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1.
Nanomaterials (Basel) ; 9(11)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683686

RESUMO

AgNPs have attracted considerable attention in many applications including industrial use, and their antibacterial properties have been widely investigated. Due to the green synthesis process employed, the nanoparticle surface can be coated with molecules with biologically important characteristics. It has been reported that increased use of nanoparticles elevates the risk of their release into the environment. However, little is known about the behaviour of AgNPs in the eco-environment. In this study, the effect of green synthesized AgNPs on germinated plants of maize was examined. The effects on germination, basic growth and physiological parameters of the plants were monitored. Moreover, the effect of AgNPs was compared with that of Ag(I) ions in the form of AgNO3 solution. It was found that the growth inhibition of the above-ground parts of plants was about 40%, and AgNPs exhibited a significant effect on photosynthetic pigments. Significant differences in the following parameters were observed: weights of the caryopses and fresh weight (FW) of primary roots after 96 h of exposure to Ag(I) ions and AgNPs compared to the control and between Ag compounds. In addition, the coefficient of velocity of germination (CVG) between the control and the AgNPs varied and that between the Ag(I) ions and AgNPs was also different. Phytotoxicity was proved in the following sequence: control < AgNPs < Ag(I) ions.

2.
J Nanosci Nanotechnol ; 19(5): 2483-2488, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30501743

RESUMO

Modern anticancer therapy aims to increase the effectiveness of tumor treatment. The aim of this work was to propose a new nanotransporter for targeted delivery of anthracycline antibiotics, which is characterized by its bioavailability, increased uptake of the drug from the bloodstream at the site of the tumor tissue as well as low toxicity to non-target tissue. Chitosan nanoparticles have attracted great attention in the field of drug delivery due to their stability, low toxicity and easy preparation. Deacetylated chitosan skeleton is composed of glucosamine units and has a high density of charged amino groups which allow strong electrostatic interactions with biomolecules, transition metals (Zn, Se) and peptides. We obtained an effective level of chitosan encapsulation, 20%. Electrochemical detection of the bounded Zn2+ ions into the chitosan structure showed a potential shift from -0.99 to -0.93 V. This result proved the formation of a chitosan-zinc complex. The ability of metallothione to quench the 2,2-diphenyl-1-picrylhydrazyl radical in the presence of 50 µM doxorubicin was confirmed by the change of relative absorbance over the range from 50 to 60%.


Assuntos
Antineoplásicos , Quitosana , Nanopartículas , Preparações Farmacêuticas , Antibióticos Antineoplásicos , Doxorrubicina/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Zinco
3.
J Nanosci Nanotechnol ; 19(5): 2762-2769, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30501777

RESUMO

Silver nanoparticles are the most important nanoparticles in connection with the antimicrobial effect. Nowadays, the green synthesis of various types of nanoparticles is rapid, effective and produce less toxic nanoparticles often with specific properties. In our experiment we have developed and described in details various types of silver nanoparticles synthesized chemically or by the green synthesis. Nine different silver nanoparticles were synthesized, three by citrate method at different pHs (8; 9; 10), four using gallic acid at alkaline pHs (10; 11), and two by green synthesis using green tea and coffee extracts, both at pH 9. Characterisation of silver nanoparticles was performed using dynamic light scattering, scanning electron microscopy, and ultraviolet-visible absorption spectroscopy. Silver nanoparticles prepared by green synthesis showed the highest antioxidant activity and also ability for quenching of free radicals. Antibacterial activity of silver nanoparticles was determined on bacterial cultures such as Staphylococcus aureus and Escherichia coli. Silver nanoparticles synthesized using green tea and coffee extracts showed the highest antibacterial activity for both bacterial strains. Minimal inhibition concentration for both strains was found to be 65 µM at each silver nanoparticle synthesized using green synthesis.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Química Verde , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata/farmacologia
4.
Int J Mol Sci ; 19(12)2018 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-30467297

RESUMO

BACKGROUND: Sarcosine is an amino acid that is formed by methylation of glycine and is present in trace amounts in the body. Increased sarcosine concentrations in blood plasma and urine are manifested in sarcosinemia and in some other diseases such as prostate cancer. For this purpose, sarcosine detection using the nanomedicine approach was proposed. In this study, we have prepared superparamagnetic iron oxide nanoparticles (SPIONs) with different modified surface area. Nanoparticles (NPs) were modified by chitosan (CS), and sarcosine oxidase (SOX). SPIONs without any modification were taken as controls. Methods and Results: The obtained NPs were characterized by physicochemical methods. The size of the NPs determined by the dynamic light scattering method was as follows: SPIONs/Au/NPs (100⁻300 nm), SPIONs/Au/CS/NPs (300⁻700 nm), and SPIONs/Au/CS/SOX/NPs (600⁻1500 nm). The amount of CS deposited on the NP surface was found to be 48 mg/mL for SPIONs/Au/CS/NPs and 39 mg/mL for SPIONs/Au/CS/SOX/NPs, and repeatability varied around 10%. Pseudo-peroxidase activity of NPs was verified using sarcosine, horseradish peroxidase (HRP) and 3,3',5,5'-tetramethylbenzidine (TMB) as a substrate. For TMB, all NPs tested evinced substantial pseudo-peroxidase activity at 650 nm. The concentration of SPIONs/Au/CS/SOX/NPs in the reaction mixture was optimized to 0⁻40 mg/mL. Trinder reaction for sarcosine detection was set up at 510 nm at an optimal reaction temperature of 37 °C and pH 8.0. The course of the reaction was linear for 150 min. The smallest amount of NPs that was able to detect sarcosine was 0.2 mg/well (200 µL of total volume) with the linear dependence y = 0.0011x - 0.0001 and the correlation coefficient r = 0.9992, relative standard deviation (RSD) 6.35%, limit of detection (LOD) 5 µM. The suggested method was further validated for artificial urine analysis (r = 0.99, RSD 21.35%, LOD 18 µM). The calculation between the detected and applied concentrations showed a high correlation coefficient (r = 0.99). NPs were tested for toxicity and no significant growth inhibition was observed in any model system (S. cerevisiae, S. aureus, E. coli). The hemolytic activity of the prepared NPs was similar to that of the phosphate buffered saline (PBS) control. The reaction system was further tested on real urine specimens. Conclusion: The proposed detection system allows the analysis of sarcosine at micromolar concentrations and to monitor changes in its levels as a potential prostate cancer marker. The whole system is suitable for low-cost miniaturization and point-of-care testing technology and diagnostic systems. This system is simple, inexpensive, and convenient for screening tests and telemedicine applications.


Assuntos
Biomarcadores Tumorais/urina , Quitosana/química , Nanopartículas de Magnetita/química , Neoplasias da Próstata/diagnóstico , Sarcosina Oxidase/química , Sarcosina/urina , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Compostos Férricos/química , Ouro/química , Hemólise/efeitos dos fármacos , Peroxidase do Rábano Silvestre/química , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Nanopartículas de Magnetita/ultraestrutura , Masculino , Oxirredução , Tamanho da Partícula , Medicina de Precisão , Neoplasias da Próstata/urina , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
5.
Nanomaterials (Basel) ; 7(12)2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29292780

RESUMO

This work investigated the preparation of chitosan nanoparticles used as carriers for doxorubicin for targeted cancer delivery. Prepared nanocarriers were stabilized and functionalized via zinc ions incorporated into the chitosan nanoparticle backbone. We took the advantage of high expression of sarcosine in the prostate cancer cells. The prostate cancer targeting was mediated by the AntiSar antibodies decorated surface of the nanocage. Formation of the chitosan nanoparticles was determined using a ninhydrin assay and differential pulse voltammetry. Obtained results showed the strong effect of tripolyphosphine on the nanoparticle formation. The zinc ions affected strong chitosan backbone coiling both in inner and outer chitosan nanoparticle structure. Zinc electrochemical signal depended on the level of the complex formation and the potential shift from -960 to -950 mV. Formed complex is suitable for doxorubicin delivery. It was observed the 20% entrapment efficiency of doxorubicin and strong dependence of drug release after 120 min in the blood environment. The functionality of the designed nanotransporter was proven. The purposed determination showed linear dependence in the concentration range of Anti-sarcosine IgG labeled gold nanoparticles from 0 to 1000 µg/mL and the regression equation was found to be y = 3.8x - 66.7 and R² = 0.99. Performed ELISA confirmed the ability of Anti-sarcosine IgG labeled chitosan nanoparticles with loaded doxorubicin to bind to the sarcosine molecule. Observed hemolytic activity of the nanotransporter was 40%. Inhibition activity of our proposed nanotransporter was evaluated to be 0% on the experimental model of S. cerevisiae. Anti-sarcosine IgG labeled chitosan nanoparticles, with loaded doxorubicin stabilized by Zn ions, are a perspective type of nanocarrier for targeted drug therapy managed by specific interaction with sarcosine and metallothionein for prostate cancer.

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