The in vitro toxicity evaluation of halloysite nanotubes (HNTs) in human lung cells

Abstract

Halloysite nanotubes (HNTs) have been increasingly used in many industrial and biomedical fields. Therefore, the assessment of risk and consequences of exposure to HNTs is very important to better protect human safety. This study aims to investigate the short- (24 or 72 h) and long-term (7 days) cytotoxic effects of HNTs at doses 10–200 µg/mL on human alveolar carcinoma epithelial cells (A549) and human bronchial epithelial cells (BEAS-2B). The effect of HNTs on cell viability, apoptosis, cell proliferation, oxidative/antioxidative status and cell morphology was evaluated. Our results showed that cytotoxicity of HNTs is dependent on dose, cell model and time of exposure. During the time of exposition toxic effects were intensified. To the best of our knowledge, this is the first study to use holo-tomographic microscopy (HTM) to visualise changes in cell morphology due to exposure from HNTs. We observed cells contraction, changes in the size and shape, cell surface folding and cytoplasmic vacuolization, peripheral arrangement of cell nuclei and even increase number of nucleus, which undoubtedly confirmed cytotoxic effect of HNTs at low doses (5 µg/mL and 25 µg/mL). Our results demonstrated that HTM technique provides a new insight into the assessment of HNTs toxicity. Further studies with different cell models are recommended to assess the toxic effect of HNTs on whole human body.

Assessing cytotoxicity and endoplasmic reticulum stress in human blood–brain barrier cells due to silver and copper oxide nanoparticles

“…We previously reported that holotomographic microscopy could be used to observe morphological cell arrangements after low NP dose exposure exposure (Sawicka et al 2021;Zapor et al 2022). Herein, our results suggested that Ag-NP and CuO-NP doses below IC 50 values induced morphological changes and adverse events in cells.…”

Nanomaterials: A Review about Halloysite Nanotubes, Properties, and Application in the Biological Field

“…After 72 h of exposure, the IC 50 values decreased to 49 ± 3 μg/mL in A549 and 45.1 ± 8 μg/mL, in BEAS-2B cells. Thus, the results showed that cytotoxicity of HNTs depends on cell model, dose, and time of exposure [ 81 ]. Table 1 shows some of the toxicity threshold values reported for different concentrations of HNTs regarding cell types.…”

Water-dispersible X-ray scintillators enabling coating and blending with polymer materials for multiple applications

“…Other attractive properties of HNTs include their good biocompatibility 30 , 31 , low toxicity 32 , high stability 33 , hydrophilicity 34 , processability 35 , and low-cost 36 making HNTs promising candidates for the fabricating of composite materials. Though there is still some controversy on the potential toxicity upon some special items 37 , HNTs remain a popular topic in material science including biomedical uses with a growing trend of attention 38 . The existence of silanol groups on the surface allows straightforward surface functionalization 36 , 39 .…”