ABSTRACT
The widespread use of titanium dioxide (TiO2) has raised concerns about potential health risks associated with its cytotoxicity in the cardiovascular system. To evaluate the cytotoxicity of TiO2 particles, the H9c2 rat cardiomyoblasts were used as a biological model, and their toxicological susceptibility to TiO2-anatase and TiO2-rutile particles was studied in vitro. The study examined dose and time exposure responses. The cell viability was evaluated based on metabolic inhibition and membrane integrity loss. The results revealed that both TiO2-anatase and TiO2-rutile particles induced similar levels of cytotoxicity at the inhibition concentrations IC25 (1.4-4.4 µg/cm2) and IC50 (7.2-9.3 µg/cm2). However, at more significant concentrations, TiO2-rutile appeared to be more cytotoxic than TiO2-anatase at 24 h. The study found that the TiO2 particles induced apoptosis events, but necrosis was not observed at any of the concentrations of particles used. The study considered the effects of microstructural properties, crystalline phase, and particle size in determining the capability of TiO2 particles to induce cytotoxicity in H9c2 cardiomyoblasts. The microstress in TiO2 particles was assessed using powder X-ray diffraction through Williamson-Hall and Warren-Averbach analysis. The analysis estimated the apparent crystallite domain and microstrain of TiO2-anatase to be 29 nm (ε = 1.03%) and TiO2-rutile to be 21 nm (ε = 0.53%), respectively. Raman spectroscopy, N2 adsorption isotherms, and dynamic light scattering were used to identify the presence of pure crystalline phases (>99.9%), comparative surface areas (10 m2/g), and ζ-potential values (-24 mV). The difference in the properties of TiO2 particles made it difficult to attribute the cytotoxicity solely to one variable.
ABSTRACT
Cancer is a major global public health problem and conventional chemotherapy has several adverse effects and deficiencies. As a valuable option for chemotherapy, nanomedicine requires novel agents to increase the effects of antineoplastic drugs in multiple cancer models. Since its discovery, carbon nanotubes (CNTs) are intensively investigated for their use as carriers in drug delivery applications. This study shows the development of a nanovector generated with commercial carbon nanotubes (cCNTs) that were oxidized (oxCNTs) and chemically functionalized with hyaluronic acid (HA) and loaded with carboplatin (CPT). The nanovector, oxCNTs-HA-CPT, was used as a treatment against HeLa and MDA-MB-231 human tumor cell lines. The potential antineoplastic impact of the fabricated nanovector was evaluated in human cervical adenocarcinoma (HeLa) and mammary adenocarcinoma (MDA-MB-231). The oxCNTs-HA-CPT nanovector demonstrate to have a specific antitumor effect in vitro. The functionalization with HA allows that nanovector bio-directed towards tumor cells, while the toxicity effect is attributed mainly to CPT in a dose-dependent manner.
