The prominent role of fully-controlled surface co-modification procedure using titanium nanotubes and silk fibroin nanofibers in the performance enhancement of Ti6Al4V implants

Modification of orthopedic implant surfaces through advanced nanoscale coating methods has made a major breakthrough in maximizing implantation success. Adjustable drug release and biocompatibility are among the most momentous features since they can significantly prevent the implantation failure. In this study, the potential of silk fibroin (SF) nanofibers fabricated via electrospinning, along with titanium oxide nanotube arrays (TNTs) formed through anodization, were exploited to produce a cyto-biocompatible, well-controlled drug delivery system. Highly-ordered TNTs were formed in an organic electrolyte solution within 2 h at the voltage of 60 V under temperature controlling (16 degrees C). Vancomycin was loaded using a vacuum system designed for this purpose. A two-level full factorial design of experiments was carried out to obtain the highly suitable, optimized conditions to create an electrospun fibrous network with aligned uniform nanofibers, which revealed the dominant role of polymeric solution concentration in the generation of nanofibers. The topography and surface roughness results determined by atomic force microscopy (AFM), showed a considerable boost in the surface roughness of the coated samples, which resulted in enhanced cell adhesion, viability, and osseointegration, especially in the co-modified one (TNT/SF). Drug release outcomes demonstrated a conspicuous decrease in the burst release percentage (from 88% for bare to 20% for TNT/SF sample), and a noticeable overall release time extension (from 10 days for bare to 40 days for TNT/SF sample) at a near zero-order release rate caused by the surface co-modification.

Automated summary

Advanced nanoscale coating methods on orthopedic implant surfaces have significantly improved implantation success by allowing adjustable drug release and enhancing biocompatibility. The combination of silk fibroin nanofibers and titanium oxide nanotube arrays has been shown to create a well-controlled drug delivery system with excellent cell biocompatibility.