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1.
Top Curr Chem (Cham) ; 378(1): 18, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32009187

RESUMO

DNA molecules with superior flexibility, affinity and programmability have garnered considerable attention for the controllable assembly of nanoparticles (NPs). By controlling the density, length and sequences of DNA on NPs, the configuration of NP assemblies can be rationally designed. The specific recognition of DNA enables changes to be made to the spatial structures of NP assemblies, resulting in differences in tailorable optical signals. Comprehensive information on the fabrication of DNA-driven NP assemblies would be beneficial for their application in biosensing and bioimaging. This review analyzes the progress of DNA-driven NP assemblies, and discusses the tunable configurations determined by the structural parameters of DNA skeletons. The collective optical properties, such as chirality, fluorescence and surface enhanced Raman resonance (SERS), etc., of DNA-driven NP assemblies are explored, and engineered tailorable optical properties of these spatial structures are achieved. We discuss the development of DNA-directed NP assemblies for the quantification of DNA, toxins, and heavy metal ions, and demonstrate their potential application in the biosensing and bioimaging of tumor markers, RNA, living metal ions and phototherapeutics. We hihghlight possible challenges in the development of DNA-driven NP assemblies, and further direct potential prospects in the practical applications of macroscopical materials and photonic devices.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , Nanopartículas/química , Imagem Óptica/métodos , Biomarcadores Tumorais/análise , Grafite/química , Humanos , Metais/química , Análise Espectral Raman
2.
J Agric Food Chem ; 68(3): 735-741, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31895559

RESUMO

Facile fabrication of difunctional nanoparticles (NPs) for pesticide delivery and imaging is still a fascinating challenge. Here, water-dispersible difunctional NPs were developed using flash nanoprecipitation (FNP) where self-assembling amphiphilic block copolymers were used to encapsulate a highly hydrophobic model pesticide, Lambda-cyhalothrin, and the fluorescent dye Nile red. The particle size (ranging from 158 to 280 nm) and fluorescence property of NPs could be controlled by varying the flow rate or Nile red feed concentration. The aggregation state and rearrangement of the dye molecules in the NPs were also investigated. IVIS imaging and confocal laser scanning microscopy analysis demonstrated that the resulting difunctional nanopesticide particles could allow accurate in situ tracking of the pesticide on the leaf surface, while effectively avoiding interference from chlorophyll autofluorescence. The difunctional NP suspension maintained high insecticidal activity and stability. This work demonstrates the feasibility and great potential of the FNP method in universal fabrication of multifunctional NPs with in situ pesticide tracing and crop protection capabilities.


Assuntos
Nanopartículas/química , Nitrilos/química , Imagem Óptica/métodos , Praguicidas/química , Piretrinas/química , Proteção de Cultivos , Fluorescência , Tamanho da Partícula , Folhas de Planta/química , Polietilenoglicóis/química
3.
J Biomed Nanotechnol ; 16(1): 40-53, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31996284

RESUMO

In recent decades, a large number of research studies have been conducted to improve the treatment strategy against epithelial ovarian cancer, but women in advanced stage still have poor outcomes. The development of advanced treatments must be continued to overcome the limitation. Docetaxel, a semi-synthetic product derived from the Pacific Taxus extract, has been studied for many years for its potent anticancer applications. Aiming to solve the problems of its highly lipophilicity, insolubility and adverse side effects, nanocarriers were applied. Relying on the integration of nanoparticles which had optimized sizes, shapes, and surface properties, the effect of docetaxel was enhanced. In this study, we designed a novel drug loaded gel-forming nanoparticle system (Doc-NMs-hydrogel composites), which acted as a sustained drug depot for docetaxel. Docetaxel was encapsulated into MPEG-PCL and then into blank thermosensitive hydrogel Pluronic F-127. Characterization showed that the prepared Doc-NMs had high drug loading (7%), minor particle size (37 nm), relatively good water solubility. Moreover, the cytotoxicity, apoptosis induction and the antitumor effects of Doc-NMs-hydrogel composites on mice abdominal SKOV-3 ovarian cancer model were investigated in vivo. Compared with other groups, at the same dosage, Doc-NMs-hydrogel composites show better apoptosis induction and cell growth inhibition. In conclusion, the prepared Doc-NMs-hydrogel composites enhanced anti-tumor activity by increasing local docetaxel concentration, maintaining stable and sustained drug release, prolonging drug retention time in tumors, and reducing toxicity to normal tissues. Doc-NMs-hydrogel composites might have great potential clinical application in anti-ovarian cancer activity.


Assuntos
Neoplasias Ovarianas , Animais , Antineoplásicos , Linhagem Celular Tumoral , Docetaxel , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Hidrogéis , Camundongos , Micelas , Nanopartículas , Taxoides
4.
J Biomed Nanotechnol ; 16(1): 85-100, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31996288

RESUMO

Plumbagin, a natural naphthoquinone from the officinal leadwort, has recently been shown to exert promising anti-cancer effects. However, its therapeutic use is hampered by its failure to specifically reach tumors after intravenous administration, without secondary effects on normal tissues. Its poor solubility in water and rapid elimination following in vivo administration further limit its potential use. We hypothesize that the entrapment of plumbagin within PEGylated PLGA nanoparticles conjugated with transferrin, whose receptors are overexpressed on many types of cancer cells, could lead to a selective delivery of the drug to tumors following intravenous administration and enhance its chemotherapeutic effects. The objectives of this study were therefore to prepare and characterize transferrin-conjugated, PEGylated PLGA nanoparticles entrapping plumbagin, and to assess their anti-cancer efficacy in vitro as well as in tumor-bearing mice. The intravenous administration of transferrin-conjugated PEGylated PLGA nanoparticles resulted in the complete suppression of 10% of B16-F10 tumors and regression of 30% of the tumors, with improvement of the animal survival compared to controls. The treatment was well tolerated by the animals. Transferrin-bearing PEGylated PLGA nanoparticles entrapping plumbagin are therefore highly promising therapeutic systems, able to lead to tumor regression and even suppression after intravenous administration without visible toxicity.


Assuntos
Nanopartículas , Animais , Linhagem Celular Tumoral , Camundongos , Naftoquinonas , Transferrina
5.
Artigo em Chinês | MEDLINE | ID: mdl-31954387

RESUMO

Objective: To investigate the effect of isosorbide mononitrate (ISMN) targeted nanoparticles on inflammatory factors of sinusitis by establishing a rabbit model of rhinosinusitis. Methods: Thirty healthy rabbits, male and female, weighing 2.5-3.5 kg, were randomly divided into 6 groups with 5 rabbits in each group. Group A was the control group. The model of rabbit sinusitis was established in group B to F, and CT was used to confirm the model was successful. After placing tubes into the maxillary sinus in the group C to F, saline, 45 mg/ml ISMN, 45 mg/ml ISMN nanoparticles and 45 mg/ml ISMN targeted nanoparticles were used to wash the maxillary sinus, respectively. Blood samples were collected from the ear vein of rabbits on day 7, 14, 21, 28, 35 and 42 after modeling respectively. Changes in the expression levels of inflammatory factors in rabbits during the modeling process and after drug washing were detected by ELISA. After the drug intervention, the maxillary sinus mucosa was taken for real-time quantitative PCR to detect the changes in the mRNA level of inflammatory factors. SPSS 22.0 software was used to process the data. Results: Rabbit model of sinusitis was successfully established. ELISA showed that after the action of ISMN targeted nanoparticles of 1 week (42th day after modeling), the levels of (interleukin, IL) 4, IL-8, IL-17A and interferon γ (IFN-γ) in the blood were lower compared with that of 35th day after modeling, the difference was statistically significant (5.57±1.20 vs 19.73±0.68, 66.41±11.87 vs 154.68±13.13, 17.96±1.87 vs 28.23±0.80, 53.56±5.66 vs 111.93±7.29, all P<0.05). Compared with the ISMN nanoparticles and ISMN, the ISMN targeted nanoparticles reduced the levels of IL-4, IL-8, IL-17A and IFN-γ more obviously, the differences were statistically significant (13.26±1.43 vs 8.81±1.33 vs 7.14±2.16, 89.47±17.80 vs 41.07±7.77 vs 15.84±3.72, 10.28±2.07 vs 3.06±1.62 vs 1.82±0.90, 62.16±6.18 vs 35.12±4.62 vs 27.89±10.18, all P<0.05). Real-Time PCR showed that after the flushing of ISMN targeted nanoparticles, the levels of IL-4, IL-8, IL-17A and IFN-γ mRNA were lowest compared with that of the model group, ISMN nanoparticles and ISMN group. Conclusion: ISMN targeted nanoparticles can reduce the level of inflammatory factors in rabbit sinusitis model.


Assuntos
Dinitrato de Isossorbida/uso terapêutico , Nanopartículas/uso terapêutico , Sinusite/sangue , Sinusite/tratamento farmacológico , Animais , Modelos Animais de Doenças , Feminino , Interferon gama/sangue , Interleucina-17/sangue , Interleucina-4/sangue , Interleucina-8/sangue , Masculino , Coelhos , Distribuição Aleatória
6.
Zhonghua Wei Chang Wai Ke Za Zhi ; 23(1): 56-64, 2020 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-31958932

RESUMO

Objective: To explore the application of endoscopic tattooing with carbon nanoparticles in the treatment of advanced colorectal cancer (ACRC). Methods: A randomized controlled study was used. Inclusion criteria: (1) age more than 18 years old, and colorectal cancer was found for the first time and confirmed by colonoscopy and biopsy; (2) advanced colorectal cancer (preoperative TNM stage of T3/N1 or above, local unresectable lesion, M1 stage and simultaneously resectable metastatic lesion), and patients agreed to receive neoadjuvant therapy; (3) advanced colorectal cancer (TNM stage of T3/N1 or above) with simultaneous unresectable metastatic lesion, and patients refused operation and consented to chemoradiotherapy. Patients with previous abdominal surgery history, radiotherapy and chemotherapy history, urgent need for surgery or endoscopic stent placement and those with severe allergic constitution were excluded. Based on the above criteria, 120 patients diagnosed with ACRC in No.900 Hospital of the Joint Logistics Team from January 2016 to December 2017 were prospectively enrolled and randomly divided into tattoo group and non-tattoo group by random number table method. Tattoo group were tattooed within 1-7 days before chemoradiotherapy. The labeling location of the lesions: (1) if the colonoscopy could pass smoothly, 4 points were injected into the intestinal wall of the both opposite sides 1 cm cephalad and caudad of the tumor; (2) if the colorectal cavity was severely narrow and the colonoscopy could not pass, only 4 points were injected in 4 quadrants at 1 cm caudad of the tumor. Each injection point was injected with 0.1 ml carbon nanoparticles, and the size of the tumor was measured according to the range of carbon nanoparticles staining. The efficacy was evaluated after 8 weeks of chemoradiotherapy. Patients who were defined to be suitable for operation underwent operation 6 weeks after chemoradiotherapy. The following parameters were compared between two groups: lesion identification time, operation time, blood loss, distance from lesion to distal margin, the rate of first positive margin and the rate of anal sphincter preservation (rectal cancer). Among patients who had been evaluated as having no indication for surgery, those who were effective in chemoradiotherapy continued to receive chemotherapy in the original regimen; if the treatment failed, the chemotherapy regimen was replaced, and the efficacy was finally evaluated after six months [referring to the revised RECIST guidelines (version 1.1)]. Results: Three patients withdrew from this study, and 117 patients were enrolled in this study finally, including 59 cases in tattoo group and 58 cases in the non-tattoo group. There were no significant differences in baseline data between two groups (all P>0.05). All the patients had slight adverse reactions of radiotherapy and chemotherapy before operation, and could tolerate after symptomatic management without interruption of treatment. All the patients in the tattoo group had no discomfort such as fever, abdominal pain, abdominal distention, hematochezia, etc. and the intestinal mucosa could be seen clearly with black staining after being tattooed. A total of 77 patients were evaluated with surgical indications, including 39 cases in the tattoo group (tattoo-operable) and 38 cases in the non-tattoo group (non-tattoo-operatable). There were no significant differences in baseline data between the two groups (all P>0.05). Forty patients without operation indications continued chemoradiotherapy, including 20 cases in tattoo group (tattoo-inoperable) and 20 cases in non-tattoo group (non-tattoo-inoperable), whose differences in baseline data between the two groups were not significant as well (all P>0.05). No obvious edema, necrosis or abscess were found in the tattooed segments and the black spots could be seen quickly and clearly on the serosa of rectum in tattoo-operable patients. As compared to non-tattoo group, tattoo group had significantly shorter lesion identification time [(3.4±1.4) minutes vs. (11.8±3.4) minutes, t=-14.07,P<0.001], shorter operation time [(155.7±44.5) minutes vs. (177.2±30.2) minutes, t=-2.48,P=0.015], less blood loss [(101.3±36.7) ml vs.(120.2±38.2) ml, t=-2.22,P=0.029], shorter distance from lesion to distal margin [(3.7±1.0) cm vs. (4.6±1.7) cm, t=-2.20, P=0.034], while tattoo group had slightly higher rate of anal sphincter preservation [66.7%(16/24) vs. 45.5%(10/22), χ(2)=2.10,P=0.234] and lower rate of first positive resection margin [0 vs. 4.5%(1/22), χ(2)=0.62,P=0.480], but their differences were not significant. There were no significant differences in the degree of tumor differentiation and TNM stage between two groups. Patients without operative indication were evaluated for efficacy of chemoradiotherapy again after half a year. One case of complete response (CR), 8 of partial response (PR), 10 of stable disease (SD) and 1 of progressive disease (PD) were found and the improvement rate was 45.0% (9/20) in tattoo-inoperable patients. No case of CR, 6 of PR, 11 of SD and 3 of PD were found and the improvement rate was 30.0% (6/20) in non-tattoo-inoperable patients. There was no significant difference in the improvement rate between the two groups (P=0.514). Conclusions: Endoscopic tattooing with carbon nanoparticles injection is safe and reliable for colorectal tumor positioning. It can assist rapid detection of lesions during surgery after neoadjuvant treatment, perform accurate resection, significantly shorten the operation time and reduce surgical trauma; can assist colonoscopy accurately to measure the size of the lesions before and after chemoradiotherapy, and increase the means of assessing the efficacy to guide the follow-up treatment plan. This technique is worth clinical promotion and application.


Assuntos
Carbono/administração & dosagem , Neoplasias do Colo/terapia , Nanopartículas/administração & dosagem , Neoplasias Retais/terapia , Tatuagem/métodos , Adolescente , Quimiorradioterapia Adjuvante , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Colonoscopia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/terapia , Terapia Combinada , Humanos , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
7.
Chem Commun (Camb) ; 56(7): 1093-1096, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31894764

RESUMO

We prepared novel conjugated polymer based NIR-II nanoparticles, which display extremely high photothermal conversion efficiency (65%). Both in vitro and in vivo investigations revealed that the as-prepared nanoparticles exhibit excellent theranostic properties including an extremely high cancer cell killing ability, admirable tumor elimination efficiency (100%) and a remarkable photoacoustic imaging contrast enhancing ability.


Assuntos
Antineoplásicos/uso terapêutico , Nanopartículas/uso terapêutico , Compostos de Organossilício/uso terapêutico , Polímeros/uso terapêutico , Tiadiazóis/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/efeitos da radiação , Células Hep G2 , Humanos , Hipertermia Induzida/métodos , Raios Infravermelhos , Camundongos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Nanopartículas/química , Nanopartículas/efeitos da radiação , Compostos de Organossilício/química , Compostos de Organossilício/efeitos da radiação , Técnicas Fotoacústicas/métodos , Polímeros/química , Polímeros/efeitos da radiação , Nanomedicina Teranóstica/métodos , Tiadiazóis/química , Tiadiazóis/efeitos da radiação
8.
Top Curr Chem (Cham) ; 378(1): 12, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31907672

RESUMO

Nanomaterials have revolutionized the sensing and biosensing fields, with the development of more sensitive and selective devices for multiple applications. Gold, silver and iron oxide nanoparticles have played a particularly major role in this development. In this review, we provide a general overview of the synthesis and characteristics of gold, silver and iron oxide nanoparticles, along with the main strategies for their surface functionalization with ligands and biomolecules. Finally, different architectures suitable for electrochemical applications are reviewed, as well as their main fabrication procedures. We conclude with some considerations from the authors' perspective regarding the promising use of these materials and the challenges to be faced in the near future.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Compostos Férricos/síntese química , Ouro/química , Nanopartículas/química , Prata/química , Compostos Férricos/química , Ligantes , Propriedades de Superfície
9.
J Environ Manage ; 258: 110038, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929071

RESUMO

Heavy metals are classified as persistent pollutants owing to their nature of bioaccumulation and affect human life and environment, even in minor concentrations. Divalent Cadmium (Cd2+) is one of the heavy metal pollutants that are highly toxic. The present study investigates the novel application of maghemite nanoparticles coated Bacillus subtilis for the removal of Cd2+ ions from its aqueous solution by batch adsorption studies. Surface characterization of the biosorbent done by Scanning Electron Microscope (SEM) and the presence of maghemite nanoparticle coat was confirmed. Parameters like pH, initial metal ion concentration, contact time, and temperature that affect the biosorption of cadmium ions are analyzed, and the equilibrium adsorption capacity expressed as a function of each of the parameters. The mechanism of biosorption was studied by plotting adsorption isotherms, and it follows pseudo-second-order kinetics. Thermodynamic studies showed the process to be spontaneous and endothermic. At optimum conditions of pH 4, 30 °C, 120 rpm, maximum removal percentage of 83.5%, which accounts for an equilibrium adsorption capacity of 32.6 mg/g of biosorbent. There was a recovery of 76.4% of the biosorbent after adsorption studies. Based on the adsorptive capacity and good recovery of the biosorbent, maghemite coated Bacillus subtilis proves to be an efficient adsorbent for the removal of Cd2+ ions from its aqueous solution.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Adsorção , Bactérias , Cádmio , Compostos Férricos , Concentração de Íons de Hidrogênio , Cinética , Temperatura Ambiente , Termodinâmica
10.
World J Microbiol Biotechnol ; 36(2): 25, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980951

RESUMO

In a search for novel therapeutic agents against pathogenic fungal species, Candida in addition to bacterial species, novel spinel nanoferrites were assayed against four pathogenic fungi isolated from different clinical samples of ear and skin infections: Aspergillus flavus, A. niger, A. terrus and A. fumigatus, four Candia species: Candida albicans, C. parapsilosis, C. krusei and C. tropicales, and four bacterial species: two Gram +ve: Bacillus subtilis and Streptococcus pyogenes, and two Gram -ve: Pseudomonas vulgaris and Escherichia coli. It was found that the assayed compounds displayed different levels of antifungal and antibacterial activities against all tested microorganisms. The antimicrobial potency depends on the method of synthesis of the nanoparticles and also on the microbial species.


Assuntos
Antibacterianos/síntese química , Antifúngicos/síntese química , Compostos Férricos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Compostos Férricos/química , Compostos Férricos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanopartículas , Relação Estrutura-Atividade
13.
Chem Commun (Camb) ; 56(8): 1255-1258, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31898700

RESUMO

Here we demonstrated that the stiffness of cationized gelatin nanoparticles determined the efficiency of RNAi in myeloid leukemia cells when the particle size and surface charges were kept constant. The siRNA delivery system with an elastic modulus of 0.87 MPa showed the largest siRNA uptake and RNAi efficiency for hard-to-transfect suspension cells.


Assuntos
Gelatina/química , Leucemia Mieloide/patologia , Nanopartículas/química , Interferência de RNA , Cátions/química , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Humanos , Células K562 , Leucemia Mieloide/tratamento farmacológico , Tamanho da Partícula , RNA Interferente Pequeno/química , RNA Interferente Pequeno/farmacologia , Propriedades de Superfície
14.
J Agric Food Chem ; 68(5): 1405-1418, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31940190

RESUMO

The aim of this study was to develop a novel system for the co-delivery of resveratrol and coenzyme Q10 (CoQ10). It was achieved with a combination of resveratrol-loaded composite nanoparticles and CoQ10-loaded Pickering emulsions. Different levels of resveratrol (0.05-0.30%, w/v) were entrapped into composite nanoparticles by the method of emulsification-evaporation. The size of composite nanoparticles was around 300-600 nm, and the maximum loading capacity of resveratrol was up to 13.88% (w/w). Hydrogen bonds, hydrophobic effects, and electrostatic attraction participated in the self-assembly of composite nanoparticles. The stability of CoQ10 Pickering emulsions was monitored under simulated environmental stresses (pH, ionic strength, UV radiation, and heat) and accelerated storage conditions. The physical stability of Pickering emulsions was dependent on the particle compositions, and the CoQ10 entrapped was also protected by the resveratrol-loaded nanoparticles. The morphology of Pickering emulsions was observed with the aid of optical microscopy, confocal laser scanning microscopy, and cryo-scanning electronic microscopy. The nutraceutical Pickering emulsions were designed for the co-delivery of resveratrol and CoQ10, which has the potential to be a novel vehicle for bioactive ingredients.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Resveratrol/química , Ubiquinona/análogos & derivados , Estabilidade de Medicamentos , Emulsões/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Concentração Osmolar , Tamanho da Partícula , Ubiquinona/química
15.
J Nanobiotechnology ; 18(1): 13, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941501

RESUMO

BACKGROUND: During the past few decades, drug delivery system (DDS) has attracted many interests because it could enhance the therapeutic effects of drugs and reduce their side effects. The advent of nanotechnology has promoted the development of nanosized DDSs, which could promote drug cellular uptake as well as prolong the half-life in blood circulation. Novel polymer micelles formed by self-assembly of amphiphilic polymers in aqueous solution have emerged as meaningful nanosystems for controlled drug release due to the reversible destabilization of hydrophobic domains under different conditions. RESULTS: The amphiphilic polymers presented here were composed of cholesterol groups end capped and poly (poly (ethylene glycol) methyl ether methacrylate) (poly (OEGMA)) as tailed segments by the synthesis of cholesterol-based initiator, followed by atom transfer radical polymerization (ATRP) with OEGMA monomer. FT-IR and NMR confirmed the successfully synthesis of products including initiator and polymers as well as the Mw of the polymers were from 33,233 to 89,088 g/mol and their corresponding PDI were from 1.25 to 1.55 by GPC. The average diameter of assembled polymer micelles was in hundreds nanometers demonstrated by DLS, AFM and SEM. The behavior of the amphiphilic polymers as micelles was investigated using pyrene probing to explore their critical micelle concentration (CMC) ranging from 2.53 × 10-4 to 4.33 × 10-4 mg/ml, decided by the balance between cholesterol and poly (OEGMA). Besides, the CMC of amphiphilic polymers, the quercetin (QC) feeding ratio and polarity of solvents determined the QC loading ratio maximized reaching 29.2% certified by UV spectrum, together with the corresponding size and stability changes by DLS and Zeta potential, and thermodynamic changes by TGA and DSC. More significantly, cholesterol end-capped polymer micelles were used as nanosized systems for controlled drug release, not only alleviated the cytotoxicity of QC from 8.6 to 49.9% live cells and also achieved the QC release in control under different conditions, such as the presence of cyclodextrin (CD) and change of pH in aqueous solution. CONCLUSIONS: The results observed in this study offered a strong foundation for the design of favorable polymer micelles as nanosized systems for controlled drug release, and the molecular weight adjustable amphiphilic polymer micelles held potential for use as controlled drug release system in practical application.


Assuntos
Colesterol/química , Portadores de Fármacos/química , Nanopartículas/química , Polietilenoglicóis/química , Animais , Linhagem Celular , Sobrevivência Celular , Ciclodextrinas/química , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Micelas , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Pirenos/química , Quercetina/administração & dosagem , Quercetina/química
16.
J Nanobiotechnology ; 18(1): 16, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959180

RESUMO

BACKGROUND: The clustered regularly interspaced short palindromic repeats (CRISPR) and Cas9 protein system is a revolutionary tool for gene therapy. Despite promising reports of the utility of CRISPR-Cas9 for in vivo gene editing, a principal problem in implementing this new process is delivery of high molecular weight DNA into cells. RESULTS: Using poly(lactic-co-glycolic acid) (PLGA), a nanoparticle carrier was designed to deliver a model CRISPR-Cas9 plasmid into primary bone marrow derived macrophages. The engineered PLGA-based carriers were approximately 160 nm and fluorescently labeled by encapsulation of the fluorophore 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene). An amine-end capped PLGA encapsulated 1.6 wt% DNA, with an encapsulation efficiency of 80%. Release studies revealed that most of the DNA was released within the first 24 h and corresponded to ~ 2-3 plasmid copies released per nanoparticle. In vitro experiments conducted with murine bone marrow derived macrophages demonstrated that after 24 h of treatment with the PLGA-encapsulated CRISPR plasmids, the majority of cells were positive for TIPS pentacene and the protein Cas9 was detectable within the cells. CONCLUSIONS: In this work, plasmids for the CRISPR-Cas9 system were encapsulated in nanoparticles comprised of PLGA and were shown to induce expression of bacterial Cas9 in murine bone marrow derived macrophages in vitro. These results suggest that this nanoparticle-based plasmid delivery method can be effective for future in vivo applications of the CRISPR-Cas9 system.


Assuntos
Proteína 9 Associada à CRISPR/genética , Sistemas CRISPR-Cas , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Proteína 9 Associada à CRISPR/metabolismo , DNA/química , Corantes Fluorescentes/química , Técnicas de Transferência de Genes , Macrófagos/metabolismo , Camundongos , Compostos de Organossilício/química , Plasmídeos , Transfecção
17.
Chem Commun (Camb) ; 56(13): 2000-2003, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31960848

RESUMO

Poor solid-tumor penetration of nanocarriers limits the drug efficacy. Herein, small-sized copolymeric nanoparticles are prepared for delivering the chemotherapeutic drug DOX into solid tumors deeply and releasing the drug effectively. These small-sized copolymeric nanoparticles represent substantial potential for clinical translation.


Assuntos
Nanopartículas/química , Polímeros/química , Animais , Sobrevivência Celular , Doxorrubicina/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Células HeLa , Humanos , Camundongos , Camundongos Nus , Microscopia Confocal , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Tamanho da Partícula
18.
J Agric Food Chem ; 68(4): 1051-1063, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31910005

RESUMO

Glycyrrhizic acid (GA) and GA nanofibrils (GN) have been shown to be efficient natural emulsifiers for formation and stabilization of food emulsions. In this work, the emulsion properties of GN in the presence of soy protein isolate-pectin complex nanoparticles (SPNPs) were studied to understand the impact of the nanofibril-nanoparticle interactions on emulsion stabilization. In the presence of low GN concentrations (0.1-0.5 wt %), the synergy in reducing the interfacial tension was observed due to SPNPs-GN complexation in the bulk and at the interface by hydrogen bonding, endowing the prepared emulsions with an overall smaller droplet size. However, obvious flocculation and clustering of oil droplets occurred in these emulsions (especially at 0.25 and 0.5 wt % GN), which are probably induced by a depletion mechanism. At high GN concentrations (1-2 wt %), due to the preferential adsorption, the GN mainly dominated the interface and the subsequent formation and properties of emulsions. Accordingly, the self-standing emulsion gels were obtained, showing a small droplet size with d32 of about 1.0-1.5 µm, homogeneous appearance and microstructure, and encouraging rheological properties including high gel strength, shear sensitivity, and good thixotropic recovery. This is mainly attributed to the formation of a fibrillar hydrogel network in the continuous phase as well as around the droplet surfaces.


Assuntos
Ácido Glicirrízico/química , Nanofibras/química , Nanopartículas/química , Pectinas/química , Proteínas de Soja/química , Adsorção , Emulsões/química , Géis/química , Tamanho da Partícula
19.
Anal Bioanal Chem ; 412(1): 81-91, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31953713

RESUMO

Methods for detecting mycotoxins are very important because of the great health hazards of mycotoxins. However, there is a high background and low signal-to-noise ratio in real-time sensing, and therefore it is difficult to meet the fast, accurate, and convenient requirements for control of food quality. Here we constructed a quantitative fluorescence image analysis based on multicolor upconversion nanocrystal (UCN)-encoded microspheres for detection of ochratoxin A and zearalenone. The background-free encoding image signal of UCN-doped microspheres was captured by fluorescence microscopy under near-infrared excitation, whereas the detection image signal of phycoerythrin-labeled secondary antibodies conjugated to the microspheres was captured under blue light excitation. We custom-wrote an algorithm to analyze the two images for the same sample in 10 s, and only the gray value in the red channel of the secondary probe confirmed the quantity. The results showed that this novel detection platform performed feasible and reliable fluorescence image measurements by this method. Additionally, the limit of detection of was 0.34721 ng/mL for ochratoxin A and 0.41162 ng/mL for zearalenone. We envision that this UCN encoding strategy will be usefully applied for fast, accurate, and convenient testing of multiple food contaminants to ensure the safety of the food.


Assuntos
Microesferas , Ocratoxinas/análise , Zearalenona/análise , Contaminação de Alimentos/análise , Imunoensaio/métodos , Limite de Detecção , Nanopartículas/química , Razão Sinal-Ruído
20.
HNO ; 68(2): 111-114, 2020 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-31996935

RESUMO

Until recently, exosomes were considered to be dust in electron microscopy. This perception has changed dramatically in the past few years. A new research field has emerged aiming to describe the formation, release, and function of these nanoparticles. The role of exosomes evolved from garbage bins to biologically active, selectively secreted particles that are part of a novel and broader messaging system. They were shown to display immunomodulatory properties. Today, exosomes are regarded as attractive targets for diagnostic and therapeutic purposes, especially in the field of oncology.


Assuntos
Exossomos , Nanopartículas , Microscopia Eletrônica
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