Pulsed Laser-Driven Phase Transition in Biphasic Black Titania Nanostructures for Enhanced Cancer Therapy

Abstract

An undemanding approach was employed to synthesize black titania (B-TiO2) using nanosecond rotary pulsed laser irradiation without the use of a solvent. Herein, anatase titanium dioxide (TiO2) was irradiated using a rotary nonfocused Nd:YAG laser with 1064 nm wavelength and 300 mJ pulse power, directing to B-TiO2 formation. Simultaneously, a phase change from anatase to rutile was observed at different irradiation times. Various analytical techniques were employed to assess the crystalline phases, surface strictures, band edge positions, and optical properties of the prepared B-TiO2 nanomaterials. A green model was anticipated to elucidate the ultrafast phase conversion process from anatase to rutile without solvent, considering the growth and nucleation of the rutile phase. The anticancer potential of obtained biphasic B-TiO2 was explored along with the possible molecular mechanisms underlying its induction of apoptosis in the MDA-MB-231 breast cancer cell line. These defects play a pivotal role in promoting reactive oxygen species generation, ultimately leading to DNA damage and oxidative stress within cancer cells. Therefore, it controls the Bax/bcl2/caspase signaling pathway, inhibiting the cancer cells growth and inducing apoptosis. These results provide a basis for further research focused on evaluating B-TiO2 as an efficient chemotherapeutic approach, which may eventually lead to translational studies and clinical trials aimed at completely eradicating breast cancer.