Silver Nanoparticles Biocomposite Films with Antimicrobial Activity: In Vitro and In Vivo Tests

Abstract

Overuse of antimicrobials by the population has contributed to genetic modifications in bacteria and development of antimicrobial resistance, which is very difficult to combat nowadays. To solve this problem, it is necessary to develop new systems for the administration of antimicrobial active principles. Biocomposite systems containing silver nanoparticles can be a good medical alternative. In this context, the main objective of this study was to obtain a complex system in the form of a biocomposite film with antimicrobial properties based on chitosan, poly (vinyl alcohol) and silver nanoparticles. This new system was characterized from a structural and morphological point of view. The swelling degree, the mechanical properties and the efficiency of loading and release of an anti-inflammatory drug were also evaluated. The obtained biocomposite films are biocompatibles, this having been demonstrated by in vitro tests on HDFa cell lines, and have antimicrobial activity against S. aureus. The in vivo tests, carried out on rabbit subjects, highlighted the fact that signs of reduced fibrosis were specific to the C2P4.10.Ag1-IBF film sample, demonstrated by: intense expression of TNFAIP8 factors; as an anti-apoptotic marker, MHCII that favors immune cooperation among local cells; αSMA, which marks the presence of myofibroblasts involved in approaching the interepithelial spaces for epithelialization; and reduced expression of the Cox2 indicator of inflammation, Col I.

PVA/Chitosan Thin Films Containing Silver Nanoparticles and Ibuprofen for the Treatment of Periodontal Disease

“…However, quite large amounts of AgNps could be incorporated by this method, but the use of larger amounts of AgNps (>4.16 wt.%) leads to their agglomeration. Similar results were reported by Popescu and co-workers [ 58 ] and Cadinoiu and co-workers [ 55 ], who prepared composite CS/PVA hydrogels or films by using preformed CS-capped AgNps. FT-IR/ATR spectra ( Figure 4 b) of the composite films containing AgNps show all the characteristic peaks mentioned above for pure PVA/OxCS film (F #0); the similarity in the spectra representing a sign of the proper dispersion of filler materials in the film matrix [ 83 ].…”

“…The literature data are controversial: while some researchers state that increasing the silver content in the films decreases or even does not change the hydrophilicity [ 55 , 92 ], on the contrary, others note an increase in the hydrophilicity [ 83 , 93 ]. The impact of the incorporation of silver nanoparticles on the PVA/OxCS film’s swelling behavior in time was evaluated.…”

“…Then, in the next 7 h, almost the same difference is kept, after which the curves start to flatten. The entire amount of loaded IBF was released from both samples in 72 h. A slower release rate of IBF (up to 80% in 72 h) was obtained for PVA/CS/AgNps films cross-linked with glutaraldehyde and MgSO 4 [ 55 ].…”

“…Studies have described the potential of AgNps to combat the dental biofilm reducing the prevalence of dental caries [ 50 ], periodontal disease [ 49 , 51 ], and other oral bacterial conditions [ 49 , 52 ]. The incorporation of such agents into a polymeric matrix can increase the wound healing efficacy due to their increased retention at the site of action, sustained release, and greater interaction with the wound environment [ 53 , 54 , 55 ]. The strategy of capping the AgNps can improve biocompatibility by creating a surface functionalization [ 56 ].…”

“…Chitosan has been proven to exercise positive effects on the properties of nanoparticles, and thus may contribute to better activities of silver nanoparticles. Moreover, it is expected that CS covering AgNps will not only stabilize the nanoparticles but will also assure the compatibility between the metal and the matrix in the final composite material containing PVA and CS [ 55 , 58 ]. On the other side, even if bacteria are essential agents in periodontal disease, the host’s immune–inflammatory responses play an important role in the destruction of periodontal attachment structures, so non-steroidal anti-inflammatory drugs are also used for periodontitis treatment [ 59 , 60 ].…”