Ceragenin-CSA13 loaded high strength coatings of nano- and micro-SrHA implanted N-Carboxymethyl chitosan – Polyetheretherketone by low temperature high speed collision approach: In vitro pro-osteogenicity and bactericidal activity against MRSA

Cationic steroid antimicrobials (CSA13) loaded in the uniform coatings synthesized by micro and nano sized particles of strontium substituted hydroxyapatite implanted into the surface of N-carboxymethyl chitosan (N-CMCh) pre-embedded on polyetheretherketone (PEEK) substrate and their biocompatibility and antibacterial efficacy were investigated. Release of CSA13 from the nano SrHA implanted substrate showed faster release of the drug till 48 h with a release of 48% of total drug. It was found that CSA13 rich nano SrHA implanted substrate damaged the Methicillin Resistant Staphylococcus Aureus biofilm mass in 30 h, while micron sized SrHA implanted substrate reduced the biofilm mass to 27% at the same culture period. MG63 cell viability on these specimens exhibited significant cell growth even in the presence of CSA13. Nano SrHA implanted substrate showed better biocompatibility simultaneously providing antibacterial efficacy than the micro sized coating. The sustained release of CSA13 from the nano Sr-HA coating could be beneficial for long term eradication of infection. In silico docking approach between CSA13 and 1VQQ penicillin binding protein 2a from MRSA strain showed strong negative binding energy of (−) 68.78 kcal/mol demonstrating an in-visual predicting anti-bacterial efficacy.