Chitosan nanoparticles and povidone iodine containing alginate gel for prevention and treatment of orthopedic implant associated infections.

Orthopedic Implant associated infections (OIAIs) are the most serious complications in the orthopedic surgery. Such complications are of major concern unless encountered during initial stages of contamination due to the bacterial biofilm formation. Thus, our aim is to eradicate bacteria at the early stages of infection. Herein, we develop a vancomycin-loaded chitosan nanoparticles (CNPs) and povidone-iodine (PI) containing in situ alginate (CNPs-PI-Alg) gel for antibacterial and antibiofilm activity, respectively. The CNPs were synthesized by ionic gelation method and the processing parameters were optimized to attain nanoparticles of 200-250 nm size and 37.13 ± 3.18 mV charge. A PI-loaded in situ alginate (PI-Alg) gel served as a carrier wherein, the CNPs were incorporated to attain sustained release of an antibacterial agent. The CNPs-PI-Alg gel showed more stability and mechanical properties compared to the Blank-Alg gel. The CNPs-PI-Alg gel exhibited sustained release of vancomycin and PI over a period of 10-15 days. The hemolysis and cytocompatibility studies demonstrated the safety and biocompatibility of CNPs-PI-Alg gel. Furthermore, significant antibacterial and antibiofilm effect against Staphylococcus aureus showed that the CNPs-PI-Alg in situ gel has a potential for the prevention of OIAIs.