adsorption of E2 by CNTs/MNPs@NH2, and the adsorption capacity of E2 ranged from 19.9 to 17.2 mg g-1 in the pH range of 3.0 to 11.0, which is a latent advantage of the follow-up development method to detect E2 in pharmaceutical industry wastewater. As a result, the CNTs/MNPs@NH2 serving as a solid phase extraction medium were successfully applied to efficiently extract E2 from pharmaceutical industry wastewater. Therefore, the CNTs/MNPs@NH2 nanocomposites could be used as a potential adsorbent for removing steroidal estrogens from water. More importantly, the developed method would provide a promising solution for the monitoring and analysis of EDCs in pharmaceutical industry wastewater.


Assuntos
Aminas/química , Indústria Farmacêutica , Estradiol/isolamento & purificação , Compostos Férricos/química , Nanocompostos/química , Nanotubos de Carbono/química , Águas Residuárias/química , Adsorção , Aerobiose , Anaerobiose , Estradiol/análise , Humanos , Cinética , Magnetismo , Nanocompostos/ultraestrutura , Reprodutibilidade dos Testes , Extração em Fase Sólida , Solventes/química , Temperatura , Águas Residuárias/análise
7.
Small ; 16(43): e2004173, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33006243

RESUMO

Transition metal dichalcogenide (TMD) nanomaterials, specially MoS2 , are proven to be appealing nanoagents for photothermal cancer therapies. However, the impact of the crystal phase of TMDs on their performance in photoacoustic imaging (PAI) and photothermal therapy (PTT) remains unclear. Herein, the preparation of ultrasmall single-layer MoS2 nanodots with different phases (1T and 2H phase) is reported to explore their phase-dependent performances as nanoagents for PAI guided PTT in the second near-infrared (NIR-II) window. Significantly, the 1T-MoS2 nanodots give a much higher extinction coefficient (25.6 L g-1  cm-1 ) at 1064 nm and subsequent photothermal power conversion efficiency (PCE: 43.3%) than that of the 2H-MoS2 nanodots (extinction coefficient: 5.3 L g-1  cm-1 , PCE: 21.3%). Moreover, the 1T-MoS2 nanodots also give strong PAI signals as compared to negligible signals of 2H-MoS2 nanodots in the NIR-II window. After modification with polyvinylpyrrolidone, the 1T-MoS2 nanodots can be used as a highly efficient agent for PAI guided PTT to effectively ablate cancer cells in vitro and tumors in vivo under 1064 nm laser irradiation. This work proves that the crystal phase plays a key role in determining the performance of nanoagents based on TMD nanomaterials for PAI guided PTT.


Assuntos
Técnicas Fotoacústicas , Fototerapia , Diagnóstico por Imagem , Molibdênio , Terapia Fototérmica
8.
ACS Appl Mater Interfaces ; 12(43): 48357-48362, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33052659

RESUMO

Since H5N1 virus is a highly infectious pathogen that causes outbreaks of avian influenza, developing a sensitive and rapid diagnostic platform to sense it becomes significant. Here, a novel label-free fluorescence sensing platform based on DNA-templated silver nanoclusters (DNA-Ag NCs) is developed to detect the H5N1 gene sequence representing H5N1 virus. The three-segment-branched DNA structure with closed cytosine-rich loop is designed as an effective template to produce fluorescent Ag NCs, which is different with the previous design of cytosine-rich loop formed by hairpin-like single-stranded DNA or double-stranded DNA. The proposed fluorescence detection approach gives a wide linear range (500 pM-2 µM) and a low detection limit (500 pM) to sense H5N1 gene sequence. Furthermore, selective analysis of target DNA shows that our constructed analytical strategy has a high selectivity to H5N1 gene sequence. It is regarded as a promising method for highly sensitive and selective sensing of H5N1 virus.


Assuntos
Técnicas Biossensoriais , DNA/química , Fluorescência , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Nanopartículas Metálicas/química , Prata/química , Animais , Bovinos , Tamanho da Partícula , Soroalbumina Bovina/química , Propriedades de Superfície
9.
Chem Commun (Camb) ; 56(71): 10285-10288, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32756720

RESUMO

Hierarchical superstructures of laterally or vertically oriented CoOOH nanoplates were prepared by topochemical conversion of CoAl-LDH microplates intercalated with CO32- or SO42- anions, respectively. The superstructure of vertically oriented nanoplates exhibited better electrocatalytic performance as compared to the lateral counterpart, attributable to the enlarged accessible surface area and promoted reaction kinetics.

10.
J Chromatogr A ; 1627: 461382, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823094

RESUMO

A method is described for the functionalization of magnetic carbon nanotubes to recognize aristolochic acid Ⅰ and Ⅱ. 3-Glycidyloxypropyltrimethoxysilane was used as a coupling agent to immobilize adenine on a solid support. The morphology and structure of adenine-coated magnetic carbon nanotubes was investigated using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and a vibrating sample magnetometer (VSM). The adsorption performance of the adenine-coated magnetic carbon nanotubes was evaluated via adsorption isotherms, the kinetics and selectivity tests. The adsorption capacity of the adenine-functionalized sorbent for aristolochic acid Ⅰ was determined to be 24.5 µg mg-1. By combining magnetic solid phase extraction with HPLC detection, a method was developed to enrich and detect aristolochic acids used in traditional Chinese medicine. A satisfactory recovery (92.7 - 97.5% for aristolochic acid Ⅰ and 92.6 - 99.4% for aristolochic acid Ⅱ) and an acceptable relative standard deviation (<4.0%) were obtained.


Assuntos
Adenina/química , Ácidos Aristolóquicos/isolamento & purificação , Fenômenos Magnéticos , Nanotubos de Carbono/química , Adsorção , Medicamentos de Ervas Chinesas/química , Compostos Férricos/síntese química , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Cinética , Nanocompostos/química , Nanotubos de Carbono/ultraestrutura , Concentração Osmolar , Reprodutibilidade dos Testes , Dióxido de Silício/síntese química , Dióxido de Silício/química , Extração em Fase Sólida , Temperatura , Difração de Raios X
11.
Mater Sci Eng C Mater Biol Appl ; 115: 111063, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32600689

RESUMO

Nowadays, the research on the recognition and separation of proteins has attracted extensive attention in the fields of materials science, bioengineering and life science. Protein imprinted polymers are ideal recognition materials, due to its high selectivity, good stability, easy preparation, and low cost. Herein, novel surface imprinting biowaste-derived molecularly imprinted polymers (BD-MIPs) were synthesized for specific recognition and purification of lysozyme (Lyz). This is the first time that magnetic pomegranate rind-derived carbon was used as a carrier to immobilize Lyz. Then, with the self-polymerization of dopamine, a large number of biocompatible recognition sites were generated under mild conditions. The physical/chemical properties and surface morphologies of the synthetic BD-MIPs were characterized, indicating that the imprinted film was successfully synthesized, and the BD-MIPs had good thermal stability and magnetic property. To investigate the recognition performance of BD-MIPs, four adsorption experiments were performed. The results show that BD-MIPs had a high adsorption capacity of 301.87 mg g-1, fast equilibrium time within 40 min, satisfactory selectivity and good reusability for Lyz. Furthermore, the practicability of BD-MIPs was confirmed by the isolation of Lyz from a biological sample. The good adsorption capacity and gentle one-step preparation make the BD-MIPs attractive for Lyz recognition, which shows potential values in basic biomedical research, industrial protein purification and clinical diagnostics.


Assuntos
Materiais Biocompatíveis/síntese química , Polímeros Molecularmente Impressos/síntese química , Muramidase/isolamento & purificação , Romã (Fruta)/química , Adsorção , Animais , Materiais Biocompatíveis/química , Galinhas , Clara de Ovo/análise , Fenômenos Magnéticos , Polímeros Molecularmente Impressos/química , Resíduos
12.
Adv Healthc Mater ; 9(11): e2000527, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32364331

RESUMO

Transdermal delivery of water-insoluble drugs via hydrogel-based microneedle (MN) arrays is crucial for improving their therapeutic efficacies. However, direct loading of water-insoluble drug into hydrophilic matrices remains challenging. Here, a biodegradable MN array patch that is fabricated from naturally derived polymer conjugates of gelatin methacryloyl and ß-cyclodextrin (GelMA-ß-CD) is reported. When curcumin, an unstable and water-insoluble anticancer drug, is loaded as a model drug, its stability and solubility are improved due to the formation of an inclusion complex. The polymer-drug complex GelMA-ß-CD/CUR can be formulated into MN arrays with sufficient mechanical strength for skin penetration and tunable drug release profile. Anticancer efficacy of released curcumin is observed in three-dimensional B16F10 melanoma models. The GelMA-ß-CD/CUR MN exhibits relatively higher therapeutic efficacy through more localized and deeper penetrated manner compared with a control nontransdermal patch. In vivo studies also verify biocompatibility and degradability of the GelMA-ß-CD MN arrays patch.


Assuntos
Gelatina , beta-Ciclodextrinas , Administração Cutânea , Sistemas de Liberação de Medicamentos , Agulhas , Água
13.
J Colloid Interface Sci ; 573: 115-122, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278170

RESUMO

Exploitation of novel photocatalysts for highly efficient degradation of organic dyes and reduction of hexavalent chromium is of significance to reduce environmental pollution. Herein, a novel three-dimensional flower-like Bi2S3 nanocrystals composed of two-dimensional Bi2S3 nanosheets were prepared by one-pot hydrothermal method with polyvinyl pyrrolidone (Mw = 1300000) as a capping agent. The experimental results show that polyvinyl pyrrolidone has evident enhanced effect on the photocatalytic performance of Bi2S3, and the polyvinyl pyrrolidone modified three-dimensional Bi2S3 (Bi2S3-1) displays extraordinary catalytic activity for photodegradation of rhodamine B and photoreduction of Cr(VI) under visible light. The rates of photodegradating rhodamine B and photoreducing Cr(VI) with Bi2S3-1 can reach 93.9% in 30 min (k = 0.07675 min-1) and 95.2% in 5 min (k = 0.47351 min-1), respectively. The photocatalytic performance of polyvinyl pyrrolidone modified three-dimensional Bi2S3 is much better than those of previously reported bismuth-based nanostructures. This work provides a new insight into the development of inorganic photocatalysts for both degradation of organic dyes and reduction of heavy metal ions.

14.
Adv Drug Deliv Rev ; 165-166: 41-59, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31837356

RESUMO

Microneedles (MNs) have been used to deliver drugs for over two decades. These platforms have been proven to increase transdermal drug delivery efficiency dramatically by penetrating restrictive tissue barriers in a minimally invasive manner. While much of the early development of MNs focused on transdermal drug delivery, this technology can be applied to a variety of other non-transdermal biomedical applications. Several variations, such as multi-layer or hollow MNs, have been developed to cater to the needs of specific applications. The heterogeneity in the design of MNs has demanded similar variety in their fabrication methods; the most common methods include micromolding and drawing lithography. Numerous materials have been explored for MN fabrication which range from biocompatible ceramics and metals to natural and synthetic biodegradable polymers. Recent advances in MN engineering have diversified MNs to include unique shapes, materials, and mechanical properties that can be tailored for organ-specific applications. In this review, we discuss the design and creation of modern MNs that aim to surpass the biological barriers of non-transdermal drug delivery in ocular, vascular, oral, and mucosal tissue.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31878121

RESUMO

Griseofulvin (GSF) is clinically employed to treat fungal infections in humans and animals. GSF was detected in surface waters as a pharmaceutical pollutant. GSF detection as an anthropogenic pollutant is considered as a possible source of drug resistance and risk factor in ecosystem. To address this concern, a new extraction and enrichment method was developed. GSF-surface molecularly imprinted polymers (GSF-SMIPs) were prepared and applied as solid phase extraction (SPE) sorbent. A dispersive solid phase extraction (DSPE) method was designed and combined with HPLC for the analysis of GSF in surface water samples. The performance of GSF-SMIPs was assessed for its potential to remove GSF from water samples. The factors affecting the removal efficiency such as sample pH and ionic strength were investigated and optimized. The DSPE conditions such as the amount of GSF-SMIPs, the extraction time, the type and volume of desorption solvents were also optimized. The established method is linear over the range of 0.1-100 µg/mL. The limits of detection and quantification were 0.01 and 0.03 µg/mL respectively. Good recoveries (91.6-98.8%) were achieved after DSPE. The intra-day and inter-day relative standard deviations were 0.8 and 4.3% respectively. The SMIPs demonstrated good removal efficiency (91.6%) as compared to powder activated carbon (67.7%). Moreover, the SMIPs can be reused 10 times for water samples. This is an additional advantage over single-use activated carbon and other commercial sorbents. This study provides a specific and sensitive method for the selective extraction and detection of GSF in surface water samples.


Assuntos
Antifúngicos/química , Cromatografia Líquida de Alta Pressão/métodos , Recuperação e Remediação Ambiental/métodos , Griseofulvina/química , Polímeros/química , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/química
16.
Analyst ; 145(1): 268-276, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31746832

RESUMO

Immobilized enzymes play significant roles in many practical applications. However, the enzymes need to be purified before immobilization by conventional immobilizing methods, and the purification process is expensive, laborious, complicated and results in a decrease of the enzymatic activity. So, we present a novel method by a facile one-step targeted immobilization of an enzyme without a purification process from complex samples. For this purpose, a novel molecularly imprinted polymer was prepared via a silane emulsion self-assembly method using boric acid-modified Fe3O4 nanoparticles as magnetic nuclei, horseradish peroxidase as a template, 3-aminopropyltriethoxysilane as a functional monomer and tetraethyl orthosilicate as a crosslinking agent. The molecularly imprinted polymers were characterized using a scanning electron microscope, X-ray photoelectron spectroscope, vibrating sample magnetometer and X-ray diffractometer. The as-prepared and characterized materials were employed to immobilize horseradish peroxidase from a crude extract of horseradish. Moreover, the immobilized horseradish peroxidase was employed to develop visual sensors for the detection of glucose and sarcosine. This study demonstrated that the molecularly imprinted polymers prepared via the silane emulsion self-assembly method can facilely immobilize horseradish peroxidase from a crude extract of horseradish without any purification process. The developed visual method based on the immobilized horseradish peroxidase shows great potential applications for the visual detection of glucose and sarcosine.


Assuntos
Glicemia/análise , Colorimetria/métodos , Enzimas Imobilizadas/química , Peroxidase do Rábano Silvestre/química , Polímeros/química , Sarcosina/urina , Armoracia/enzimologia , Benzidinas/química , Glicemia/química , Corantes/química , Emulsões/química , Glucose Oxidase/química , Humanos , Peróxido de Hidrogênio/química , Nanopartículas de Magnetita/química , Impressão Molecular , Propilaminas/química , Sarcosina/química , Sarcosina Oxidase/química , Silanos/química
17.
Anal Sci ; 35(12): 1317-1325, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31406026

RESUMO

Pyrrolizidine alkaloids are secondary metabolites of plants and can cause significant hepatotoxicity in humans. In this study, a fast and simple method was developed to determine ten pyrrolizidine alkaloids (PAs) in six types of herbal medicines using ultra performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF-MS). An efficient solid-phase extraction procedure was carried out by using strong cation-exchange cartridges and the parameters were optimized. The established analytical method was validated and the results showed that the method presented satisfactory accuracy and precision. The established method was successfully applied for the determination of PAs in six herbal plants, including Senecionis Scandentis Hebra, Arnebiae Radix, Asteris Radix Et Rhizoma, Farfarae Flos, Senecionis Cannabifolii Herba and Emilia sonchifolia. PAs were found in all of these herbal plant samples. Eight types of related commercial herbal drugs were also detected, six of them were detected with different amounts of PAs. This work not only provided a powerful technical platform for both qualitative and quantitative analysis of PAs in herbal medicines, but also obtained information concerning PAs in these herbal samples, which could provide reference to the government regulatory authorities and non-governmental organizations.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas/métodos , Alcaloides de Pirrolizidina/análise , Alcaloides de Pirrolizidina/isolamento & purificação , Extração em Fase Sólida/métodos , Métodos Analíticos de Preparação de Amostras , Troca Iônica , Reprodutibilidade dos Testes
19.
J Sep Sci ; 42(21): 3352-3362, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31453662

RESUMO

Pyrrolizidine alkaloids are the most widely distributed natural toxins, and pyrrolizidine alkaloid-containing herbal medicines are probably the most common poisonous plants affecting humans. We reported pyrrolizidine alkaloid-molecularly imprinted polymer solid-phase microextraction for the selective adsorption of toxic pyrrolizidine alkaloids from herbal medicine. A sulfonic compound, sodium allylsulfonate, was chosen as the functional monomer to interact with pyrrolizidine alkaloids through strong ionic interaction. To avoid template leakage and for the aim of cost saving, a relatively cheap dummy template was used for the fabrication of molecularly imprinted polymer-solid-phase microextraction fibers. The obtained fibers showed selective adsorption ability for four pyrrolizidine alkaloids, including europine, echimidine, lasiocarpine, and heliotrine. The extraction parameters, such as extraction time, extraction temperature, shaking speed, elution solvent and elution time, were optimized. Then ultra high performance liquid chromatography with mass spectrometry coupled with molecularly imprinted polymer-solid-phase microextraction method was developed for the fast and efficient analysis of four pyrrolizidine alkaloids from the model herbal plant Farfarae Flos. The established method was validated and exhibited satisfactory accuracy and precision. The present method provides an innovative and fast analytical strategy for the determination of trace toxic pyrrolizidine alkaloids in complicated samples.


Assuntos
Impressão Molecular , Polímeros/química , Alcaloides de Pirrolizidina/análise , Microextração em Fase Sólida , Tussilago/química , Adsorção , Cromatografia Líquida de Alta Pressão , Medicina Herbária , Estrutura Molecular , Tamanho da Partícula , Polímeros/síntese química , Propriedades de Superfície , Espectrometria de Massas em Tandem
20.
Chem Commun (Camb) ; 55(19): 2789-2792, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30758352

RESUMO

Novel rhombic dodecahedral SnS nanocrystals were prepared via a facile one-pot hydrothermal method for the first time, which exhibit a large extinction coefficient of 36.8 L g-1 cm-1 and a high photothermal conversion efficiency of 39.4% under irradiation with a 785 nm laser. Moreover, they show good performance for photothermal therapy of HeLa tumors.


Assuntos
Lasers , Nanopartículas Metálicas/química , Sulfetos/química , Compostos de Estanho/química , Animais , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Nus , Fototerapia , Temperatura , Transplante Heterólogo , Neoplasias do Colo do Útero/terapia
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