Cobalt-containing alloys are useful for orthopaedic applications due to their corrosion resistance and high mechanical strength, hardness, and fatigue resistance. Because of these properties, metal-on-metal (MoM) hip implants containing cobalt were introduced as next-generation prosthetics due to their low volumetric wear rates. Unfortunately, it was discovered after widespread implantation that these prosthetics released significant levels of cobalt ions. These cobalt ions can result in local toxic effects—including peri-implant toxicity, aseptic loosening, and pseudotumors—as well as systemic toxic effects—including neurological, cardiovascular, and endocrine disorders. Failing MoM implants usually necessitate painful, risky, costly revision surgeries. To ameliorate metallosis from MoM implants, we created a synovial fluid-mimicking chelator designed to remove these metal ions. Hyaluronic acid (HA), the major chemical component of synovial fluid, is functionalized with British anti-Lewisite (BAL) to create BAL-HA. BAL-HA effectively binds cobalt, improves the vitality by up to 370% of cells exposed to IC50 levels of cobalt in vitro, and enhances the rate (t1/2 from 48 h to 6 h) and amount (40% more cleared in 48 h) of cobalt clearance compared to control in a rat model of metallosis in vivo. This new “BioBinder” has potential to mitigate cobalt toxicity from failing MoM implants through non-invasive injections into the synovium.

Hyaluronic acid functionalized with British anti-Lewisite (dimercaprol) as a “biobinder” for safer cobalt chelation therapy to treat metallosis from metal-on-metal hip implants

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.