In this Project, we used antimicrobial peptides nanoencapsulated in mesoporous biopolymeric/magnetic nanoparticle composites materials. The nanovectors were delivered to implant surfaces as thin coatings via laser light, using a deposition technique called MAPLE (Matrix Assisted Pulsed Laser Evaporation). The deposited nanoparticle layers were thoroughly investigated by AFM (surface roughness of coatings, surface parameters, 3D surface profiles), SEM (particles shape, coalescence, diameter assessment), TEM (biopolymer crystallinity, visualization of composing layers), XRD (crystallinity of composing elements), FTIR (comparison of functional peaks from both targets and coatings spectra) and adherence tests at the substrate-nanocoating interfaces. The antimicrobial activity will be assessed on planktonic and biofilm embedded in ESKAPE Gram-negative rods pathogens. Biocompatibility and antibacterial efficiency of nanovectors will be tested in a final in vivo step on white holoxenic mice.

In this project, biopolymer-antibiotic, biopolymer-flavonoid, biopolymer-antibiotic-flavonoid composite coatings have been deposited onto assays by matrix assisted pulsed laser evaporation (MAPLE) using a pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz). FTIR spectroscopy has been used to demonstrate that MAPLE-transferred materials exhibit chemical properties similar to those of the starting materials. Atomic force microscopy has confirmed that MAPLE may be used to fabricate thin films with appropriate surface properties for medical use. The activity of flavonoid-containing films against both Gram- + and Gram- – bacteria has been examined using in vitro biological assays. The tested biological properties included the microbial viability and adherence to the flavonoid-containing films, using Gram - and Gram + bacterial strains with known antibiotic susceptibility behavior, microbial adherence to the HeLa cells monolayer grown on the of flavonoid-containing coating, and cytotoxicity on eukariotic cells.