Toxicity evaluation of biodegradable chitosan nanoparticles using a zebrafish embryo model

Area of Science:

• Nanotechnology
• Biomaterials Science
• Toxicology

Background:

• Limited safety data exists for biodegradable nanomaterials, despite their common use.
• Chitosan nanoparticles, frequently used in drug/gene delivery, have largely uncharacterized toxicity.
• The zebrafish model is employed for evaluating the safety of nanocarriers.

Purpose of the Study:

• To assess the potential toxicity of chitosan nanoparticles using a zebrafish model.
• To investigate the concentration-dependent effects of chitosan nanoparticles on zebrafish embryos.
• To compare the toxicity of chitosan nanoparticles with a known toxicant, zinc oxide nanoparticles.

Main Methods:

• Chitosan nanoparticles of two sizes were synthesized via ionic cross-linking with sodium tripolyphosphate.
• Zebrafish embryos were exposed to varying concentrations of chitosan nanoparticles and zinc oxide nanoparticles.
• Standard toxicological endpoints including hatching rate, mortality, and malformations were assessed.

Main Results:

• Both chitosan and zinc oxide nanoparticles exhibited concentration-dependent decreases in hatching rates and increased mortality.
• Exposure to 200 nm chitosan nanoparticles induced significant malformations in zebrafish embryos, such as bent spines and pericardial edema.
• Chitosan nanoparticle exposure led to increased cell death, elevated reactive oxygen species, and heat shock protein 70 overexpression, indicating physiological stress.

Conclusions:

• Biodegradable nanocarriers like chitosan nanoparticles possess inherent toxicity that requires careful consideration.
• These findings contribute to understanding the nanotoxicity of drug delivery systems.
• Further research is needed to address the in vivo safety of biodegradable nanomaterials.