ANGELICA TAMIÃO ZAFALON

Projetos de Pesquisa
Unidades Organizacionais
Cargo

Resultados de Busca

Agora exibindo 1 - 4 de 4
  • Resumo IPEN-doc 27604
    Development of poly (n-vinyl-2-pyrrolidone) hydrogels containing nanosilver and laponite clay for modulation of neomycin
    2020 - PARRA, DUCLERC F.; SANTOS, VINICIUS J. dos; TAMIÃO, ANGELICA
    These Biomaterials widely used in biomedicine as wound dressings are composed by hydrogels. They offer ideal conditions for wound treatment, such as maintaining the wound environment humid, autolytic debridement, accelerated healing, ability to absorb large amounts of fluids without losing their physical integrity, drug release in a controlled manner protecting infected wounds that are constantly exposed to environment contaminated with microorganisms. These dressings are formed by one or more polymeric components which, when cross-linked, form three-dimensional networks. They have a high degree of flexibility that is very similar to natural living tissues. The general objective of this work was to synthesize by radiation hydrogel membranes containing PVP, PEG, agar, RD laponite in a neomycin and nanosilver release system that promotes a synergistic action between these two antimicrobial agents. Membranes with different concentrations of polymer matrix / clay were produced by irradiation at a dose of 25 kGy of gamma 60Co source, and characterized by techniques: swelling analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), tensile tests, parallel plate rheometry. It can be seen that G 'and G "are approximately parallel within the studied range. G 'is greater than G' 'and both showed little frequency dependence. This performance is the expected for the gels, in which the elastic behavior of the sample predominates over its viscous behavior. The clay-polymer interactions increases gel cross-linking, which provides an increase in their mechanical properties. In parallel, nanoparticles of silver coupled to clay (Laponite) were synthesized in which their properties were verified by means of UV-Vis, MET, ICP-OES and microbiological activity. The study of the microbiological activity of AgNPs-Laponite nanoparticles on the reduction of microorganisms in culture indicated that most of the nanoparticles, synthesized from the reduction of silver ions on the surface of Laponite, have activity against Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Candida albicans.
  • Capítulo IPEN-doc 25620
    Synthesis and characterization of PVP/CaCO3-Ag blend hydrogel by gamma irradiation
    2019 - ZAFALON, ANGELICA T.; JUVINO, VINICIUS dos S.; KOMATSU, LUIZ G.H.; PARRA, DUCLERC F.; LUGAO, ADEMAR; SAMUEL, TEMESGEN; RANGARI, VIJAYA
    Chronic wounds are skin injuries with failed healing. They have become a public health problem that affects more than 2% of the population and the presence of bacteria resistances difficult of treatment. Pseudomonas aeruginosa is opportunist pathogens and the treatment is difficult and requires a long period of treatment. Hydrogels are structure polymeric tridimensional and biocompatible. They have been used as a controlled delivery system for treatment of topic infection. Studies have reported calcium carbonate and silver ion can improve the mechanical properties and biocide activity of hydrogel. Here in this study, hydrogels loaded CaCO3-Ag were prepared using poly (N-vinyl-2-pyrrolidone), poly (ethylene glycol), agar, calcium carbonate, silver nitrate followed gamma irradiation with 25 kGy dose. The gel fraction, behavior swelling and biocide action against P. aeruginosawas investigated. The degree of swelling of the hydrogel loaded CaCO3-Ag was 12% higher than the unloaded and exhibited antibacterial effects against P. aeruginosa and biofilm.
  • Capítulo IPEN-doc 24657
    Synthesis of polymeric hydrogel loaded with antibiotic drug for wound healing applications
    2018 - ZAFALON, ANGELICA T.; SANTOS, VINICIUS J. dos; ESPOSITO, FERNANDA; LINCOPAN, NILTON; RANGARI, VIJAYA; LUGAO, ADEMAR B.; PARRA, DUCLERC F.
    Polymeric hydrogels are natural or synthetic systems, which have gained interest due to their high biocompatibility with soft tissues. These types of hydrogels have been used for wound dressing as a drug delivery system. Here in this study the polymeric hydrogels based wound healing systems were prepared using poly (N-vinyl-2-pyrrolidone) (PVP), poly (ethylene glycol) (PEG), agar and neomycin drug followed by gamma irradiation to promote crosslinking and sterilization. The influence of irradiation process with 25 kGy dose was investigated. The gel fraction and maximum swelling were estimated using physicochemical methods and found about 95% gel fraction and 1100% swelling after 8 h of immersion. Neomycin released from hydrogel was carried out by Liquid Chromatography-Mass Spectrometry method and the drug concentration remained constant for 48 h. Hydrogel/neomycin exhibited antibacterial effects against Staphylococcus aureus. With these results, it can be inferred that hydrogel/neomycin is a suitable candidate for wound dressing.
  • Artigo IPEN-doc 21022
    Gamma radiation use for hydrogels of poly(N-vinyl 2-pyrrolidone) containing nanoclay laponite
    2015 - SANTOS, VINICIUS J. dos; TAVARES, ANGELICA T.; LUGAO, ADEMAR B.; RANGARI, VIJAYA K.; PARRA, DUCLERC F.