A Sensor for Monitoring the Corrosion Behavior of Orthopedic Drug Calcium Hydrogen Phosphate on a Surgical 316L Stainless Steel Alloy as Implant

Firstly, the electrochemical behavior of 316L stainless steel alloy (316L SS) as a bone implant has been studied in Hanks’ solution (pH 7.4) at 37 °C without and/or with calcium hydrogen phosphate drug of different concentrations (1 × 10−5–1 × 10−3 M). This drug acts as an inhibitor to protect the surface of the alloy from the surrounding corrosive physiological medium. The results illustrate that 1 × 10−3 M concentration of the drug is the most protective to 316L SS bone implant. Secondly, a novel sensor was developed electrochemically to sense the corrosion behavior of 316L SS in Hanks’ solution containing various concentrations of calcium hydrogen phosphate drug, by sensing the drug concentration in the solution. The sensor was built up from carbon paste modified with chitosan, cellulose acetate phthalate, and silver nanoparticles. The ACCMCPE sensor senses well the drug and exhibits a fast (1.5 s) and a stable response over different concentration ranges (1 × 10−5–1 × 10−3 M) at 50 mV/s. The techniques utilized to explore the corrosion behavior and electrocatalytic activity of the sensor are electrochemical impendence spectroscopy, potentiodynamic polarization, cyclic voltammetry, differential pulse voltammetry, and chronoamperometry. The results was confirmed well with morphological studies.