Study of the effect of paracetamol binded in polymeric nanoparticles on dafnia magna.

Drugs are important xenobiotics in the environment. Their use increases with the growth of the human population, but also in agricultural primary production. Paracetamol (PAR) is a widely used analgesic and antipyretic and its production is still growing. Commonly available drug production technologies are being developed very intensively with nanotechnological modifications for their gradual and targeted release. Nanoparticles (ST/PAR) from starch were prepared: PAR (0, 1, 2, 3, 5 and 10 mg/L) was mixed with citric acid ester in a 1:8 v/v ratio for 30 min at 25 °C. By the centrifugation (16.000 g, 30 min) ST/PAR were obtained in the pellet. The effect of PAR was studied on Daphnia magna Straus (Cladocera, Crustacea). Adult females (70-400 mg) were used for self-evaluation. The EC50 was 3.749 mg/L after 48 h of PAR treatment. Total protein values determined by Lowry method were between 0.5-2.2 mg/mL and by Bradford method between 190-676 mg/L. Antioxidant activity values determined by CUPRAC method were between 4-15 μg/mL GAE and by ABTS method ranged between 40-103 μg/mL GAE. PAR values were between 9-40 μM. Subsequently, the biological activity of the prepared nanoparticles was tested

Theranostic approach for the protein corona of polysaccharide nanoparticles.

Polysaccharide nanoparticles are promising materials in the wide range of disciplines such as medicine, nutrition, food production, agriculture, material science and others. They excel- not only in their non-toxicity and biodegradability but also in their easy preparation. As well as inorganic particles, a protein corona (PC) around polysaccharide nanoparticles is formed in biofluids. Moreover, it has been considered that the overall response of the organism to nanoparticles presence depends on the PC. This review summarises scientific publications about the structural chemistry of polysaccharide nanoparticles and their impact on theranostic applications. Three strategies of implementation of the PC in theranostics have been discussed: I) Utilisation of the PC in therapy; II) How the composition of the PC is analysed for specific disease markers; III) How the formed PC can interact with the immune system and enhances the immunomodulation or immunoelimination. Thus, the findings from this review can contribute to improve the design of drug delivery systems. However, it is still necessary to elucidate the mechanisms of nano-bio interactions and discover new connections in nanoscale research

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%

Antimicrobial Nanomaterials in the Food Industry

Nanoparticles of metals interacting with cellular components and biomacromolecules including DNA and RNA alter cellular processes. Concerning the antimicrobial activity, the metal nanoparticles in nanomolar concentrations inhibit the growth of bacterial strains. Even though the general mechanism of metal nanoparticle action has not been fully understood yet, among current accepted schemes belong the damage of the microbial enzymes by the release of metal ions, the membrane integrity changes, penetration into the cytoplasm of bacteria and accumulation in the periplasmic space or the reactive oxygen species formation due to the effect of metal nanoparticles. Moreover, G+ bacteria react remarkably later on the effect of metal nanoparticles compared to G- bacteria, which is reflected in the later inhibition of cell division. The aim of this study is to describe the properties of metal nanoparticles (silver, selenium, copper or zinc nanoparticles) and to compare their antimicrobial properties in complex with chitosan on the bacterial strains Staphylococcus aureus and Escherichia coli

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

Complexes of Silver(I) Ions and Silver Phosphate Nanoparticles with Hyaluronic Acid and/or Chitosan as Promising Antimicrobial Agents for Vascular Grafts

Polymers are currently widely used to replace a variety of natural materials with respect to their favourable physical and chemical properties, and due to their economic advantage. One of the most important branches of application of polymers is the production of different products for medical use. In this case, it is necessary to face a significant disadvantage of polymer products due to possible and very common colonization of the surface by various microorganisms that can pose a potential danger to the patient. One of the possible solutions is to prepare polymer with antibacterial/antimicrobial properties that is resistant to bacterial colonization. The aim of this study was to contribute to the development of antimicrobial polymeric material ideal for covering vascular implants with subsequent use in transplant surgery. Therefore, the complexes of polymeric substances (hyaluronic acid and chitosan) with silver nitrate or silver phosphate nanoparticles were created, and their effects on gram-positive bacterial culture of Staphylococcus aureus were monitored. Stages of formation of complexes of silver nitrate and silver phosphate nanoparticles with polymeric compounds were characterized using electrochemical and spectrophotometric methods. Furthermore, the antimicrobial activity of complexes was determined using the methods of determination of growth curves and zones of inhibition. The results of this study revealed that the complex of chitosan, with silver phosphate nanoparticles, was the most suitable in order to have an antibacterial effect on bacterial culture of Staphylococcus aureus. Formation of this complex was under way at low concentrations of chitosan. The results of electrochemical determination corresponded with the results of spectrophotometric methods and verified good interaction and formation of the complex. The complex has an outstanding antibacterial effect and this effect was of several orders higher compared to other investigated complexes

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

Silver nanomaterials for wound dressing applications.

Silver nanoparticles (AgNPs) have recently become very attractive for the scientific community due to their broad spectrum of applications in the biomedical field. The main advantages of AgNPs include a simple method of synthesis, a simple way to change their morphology and high surface area to volume ratio. Much research has been carried out over the years to evaluate their possible effectivity against microbial organisms. The most important factors which influence the effectivity of AgNPs against microorganisms are the method of their preparation and the type of application. When incorporated into fabric wound dressings and other textiles, AgNPs have shown significant antibacterial activity against both Gram-positive and Gram-negative bacteria and inhibited biofilm formation. In this review, the different routes of synthesizing AgNPs with controlled size and geometry including chemical, green, irradiation and thermal synthesis, as well as the different types of application of AgNPs for wound dressings such as membrane immobilization, topical application, preparation of nanofibers and hydrogels, and the mechanism behind their antimicrobial activity, have been discussed elaborately