Inhibitory effect of amlodipine and simvastatin on the degradation of a CoCrMoMnTi bio-high entropy alloy in phosphate-buffered saline

Bio high entropy alloy (Bio-HEA) is one of the many applications of high entropy alloy materials. CoCrMoMnTi Bio-HEA developed refers to the commercial CoCrMo implant material, which is widely used in orthopedic and cardiovascular. Amlodipine has beneficial effects in inhibiting neointimal hyperplasia and accelerated bone fracture healing, while simvastatin is known to improve osteoblast function and implant osseointegration. It’s important to know the effect of amlodipine and simvastatin on the implant material. The CoCrMoMnTi Bio-HEA ingots were prepared in a vacuum arc melting on a water-cooled copper mold under an argon atmosphere from the high purity of the raw material. The composition is confirmed by energy-dispersive X-ray spectroscopy. The microstructure was investigated with an optical microscope and scanning electron microscope. The corrosion parameter and inhibitory effect of amlodipine and simvastatin (5 ng/ml concentration) on CCM-MnTi occurred in PBS at 37 °C. The addition of amlodipine and simvastatin decreases the donor density up to 3.7 x 1020 cm−3 and 3.4 x 1020 cm−3 and the corrosion rate up to 0.014 and 0.005 mmpy, respectively. The amlodipine and simvastatin could act as inhibitors to the CoCrMoMnTi Bio-HEA. The inhibitory effectiveness of amlodipine is 28%, and the simvastatin is 77%.