Plasma-Deposited Nanocapsules Containing Coatings for Drug Delivery Applications

Abstract

Coatings consisting in gentamicin-containing nanocapsules have been synthetized by means of an aerosol-assisted atmospheric pressure plasma deposition process. The influence of different parameters affecting the process has been extensively investigated by means of a morphological and chemical characterization of the coatings. Scanning electron microscopy highlighted the presence of nanocapsules whose size and abundance depend on power input and deposition time. A detailed analysis carried out with matrix-assisted laser desorption ionization coupled to high-resolution mass spectrometry allowed to detect and identify the presence of gentamicin embedded in the coatings and its rearrangement, as a result of the interaction with the plasma. The release of gentamicin in water has been monitored by means of UV-vis fluorescence spectroscopy, and its biological activity has been evaluated as well by the disk diffusion assay against Staphylococcus aureus and Pseudomonas aeruginosa. It is confirmed that the antibacterial activity of gentamicin is preserved in the plasma-deposited coatings. Preliminary cytocompatibility investigations indicated that eukaryotic cells well tolerate the release of gentamicin from the coatings.

On the formation of nanocapsules in aerosol‐assisted atmospheric‐pressure plasma

“…By means of EDS, it was possible to measure the atomic composition of the composite coating before and after 1‐hr immersion in water: The atomic percent of Cu decreased from 0.4% to 0.2% together with that of sulfur, from 0.3% to 0.1%, and of oxygen, from 31.7% to 28.5%, while the atomic C percentage increased from 67.7% to 71.2%. This confirm the release in water, as shown for vancomycin and gentamicin containing coatings, of the content of the nanocapsules core.…”

“…Samples were deposited in the previously described DBD reactor, coupling the atomization of an aqueous solution (Milli‐Q quality water; Millipore, Bedford, MA) containing the mentioned different solutes by 5 slm of He (99.999%; Air Liquide), with the addition of 20 sccm of C 2 H 4 (99.95%; Air Liquide).…”

“…In previous works, we have demonstrated the possibility to prepare composite coatings with ethylene as a precursor of the matrix and He as a carrier gas for the aerosol of an aqueous 10 mM solution of vancomycin or gentamicin a.…”

Recent Advancements in the Use of Aerosol-Assisted Atmospheric Pressure Plasma Deposition

“…In particular, for Ib, the dispersion of nanoparticles (NPs) in monomers has been reported: TiO 2 /organosilicon [50,60], AlCeO 3 /HMDSO/ethanol [45], ZnO octane [57], polyhedral oligomeric silsesquioxane (POSS)/HMDSO [76]. In case II, a gaseous monomer is often inlet, as ethylene, with an aerosol in an aqueous solution of vancomycin [63,73,74], gentamicin [72] or lysozyme [59]; on the other hand, the monomer can be inlet by means of a bubbling system, as reported for the deposition of Ag NPs containing films [62], or silica layers entrapping TiO 2 NPs [61]. The additive can be a compound soluble in the aerosol liquid feed, but it can consist of both organic (e.g., polymer nanopowder) or inorganic (metals or metal oxides) nanoparticles.…”

Plasma and Aerosols: Challenges, Opportunities and Perspectives

“…This includes, for example, pristine or drug-coated nanoparticle generation and delivery to patients for nanomedicine applications (e.g., wound healing and cancer treatment) and size-controlled nanoparticles for volume catalytic processes. Alternatively, the encapsulation of biomolecules, drugs, and nanocarriers in liquid droplets seems to prevent possible plasma-induced damage during the deposition of bioactive, nanostructured and functional coatings, allowing the retention in the deposited coating of important chemical functionalities [23][24][25][26].…”