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1.
ACS Appl Bio Mater ; 7(5): 3154-3163, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38695332

RESUMO

ß-Galactosidase (ß-Gala) is an essential biomarker enzyme for early detection of breast tumors and cellular senescence. Creating an accurate way to monitor ß-Gala activity is critical for biological research and early cancer detection. This work used fluorometric, colorimetric, and paper-based color sensing approaches to determine ß-Gala activity effectively. Via the sensing performance, the catalytic activity of ß-Gala resulted in silicon nanoparticles (SiNPs), fluorescent indicators obtained via a one-pot hydrothermal process. As a standard enzymatic hydrolysis product of the substrate, kaempferol 3-O-ß-d-galactopyranoside (KOßDG) caused the fluorometric signal to be attenuated on kaempferol-silicon nanoparticles (K-SiNPs). The sensing methods demonstrated a satisfactory linear response in sensing ß-Gala and a low detection limit. The findings showed the low limit of detection (LOD) as 0.00057 and 0.098 U/mL for fluorometric and colorimetric, respectively. The designed probe was then used to evaluate the catalytic activity of ß-Gala in yogurt and human serum, with recoveries ranging from 98.33 to 107.9%. The designed sensing approach was also applied to biological sample analysis. In contrast, breast cancer cells (MCF-7) were used as a model to test the in vitro toxicity and molecular fluorescence imaging potential of K-SiNPs. Hence, our fluorescent K-SiNPs can be used in the clinic to diagnose breast cellular carcinoma, since they can accurately measure the presence of invasive ductal carcinoma in serologic tests.


Assuntos
Neoplasias da Mama , Quempferóis , Teste de Materiais , Nanopartículas , Silício , beta-Galactosidase , Humanos , beta-Galactosidase/metabolismo , Silício/química , Células MCF-7 , Nanopartículas/química , Quempferóis/química , Quempferóis/farmacologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Tamanho da Partícula , Colorimetria , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química , Feminino , Estrutura Molecular
3.
J Agric Food Chem ; 71(40): 14814-14824, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37782472

RESUMO

Residues of endocrine disrupting steroid hormones in food might cause various diseases like cardiovascular diseases and breast and prostate cancers. Monitoring steroid hormone levels plays a vital role in ensuring food safety and exploring the pathogenic mechanism of steroid hormone-related diseases. Based on the Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click reaction, a novel chemoselective probe, Azo-N3, which contains a reactive site N3, an imidazolium salt-based MS tag, and an azobenzene-based photoswitchable handle, was designed and synthesized to label ethynyl-bearing steroid hormones. The probe Azo-N3 was applied for the highly selective and sensitive detection of four ethynyl-bearing steroid hormones in food samples (milk, egg, and pork) by using ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The ionization efficiency of the labeled analytes could be increased by 6-105-fold, and such a labeled method exhibited satisfactory detection limits (0.04-0.2 µg/L), recovery (80.6-122.4%), and precision (RSDs% lower than 6.9%). Interestingly, the efficient immobilization of the probe Azo-N3 onto α-cyclodextrin (α-CD)-modified magnetic particles to construct a solid supported chemoselective probe Fe3O4-CD-Azo-N3 and UV light-controlled release of the labeled analytes from a magnetic support can be achieved by taking advantage of the photoswitched host-guest inclusion between the azobenzene unit and α-CD. The potential applications of Fe3O4-CD-Azo-N3 for labeling, capturing, and the photocontrolled release of the labeled steroid hormones were fully investigated by mass spectrometry imaging analysis. This work not only provides a sensitive and accurate method to detect steroid hormones in food but also opens a new avenue in designing solid supported chemoselective probes.


Assuntos
Hormônios , Espectrometria de Massas em Tandem , Humanos , Masculino , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Esteroides/química , Cromatografia Líquida de Alta Pressão/métodos
4.
Anal Chim Acta ; 1280: 341880, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37858561

RESUMO

ß-Glucosidase (ß-Gluco) is an enzyme that is crucial to numerous diseases, including cancer, and in sector of industries, it is used in the manufacturing of food. Measuring its enzymatic activity is critical for biomedical studies and other activities. Herein, we have developed a novel and precise fluorescent sensing method for measuring ß-Gluco activity based on the production of yellow-green fluorescent quercetin-silicon nanoparticles (Q-SiNPs) produced from quercetin (QN) as a reducing agent and 3-[2-(2-aminoethyl amino) ethylamino] propyl-trimethoxy silane (AEEA) as a silane molecule. ß-Gluco hydrolyzed quercetin-3-O-ß-d-glucopyranoside (QO-ß-DG) to produce QN, which was then used to produce Q-SiNPs. Reaction parameters, including temperature, time, buffer, pH, and probe concentration, were carefully tuned in this study. Subsequently, the fluorescence intensity was performed, showing good linearity (R2 = 0.989), a broad linear dynamic range between 0.5 and 12 U L-1, and a limit of detection (LOD) as low as 0.428 U L-1, which was proven by fluorescence measurements. Most importantly, various parameters were detected and characterized with or without ß-Gluco. The designed probe was successively used to assess ß-Gluco activity in human serum and moldy bread. However, the mathematical findings revealed recoveries for human serum ranging from 99.3 to 101.66% and for moldy bread from 100.11 to 102.5%. Additionally, Q-SiNPs were well suited to being incubated in vitro with L929 and SiHa living cells, and after using an Olympus microscope, imaging showed good fluorescence cell images, and their viability evinced minimal cytotoxicity of 77% for L929 and 88% for SiHa. The developed fluorescence biosensor showed promise for general use in diagnostic tests. Therefore, due to this outstanding sensing modality, we anticipate that this research can provide a novel schematic project for creating simple nanostructures with a suitable plan and a green synthetic option for enzyme activity and cell imaging.


Assuntos
Celulases , Nanopartículas , Humanos , Quercetina , Silício/química , Silanos , Nanopartículas/química , Corantes Fluorescentes/química
5.
Nanoscale ; 14(27): 9806-9817, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35770915

RESUMO

Bacterial infections can cause serious complications in cancer treatment and have been proven to weaken therapeutic benefits. Recently, antibacterial nanomaterials that serve as carriers for anticancer drug delivery have been attracting extensive interest due to their combined antimicrobial and anticancer activities. In this study, antibacterial metal-phenolic nanosheets (Cu-TA) were successfully prepared via the self-assembly of the metal-phenolic coordination complexes formed between copper ions and tannic acid, and the structure, morphology, and formation mechanism of Cu-TA nanosheets were explored. The antibacterial activity of Cu-TA nanosheets against both Gram-positive and Gram-negative bacteria was detected using the minimum inhibitory concentration (MIC), zone of inhibition and plate counting methods. The MIC values of both bacterial strains were about 0.4 mg mL-1, and the killing rates of Cu-TA samples were close to 100% at the concentration of 2 and 0.2 mg mL-1 after 12-hour incubation. Epirubicin hydrochloride (EPI) molecules were successfully loaded on the porous Cu-TA nanosheets mainly through the formation of the Cu-EPI chelate complex and strong electrostatic interactions. The Cu-EPI complex and Cu-TA nanosheets could be disassembled under acidic conditions or in the presence of high levels of glutathione (GSH) after uptake by cancer cells, which triggered the unique pH and GSH-responsive controlled release behaviors of EPI and copper ions. The MTT assay results revealed that the presence of bacteria in Hep G2 cells can greatly impair the cell death rate induced by free EPI, but the resultant EPI-loaded Cu-TA nanosheets can significantly enhance cell death both in the presence and absence of bacteria.


Assuntos
Antibacterianos , Cobre , Antibacterianos/química , Bactérias , Cobre/química , Preparações de Ação Retardada/farmacologia , Epirubicina/química , Epirubicina/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Metais/química
6.
J Chromatogr A ; 1651: 462302, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34119720

RESUMO

Phospholipids are one of the main nutrients in rice, which have a positive effect on cancer, coronary heart disease and inflammation. However, phospholipids will become small molecular volatile substances during the aging process of rice, resulting in change the flavor of rice. Therefore, mapping the concentration and the spatial distribution of phospholipids in rice are of tremendous significance in its function research. In this work, we established a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) imaging method for the spatial distribution analysis of phospholipids in rice. A total of 12 phospholipid compounds were found in the range of m/z 500-1000 through a series of conditions optimization. According to the results, lysophosphatidylcholine (LPC) species spread throughout the rice tissue sections and phosphatidylcholine (PC) species distributed in the bran and embryo (particularly in the scutellum). We also compared the signal intensities of phospholipids in different parts of white rice and brown rice by region of interest (ROI) analysis, which showed the relative content of PC species was higher in the embryo and gradually decreased until disappeared with the increase of processing degree during the processing of brown rice to white rice. The PC species on the surface of rice could be used as an important indicator to identify the processing degree of rice. Our work not only establish a MALDI-TOF-MS imaging method for spatial distribution analysis of rice, but also provide the necessary reference for ensuring food security, improving the eating quality of rice and the health benefits of consumers.


Assuntos
Análise de Alimentos/métodos , Oryza/química , Fosfolipídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Lasers , Lisofosfatidilcolinas/análise , Fosfatidilcolinas/análise
7.
J Mater Chem B ; 9(14): 3200-3209, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33885624

RESUMO

Making full use of the undeveloped bioactive natural product derivatives by selectively delivering them to target sites can effectively increase their druggability and reduce the wastage of resources. Azo-based prodrugs are widely regarded as an effective targeted delivery means for colon-related disease treatment. Herein, we report a new-type of azo-based nanoprodrug obtained from bioactive natural products, in which the readily available podophyllotoxin natural products are connected with methoxy polyethylene glycol (mPEG) via a multifunctional azobenzene group. The amphiphilic prodrug can form nanosized micelles in water and will be highly selectively activated by azoreductases, leading to the in situ generation of anticancer podophyllotoxin derivatives (AdP) in the colon after the cleavage of the azo bond. To satisfy the demand of drug carriers for cancer combination therapy in clinics, α-CD is further introduced into this nanoprodrug micelle system to form a supramolecular hydrogel via a cascade self-assembly strategy. Using imaging mass spectrometry (IMS), the colon-specific drug release ability of the hydrogel after oral administration is demonstrated at the molecular level. Finally, the nanoprodrug hydrogel is further used as a carrier to load a hydrophilic anti-cancer drug 5-FU during the hierarchical self-assembly process and to co-deliver AdP and 5-FU for the drug combination. The combination use of AdP and 5-FU provides enhanced cytotoxicity which indicates a significant synergistic interaction. This work offers a new way to enhance the therapeutic effect of nanoprodrugs via drug combination, and provides a new strategy for reusing bioactive natural products and their derivatives.


Assuntos
Antineoplásicos/farmacologia , Hidrogéis/química , Nanopartículas/química , Podofilotoxina/farmacologia , Pró-Fármacos/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Hidrogéis/síntese química , Micelas , Estrutura Molecular , Tamanho da Partícula , Podofilotoxina/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Células Vero
8.
Front Genet ; 12: 827444, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35111208

RESUMO

Gastric cancer is a common cancer afflicting people worldwide. Although incremental progress has been achieved in gastric cancer research, the molecular mechanisms underlying remain unclear. In this study, we conducted bioinformatics methods to identify prognostic marker genes associated with gastric cancer progression. Three hundred and twenty-seven overlapping DEGs were identified from three GEO microarray datasets. Functional enrichment analysis revealed that these DEGs are involved in extracellular matrix organization, tissue development, extracellular matrix-receptor interaction, ECM-receptor interaction, PI3K-Akt signaling pathway, focal adhesion, and protein digestion and absorption. A protein-protein interaction network (PPI) was constructed for the DEGs in which 25 hub genes were obtained. Furthermore, the turquoise module was identified to be significantly positively coexpressed with macrophage M2 infiltration by weighted gene coexpression network analysis (WGCNA). Hub genes of COL1A1, COL4A1, COL12A1, and PDGFRB were overlapped in both PPI hub gene list and the turquoise module with significant association with the prognosis in gastric cancer. Moreover, functional analysis demonstrated that these hub genes play pivotal roles in cancer cell proliferation and invasion. The investigation of the gene markers can help deepen our understanding of the molecular mechanisms of gastric cancer. In addition, these genes may serve as potential prognostic biomarkers for gastric cancer diagnosis.

9.
Analyst ; 145(22): 7397-7405, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-32935670

RESUMO

In this work, acid and matrix-tolerant multifunctionalized gold nanoparticles (AuNPs) with an integrated chiral selector towards tyrosine (Tyr) and polyethylenglycol (PEG) chains were developed for visual chiral discrimination of Tyr in biological samples under acid conditions. In brief, AuNPs multifunctionalized with N-acetyl-l-cysteine (NALC) and PEG (PEG/NALC-AuNPs) were prepared via a simple strategy. In the presence of l-Tyr, the color of PEG/NALC-AuNP solution changed from red to gray, while no obvious color change was observed with the introduction of d-Tyr, which indicated that the introduction of PEG onto the surface of AuNPs has no effect on the chiral recognition between l-Tyr and NALC. A computer-aided molecular model was used to clarify the chiral recognition mechanism between NALC and Tyr enantiomers and to further guide the optimization of sensitivity. The resultant PEG/NALC-AuNP sensor presented a significantly improved stability under acid and alkali conditions compared with conventional NALC-AuNPs, resulting in a wider dynamic range (500 nM-100 µM) and a 50 times reduced detection limit by simply adjusting the pH of the sensor system under acid conditions (pH 2-2.5). More importantly, the PEG/NALC-AuNPs can realize the visual chiral discrimination of Tyr enantiomers in biological samples due to their significantly improved long-term stability and reduced interaction towards non-target species.


Assuntos
Ouro , Nanopartículas Metálicas , Acetilcisteína , Colorimetria , Polietilenoglicóis , Tirosina
10.
Anal Chem ; 92(13): 9039-9047, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32501673

RESUMO

We report the development of an azoreductase-responsive prodrug AP-N═N-Cy in which the precursor compound AP, a readily available podophyllotoxin derivative, is linked with a NIR fluorophore (Cy) via a multifunctional azobenzene group. This type of azo-based prodrug can serve as not only an azoreductase-responsive NIR probe to real-time tracking of the drug delivery process but also a delivery platform for an anticancer compound (AdP). We have shown that cleavage of the multifunctional azobenzene group in AP-N═N-Cy only occurred in the presence of azoreductase, which specifically secretes in the colon, resulting in direct release of AdP through an in situ modification of a phenylamino group on the precursor AP. Moreover, introduction of the azobenzene group endows the prodrug with an unique fluorescence "off-on" property and served as a switch to "turn on" the fluorescence of Cy as consequence of a self-elimination reaction with breakage of an azo bond. Such a prodrug can be administered orally and exhibit high stability and low toxicity before arriving at the colon. In view of the synchronism of drug release and the fluorescence turn-on process, the fluorescence imaging method was utilized to precisely trace drug delivery in vitro, ex vivo, and in vivo. Distinguishingly, the biodistribution of AdP and Cy in various tissues was further precisely mapped at the molecular level using imaging mass spectrometry. To the best of our knowledge, this is the first time that the in vivo real-time precise tracking of the colon-specific drug release and biodistribution was reported via a multimodal imaging method.


Assuntos
Compostos Azo/química , Colo/diagnóstico por imagem , Portadores de Fármacos/química , NADH NADPH Oxirredutases/metabolismo , Imagem Óptica/métodos , Pró-Fármacos/química , Animais , Compostos Azo/metabolismo , Carbocianinas/química , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Corantes Fluorescentes/química , Humanos , Cinética , Espectrometria de Massas , Camundongos , Microscopia Confocal , Nitrorredutases , Pró-Fármacos/metabolismo , Distribuição Tecidual
11.
Mikrochim Acta ; 187(1): 76, 2019 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-31872371

RESUMO

Multilayered and porous sodium-doped graphitic carbon nitride (GCN-Na) was prepared and employed to the solid-phase extraction of Sr(II). The sorbent exhibits high adsorption capacity and excellent selectivity for Sr(II). This is due to its small interplanar stacking distance caused by doping with Na(I) which matches the size of Sr(II) better than blank GCN. An original solid-phase extraction method based on GCN-Na coupled with ICP-OES was established for Sr(II), the calibration plots are linear ranging from 0.05-10 mg·kg-1 with the correlation coefficients (R2) above 0.999, the limits of detection are in the range of 0.57-1.52 µg·kg-1 and the preconcentration factor of 80 is achieved using 48 mL sample. It was successfully applied in the extraction and detection of trace Sr(II) in tap water, rice and sea fish. Graphical abstractA multilayer porous sodium(I) doped graphitic carbon nitride nanosheet (GCN-Na) was synthesized and exhibited excellent adsorption capability and selectivity for Sr(II).

12.
J Mater Chem B ; 7(40): 6187-6194, 2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31565721

RESUMO

MIT is a promising strategy in antibody free analysis for tumour markers. Conventional nanosized MIPs with off-line analysis are beset by tedious operation and unsatisfactory analysis performance. In this work, an on-line analytical device to directly detect AFP, which is a typical tumour marker in cancer screening, was prepared for the first time. A microscope slide was chosen to be the basis of the device. APBA-PA, a polymerizable fluorescent boronic acid monomer, was synthesised and grafted on the surface of the microscope slide to act as the signal transduction pathway between the templates and the device. Along with the hydrolysis of TEOS and the elution of the templates, a portable, stable, easy to operate and low-cost analysis device for AFP with excellent repeatability was successfully prepared. Owing to the excellent selectivity and highly sensitive fluorescence response ability of the device towards the templates, the on-line detection of AFP in human serum was realized. A series of characterizations were applied to the device, and its analysis performance and possible detection mechanism were carefully studied. Furthermore, the device exhibited appropriate application prospects by comparing its analysis results with those of the commercially available ELISA. In our perception, this work is an important step towards MIPs for clinical applications.


Assuntos
Corantes Fluorescentes/química , Impressão Molecular/instrumentação , Impressão Molecular/métodos , Polímeros/química , alfa-Fetoproteínas/análise , Humanos , Limite de Detecção , Sistemas On-Line
13.
ACS Appl Mater Interfaces ; 10(25): 21149-21159, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29874031

RESUMO

The development of codelivery systems for combination therapy that can load different drugs in a single carrier and precisely deliver payloads (ratio and administration time) via programmable administration has proven to be challenging. By taking advantage of the increased dimension or space from particle self-assembly approach, we have developed a prodrug-based cascade self-assembly strategy to construct a supramolecular hydrogel that can load different drugs in stages yet temporally/spatially release drugs by cascade disassembly of supramolecular hydrogel under different microenvironments. The cascade self-assembly mechanism has been investigated in detail by morphology evolution of prodrug micelles. Using tumor cell uptake, cytotoxicity assay, and a tumor-bearing animal model, the effectiveness of the prodrug micelle-based cascade self-assembly system was studied, such as loading, controlling the drug ratio, and the administration time for possible therapeutic applications. These studies fully demonstrate the proof of concept and open up an attractive new way to construct multidrug-loaded carriers for combination therapy.


Assuntos
Pró-Fármacos/química , Animais , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Quimioterapia Combinada , Micelas , Neoplasias
14.
Molecules ; 21(12)2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-27941678

RESUMO

Xanthoceras sorbifolia Bunge. is used in traditional medicine in North China. To evaluate the anti-tumor and radical-scavenging activities of X. sorbifolia husks polyphenols and determine their structure-activity relationships, 37 polyphenols 1-37 were obtained by bioassay-guided fractionation. Two new compounds 1-2, and compounds 5, 6, 8, 9, 11, 14-17, 21-25, 27-29, 31, 33, 34, 36, and 37 were isolated from the genus Xanthoceras for the first time. Compounds 1-37 did not show strong cytotoxicity against the four tested tumor cell lines (A549, HepG2, MGC-803, and MFC) compared to paclitaxel and under the conditions tested in the anti-tumor assay, but compounds 3, 4, 7, 8, 10, 18-20, 25, 26, 29, 30, 32, and 35 exhibited stronger radical-scavenging activity than ascorbic acid in a 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt assay. This was the first report on the anti-tumor and radical-scavenging activities of the polyphenols isolated from X. sorbifolia husks. Overall, the present study contributed valuable information concerning X. sorbifolia husks use in medicine and pharmacology.


Assuntos
Antineoplásicos Fitogênicos , Sequestradores de Radicais Livres , Neoplasias/tratamento farmacológico , Polifenóis , Sapindaceae/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Células Hep G2 , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Polifenóis/química , Polifenóis/isolamento & purificação , Polifenóis/farmacologia
15.
Chem Commun (Camb) ; 52(100): 14384-14387, 2016 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-27886300

RESUMO

A three dimensional supramolecular hydrogel consisting of prodrug-modified graphene oxide and α-cyclodextrin was developed. This hydrogel with a well-ordered interior microstructure integrated hydrophobic and hydrophilic anticancer drugs into a single multifunctional platform, and underwent a gel-sol transition leading to cascade release of two drugs in an on-demand fashion upon NIR light irradiation.


Assuntos
Antineoplásicos/administração & dosagem , Camptotecina/administração & dosagem , Preparações de Ação Retardada/química , Fluoruracila/administração & dosagem , Grafite/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Animais , Antineoplásicos/farmacocinética , Camptotecina/farmacocinética , Sistemas de Liberação de Medicamentos , Fluoruracila/farmacocinética , Raios Infravermelhos , Camundongos , Óxidos/química
16.
J Mater Chem B ; 4(15): 2620-2627, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32263286

RESUMO

Antibody-free analysis is a potential method for glycoprotein analysis, but the development of this method has been limited by its unfavorable selectivity in recent years. Magnetic molecular imprinting, which integrates the fast separation of magnetic materials with high selectivity towards templates in molecular imprinting, was expected to be an effective sample pretreatment in antibody-free analysis for glycoproteins. However, the aggregation of magnetic imprinted nanoparticles and thick molecularly imprinted polymer (MIP) shells on the surface of magnetic carriers caused an unfavorable adsorption capacity, and unsatisfactory rebinding and elution rates, and has limited its application in glycoprotein extraction. Thus, highly dispersed magnetic molecularly imprinted nanoparticles (MMINs) with a well-defined thin film for the selective extraction of glycoprotein HRP were developed in this work. A solvothermal method was used in this work to improve the dispersity of Fe3O4 NPs (nanoparticles) and the MMINs. The thickness of the MIP film was optimized to provide the optimum extraction efficiency. Thus the adsorption capacity of the MMINs, the rebinding rate and the elution rate of the templates were greatly improved. As a result, the prepared MMINs not only exhibited excellent selectivity and high adsorption capacity to HRP, and an outstanding tolerance for interference, but also showed excellent rebinding and elution rates for extraction application. Furthermore, this method provided a reliable way to improve conventional magnetic molecular imprinting, and showed great potential for the analysis of glycoprotein tumor biomarkers in clinics in the future.

17.
ACS Appl Mater Interfaces ; 6(22): 19544-51, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25372156

RESUMO

In this work, we developed a simple, novel method for constructing gold nanocomposite supramolecular hybrid hydrogels for drug delivery, in which gold nanocrystals were utilized as building blocks. First, methoxypoly(ethylene glycol) thiol (mPEG-SH, molecular weight (MW)=5 K) capped gold nanocrystals (nanospheres and nanorods) were prepared via a facile one-step ligand-exchange procedure. Then, the homogeneous supramolecular hybrid hydrogels were formed, after adding α-cyclodextrin (α-CD) into PEG-modified gold nanocrystal solutions, due to the host-guest inclusion. Both gold nanoparticles and inclusion complexes formed between α-CD and PEG chain provided the supra-cross-links, which are beneficial to the gelation formation. The resulting hybrid hydrogels were fully characterized by a combination of techniques including X-ray diffraction, rheology studies, and scanning electron microscopy. Meanwhile, the hybrid hydrogel systems demonstrated unique reversible gel-sol transition properties at a certain temperature caused by the temperature-responsive reversible supramolecular assembly. The drug delivery applications of such hybrid hydrogels were further investigated in which doxorubicin was selected as a model drug for in vitro release, cytotoxicity, and intracellular release studies. We believe that the development of such hybrid hydrogels will provide new and therapeutically useful means for medical applications.


Assuntos
Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Ouro/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Doxorrubicina/administração & dosagem , Humanos , Microscopia Eletrônica de Varredura , Nanopartículas/química , Neoplasias/tratamento farmacológico , Polietilenoglicóis/química , Difração de Raios X , alfa-Ciclodextrinas/química
18.
Nanotechnology ; 25(33): 335101, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25073730

RESUMO

We developed a novel linear pH-sensitive conjugate methoxy poly(ethylene glycol)-4ß-aminopodophyllotoxin (mPEG-NPOD-I) by a covalently linked 4ß-aminopodophyllotoxin (NPOD) and PEG via imine bond, which was amphiphilic and self-assembled to micelles in an aqueous solution. The mPEG-NPOD-I micelles simultaneously served as an anticancer drug conjugate and as drug carriers. As a drug conjugate, mPEG-NPOD-I showed a significantly faster NPOD release at a mildly acidic pH of 5.0 and 4.0 than a physiological pH of 7.4. Notably, it was confirmed that this drug conjugate could efficiently deliver NPOD to the nuclei of the tumor cells and led to much more cytotoxic effects to A549, Hela, and HepG2 cancer cells than the parent NPOD. The half maximal inhibitory concentration (IC50) of mPEG-NPOD-I was about one order magnitude lower than that of the NPOD. In vivo, mPEG-NPOD-I reduced the size of the tumors significantly, and the biodistribution studies indicated that this drug conjugate could selectively accumulate in tumor tissues. As drug carriers, the mPEG-NPOD-I micelles encapsulated hydrophobic PTX with drug-loading efficiencies of 57% and drug-loading content of 16%. The loaded PTX also showed pH-triggered fast release behavior, and good additive cytotoxicity effect was observed for the PEG-NPOD-I/PTX. We are convinced that these multifunctional drug conjugate micelles have tremendous potential for targeted cancer therapy.


Assuntos
Antineoplásicos/química , Sistemas de Liberação de Medicamentos/métodos , Micelas , Polímeros/química , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Masculino , Camundongos , Nanopartículas/química , Polietilenoglicóis/química , Distribuição Tecidual
19.
Bioorg Med Chem Lett ; 24(16): 3944-7, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24997688

RESUMO

Oxidative stress imposed by reactive oxygen species plays a crucial role in pathophysiology of inflammatory diseases. In the present study, sesquiterpenoids and diterpenoids isolated from Siegesbeckia pubescens, a Chinese traditional medicine used to treat arthritis, were evaluated for inhibition of NO production in activated RAW 264.7 macrophages and FMLP/CB induced O2(·-) generation and elastase release in human neutrophils. In the former assay, sesquiterpenoids were more potent than diterpenoids. The C-4 carbonyl group in the carabrane-type sesquiterpenoid 3 and the C-9 ether linkage in the germacrane sesquiterpene 7 were associated with the enhanced potency. Also, for the active ent-kaurane type diterpenoids, esterification of 17-OH with isobutyric acid and acetylation of 18-OH affected the inhibition of O2(·-) generation and elastase release. This report is the first to describe the inhibitory effects on oxidative stress of secondary metabolites from S. pubescens. Its findings suggest that active terpenoids from the herb could be used as lead anti-inflammatory agents.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Asteraceae/química , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Óxido Nítrico/antagonistas & inibidores , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Asteraceae/metabolismo , Linhagem Celular , Diterpenos/química , Diterpenos/isolamento & purificação , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Medicina Tradicional Chinesa , Camundongos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Óxido Nítrico/biossíntese , Estresse Oxidativo/efeitos dos fármacos , Elastase Pancreática/antagonistas & inibidores , Elastase Pancreática/metabolismo , Metabolismo Secundário , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Relação Estrutura-Atividade , Superóxidos/antagonistas & inibidores , Superóxidos/metabolismo
20.
ACS Appl Mater Interfaces ; 6(13): 10623-30, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-24919142

RESUMO

Taking advantage of the strong hydrophobicity of the anticancer drug camptothecin (CPT), the CPT molecule was conjugated to a class of low-molecular-weight (MW) poly(ethylene glycol) (PEG) chains (MW = 500, 1000, and 2000), forming an amphiphilic prodrug. The CPT-PEG prodrug formed stable hydrogels based on a combination of the partial inclusion complexation between one end of the PEG blocks and α-CD and the hydrophobic aggregation of CPT groups. Meanwhile, the formed hydrogels could be loaded with water-soluble drug 5-fluorouracil (5-FU), which is always combined with CPT drugs to enhance their anticancer activity. Moreover, the hydrogel systems demonstrate unique structure-related reversible gel-sol transition properties at a certain temperature due to the reversible supramolecular assembly, and the gel-sol transition temperature could be modulated by varying the length of the PEG chain and the concentrations of α-CD, demonstrating the possibility of achieving on-demand gel-sol transitions. The structure-related reversible gel-sol transition properties were proved by rheological property, XRD, DSC, and SEM measurements. The different controlled release profiles of two different anticancer drugs showed significant temperature-dependent properties. This easily prepared supramolecular hydrogel with excellent biocompatibility and tunable temperature responsiveness has significant potential for controlled drug release applications.


Assuntos
Sistemas de Liberação de Medicamentos , Hidrogéis , Pró-Fármacos/administração & dosagem , Temperatura , Antimetabólitos Antineoplásicos/administração & dosagem , Fluoruracila/administração & dosagem , Microscopia Eletrônica de Varredura , Difração de Raios X
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