Urease-Powered Black TiO₂ Micromotors for Photothermal Therapy of Bladder Cancer

Abstract

Urease-powered nano/micromotors can move at physiological urea concentrations, making them useful for biomedical applications, such as treating bladder cancer. However, their movement in biological environments is still challenging. Herein, Janus micromotors based on black TiO 2 with urease asymmetric catalytic coating were designed to take benefit of the optical properties of black TiO 2 under near-infrared light and the movement capability in simulated bladder environments (urea). The black TiO 2 microspheres were halfcoated with a thin layer of Au, and L-Cysteine was utilized to attach the urease enzyme to the Au surface using its thiol group. Biocatalytic hydrolysis of urea through urease at biologically relevant concentrations provided the driving force for micromotors. A variety of parameters, such as urea fuel concentration, viscosity, and ionic character of the environment, were used to investigate how micromotors moved in different concentrations of urea in water, PBS, NaCl, and urine. The results indicate that micromotors are propelled through ionic self-diffusiophoresis caused by urea enzymatic catalysis. Due to their low toxicity and in vitro anticancer effect, micromotors are effective agents for photothermal therapy, which can help kill bladder cancer cells. These promising results suggest that biocompatible micromotors hold great potential for improving cancer treatment and facilitating diagnosis.

Titania–Graphene Oxide Nanocomposite-Based Philadelphia-Positive Leukemia Therapy

“…Nanotechnology is a welcome option to overcome the limitations of resistance, relapse, and adverse effects and increase the plasma half-life of free TKIs. − Titanium dioxide (TiO 2 ) is Food and Drug Administration (FDA) approved and has widely been used in nano drug delivery systems for cancer, rheumatic diseases, prosthetics, tissue regeneration, and antimicrobials. − Only nanoscale TiO 2 -based leukemia therapy has also been reported by various studies. , Likewise, graphene oxide (GO) is a two-dimensional carbon nanomaterial known for higher biocompatibility due to its hydrophilic nature. GO is fabricated by the oxidation of graphite and offers a robust scaffold for drug delivery by containing hydroxyl, carboxyl, and other reactive groups on its surface for successful drug and ligand conjugation .…”