Antibacterial activity of NiTi alloy with sputtered tantalum

A study was conducted on the use of the Mactrontronic Sputtering (DC) plasma technique by sprinkling tantalum metal (Ta) and depositing it on shape-memory nickel-titanium (NiTi) alloy and glass substrates in the presence of oxygen and argon gases. As a result, a coating of tantalum oxide (Ta2O5) deposited on the (NiTi) alloy was obtained. The change of the atomization plasma energy on the size of the precipitated oxide particles (Ta2O5) and its effect on the structural properties was discussed. For the membrane, the X-ray diffraction (XRD) tests showed that the films prepared at energies of (10, 15, 25, 30, and 35 watts) showed an amorphous structure, and the (AFM) results confirmed that the thinly deposited films consisted of spherical particles. Moreover, the results of the optical properties study showed the effect of annealing (heat treatment), whereby the annealing improved all the optical parameters of the deposited films. In addition, the contact angle measurements showed that the (Ta2O5) films exhibited hydrophilic characteristics and increased wettability for the (NiTi) alloy, which normally contributes to enhancing its resistance to bacteria and facilitating cell connection. Bacterial antimicrobial assays demonstrated that the deposited membrane exhibited antibacterial activity against both negative and positive bacteria. In particular, the test results revealed that the (NiTi) alloy samples coated with (Ta2O5) membrane had a higher bacteria-killing percentage for both negative and positive bacteria compared to the uncoated samples.