Melittin antimicrobial peptide thin layer on bone implant chitosan-antibiotic coatings and their bactericidal properties

Abstract

Antibiotics resistant bacteria and biofilm formation on bone implants are the main challenges of present treatment methods in hip or joint replacement surgeries. Recently, antimicrobial peptides (AMPs) have been widely evaluated to degrade resistant bacteria and biofilms. In the present study, chitosan and chitosan/antibiotic were coated on etched titanium specimens by spin coating method and then Melittin thin layer applied on coatings by casting method. Chitosan-Melittin double layer with Melittin higher than 0.2 μg/mL created bactericidal surface and eradicated MRSA bacteria. Melittin, higher than 0.2 μg/mL, showed a toxic effect on MC3T3 pre osteoblast cells. Whereas, coatings with a combination of oxacillin (0.16 μg/mL) and Melittin (0.05 μg/mL) were able to kill MRSA bacteria. Also, coatings with chitosan/vancomycin (0.16 μg/mL)-Melittin (0.05 μg/mL) were able to eradicate VRSA bacteria after 6 h. In conclusion, by the synergistic effect of antibiotics and Melittin, antibiotic-resistant bacterial infections and biofilm formation can be prevented without toxicity.