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Antibacterial activity and good mechanical properties are some of the characteristics required for an appropriate film dressing. A novel polymer blend was developed for wound healing application. Twenty-four formulations using the polymers chitosan, poly(vinyl alcohol) and/or ɛ-Polylysine and the plasticizer glycerol were designed using factorial design and then the films were prepared by the casting/solvent evaporation method. Seventeen films were obtained among the twenty-four proposed formulations that were characterized by Field Emission Scanning Electron Microscopy (FE-SEM) and Fourier Transform Infrared Spectroscopy (FTIR). Mechanical properties, such as tensile strength (σ), elongation at break (ɛ) and Young's modulus (Y) as well as antibacterial properties were determined. The best candidate was then further analyzed with regard to porosity, Water Vapor Transmission Rate (WVTR), swelling and cytotoxicity experiments. The results showed a film with semi-occlusive characteristics, good mechanical properties and no toxic. Incorporation of ɛ-Polylysine increased antibacterial activity against gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacteria.

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This work reports a new application for a well-known medicinal plant used in Brazil. The green synthesis of silver nanoparticles (AgNPs) using the aqueous extract of Monteverdia ilicifolia (MI) leaves as stabilizing and reducing agent is described. The AgNPs-MI obtained were characterized by UV-VIS, FTIR, and Raman spectroscopies, DLS, zeta potential and FEG-SEM, which demonstrated that M. ilicifolia was effective at capping the AgNPs, yielding stable suspensions. These nanoparticles were deposited on glassy carbon electrodes, and they were efficiently applied as electrochemical sensors for the determination of dopamine (DA) using square wave voltammetry (SWV). The AgNPs-MI improved the electrochemical properties of the electrodes and enhanced their electroanalytical performance. The developed sensing device presented detection and quantification limits equal to 0.52 and 1.74 ?mol�L�1, respectively, towards DA determination. The proposed electrochemical sensor quantified this neurotransmitter successfully, confirming its potential as a new promising analytical detection tool for DA quality control.