Silver nanoparticle-coated orthopedic screws lead to greater calcium precipitation

Orthopedic implants are commonly used for treating major bone injuries and offer enormous benefits to the healing process. However, these implants can face issues such as patient rejection, infection, and a lack of integration into surrounding bone which could lead to inflammation and implant loosening. To overcome these limitations, we hypothesized that stainless steel orthopedic screws coated with environmentally friendly silver nanoparticles would enhance acellular calcium precipitation, thus promoting the integration of the implant into surrounding bone. We synthesized environmentally friendly silver nanoparticles then coated stainless steel orthopedic screws with the 633 nm silver nanoparticles. Afterwards, we placed the screws into a calcium solution that models the soluble calcium surrounding an implant in the body. We observed that screws coated with silver nanoparticles and uncoated screws visibly accumulated calcium when left in the beaker overnight, as demonstrated by scanning electron microscopy (SEM). This indicates that if placed in the human body, prominent calcium precipitation would occur, aiding implant integration into bone. Upon further evaluation, we found that SEM images of screws after being left in the calcium solution revealed a more nanorough surface for the screws which were coated with silver nanoparticles beforehand, indicating more calcium formation. We also used energy dispersive spectroscopy (EDS) to confirm that calcium accumulated on the screw surface. In summary, this study suggests that the silver nanoparticle-coated stainless-steel screws should be further investigated for improved orthopedic implant efficacy.