Cellulose acetate fibres loaded with daptomycin for metal implant coatings

Multifunctional polymeric coatings containing drug delivery vehicles can play a key role in preventing/reducing biofilm formation on implant surfaces. Their requirements are biocompatibility, good adhesion, and controllable drug release. Although cellulose acetate (CA) films and membranes are widely studied for scaffolding, their applications as a protective coating and drug delivery vehicle for metal implants are scarce. The reason is that adhesion to stainless steel (SS) substrates is non-trivial. Grinding SS substrates enhances the adhesion of dip-coated CA films while the adhesion of electrospun CA membranes is improved by an electrosprayed chitosan intermediate layer. PMMA microcapsules containing daptomycin have been successfully incorporated into CA films and fibres. The released drug concentration of 3 × 10−3 mg/mL after 120 min was confirmed from the peak luminescence intensity under UV radiation of simulated body fluid (SBF) after immersion of the fibres.This work was mainly funded by ERC-CoG-2014, CapTherPV, 647596, and partially by H2020-ICT-2014-1, RIA, TransFlexTeg, 645241 and FEDER funds through the COMPETE 2020 Program and National Funds through FCT – Portuguese Foundation for Science and Technology under the projects UIDB/50025/2020-2023 (CENIMAT/I3N), UIDP/04138/2020 and UIDB/04138/2020 (iMed.ULisboa), UIDB/00100/2020 and UIDP/00100/2020 (CQE), L. Gonçalves Principal Researcher grant (CEECIND/03143/2017), and J. Faria PhD grant PD/BD/143032/2018. The authors would like to thank the use of the electrospinning apparatus at the Biomaterials Laboratory from Soft and Bio-functional Materials Group (CENIMAT/I3N).