33 research outputs found
Zinc-modified nanotransporter of anticancer drugs for targeted therapy: biophysical analysis.
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 tumor tissue and 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 the encapsulation effectiveness of chitosan 20%. Electrochemical detection of the bounded Zn2+ ions into the chitosan structure showed shift from -0.99 to -0.93 V. This result proved the formation of a chitosan-zinc complex. The ability of metallothione in to quench the 2,2-diphenyl-1-picrylhydrazylradicalin the presence of 50 {aelig}M doxorubicin was confirmed by the change of relative absorbance in the range of 50 to 60%
Zinc-modified nanotransporter of doxorubicine for multi-targeted therapy of prostate cancer cells.
Target therapy for oncologic diseases presents a big challenge for advance nanomedicine. In our work, we focused on multi-target approach development. Designed nanotransporter is based on polysaccharide chitosan which allows formation of nanoparticles. These nanoparticles can bind metal ions, mainly zinc (moreover, zinc stabilizes chitosan structure). The estimated zinc concentration was approximately 1 nmol/g of chitosan. In addition, chitosan nanoparticle (cage) irreversibly binds therapeutics which could be applied for targeted therapy of malignant tumours. Designed chitosan structure (LMQ, 10 g) encapsulation efficiency for doxorubicin was 50%. The pH change (tested interval 5 - 8) caused 20% release of doxorubicin from the nanocage. The nanotransporter is orientated to cancer tissue due the fact that the malignant cells highly express metallothionein (MT). The increased affinity of MT to zinc ions causes that the nanotransporter is preferentially bound to tumour regions with a high MT concentration. Our latest experimental results showed the changes in amino acid metabolism of prostate cancer signalized by increase in the amount of amino acid sarcosine. Therefore, the chitosan-based nanotransporter was modified by anti-sarcosine antibody. The functionality of designed nanotransporter was proved by ELISA with double detection of doxorubicin using fluorescence and by peroxidase activity of ABTS substrate. In another system, magnetic separation and identification of individual components of the nanotransporter were used. The sarcosine binding activity was estimated around 50%
Zinc-modified nanotransporter of doxorubicin for targeted prostate cancer delivery.
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
Phytotoxicity of silver nanoparticles (AgNPs) prepared by green synthesis using sage leaves (Salvia officinalis).
Silver nanoparticles (AgNPs) are widely investigated with regard to their physical, chemical, but also biological properties. Antibacterial and antitumor properties of AgNPs have been intensively studied. In addition, the synthesis using a green approach brings further significant biological properties. However, it is also necessary to monitor the potential toxicity of such nanoparticles in different ecosystems. In this study, the effect of AgNO3 and AgNPs on germinated plants of Zea mays was studied. Effects on basic growth and physiological parameters were observed. There was a statistically significant difference between the variants tested
A rapid method for the detection of sarcosine using SPIONs/Au/CS/SOX/NPs for prostate cancer sensing.
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
Development of new silver nanoparticles suitable for materials with antimicrobial properties.
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 {aelig}M at each silver nanoparticle synthesized using green synthesis
3D-printed CdTe QDs-based sensor for sensitive electrochemical detection of viral particles.
Preventing the spread of dangerous viral diseases such as flu, Ebola or HIV requires rapid and effective diagnostic approaches to detect these diseases at an early stage. Quantum dots (QDs) are nanocrystals that exhibit a variety of unique properties and are suitable for biomolecule labelling due to their high stability, ease of preparation, and biocompatibility. Modified QDs can be used to label nucleic acids or antibodies. Green synthesis method of QDs provides a platform for preparation of unique materials with new chemical or physical properties as compared to the original material. In this work, CdTe QDs were produced in the presence of plant extract which acted as a modifying agent. The Zea mays extract was added during the CdTe QDs synthesis at different time intervals and CdTe QDs showed a wide range of colors. The stability of the prepared QDs, including their application onto paper, was evaluated. The QDs were observed to show a remarkable electrochemical response for sensor applications and were also employed to label virus-specific antibody. The entire procedure was miniaturized and the viral particles were analyzed in a 3D-printed chip
Biophysical analysis of silver nanoparticles prepared by green synthesis and their use for 3D printing of antibacterial material for health care.
The resistance of microorganisms to antibiotics is growing steadily. The development of new antibacterial agents is highly topical. Metal nanoparticles have shown significant antibacterial activity similar to the plant/animal materials used in traditional medicine. The study focuses on the synthesis of silver nanoparticles (AgNPs) modified with biomolecules from used plant extracts (T. serpyllum, S. officinalis, T. pratense). The obtained nanoparticles were studied in detail by physicochemical methods. In addition, they were deposited on acrylonitrile butadiene styrene (ABS). We created unique antibacterial material using 3D printing. 20-40% inhibition of S. aureus and E. coli was observed in the evaluation of their efficacy
Lattice modes and the Jahn-Teller ferroelectric transition of GaV4S8
Crystal of GaV4S8, a multiferroic system hosting a Neel-type skyrmion lattice phase, has been investigated by polarized Raman and IR spectroscopy above and below the ferroelectric phase transition. Counts of the observed IR and Raman-active modes belonging to distinct irreducible representations agree quite well with group-theory predictions. Phonon spectra are assigned and interpreted with the aid of ab initio calculations of the phonon spectra in the ferroelectric phase. Results allow appreciation of phonon frequencies of the modes involved in Jahn-Teller distortion and their contribution to the spontaneous polarizationclos
An assessment of the effect of green synthesized silver nanoparticles using sage leaves (Salvia officinalis L.) on germinated plants of maize (Zea mays L.).
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