Improving Quality in Nanoparticle-Induced Cytotoxicity Testing by a Tiered Inter-Laboratory Comparison Study

Area of Science:

• Nanotechnology
• Toxicology
• Materials Science

Background:

• Nanosafety studies face challenges in quality and relevance, hindering sustainable innovation.
• Increasingly contradictory research results necessitate harmonized protocols in nanosafety.
• Standardized testing is crucial for reliable nanomaterial risk assessment.

Purpose of the Study:

• To evaluate if best-practice training and inter-laboratory comparison (ILC) improve nanosafety testing quality.
• To assess the performance of the MTS assay for nanomaterial cytotoxicity assessment across multiple labs.
• To enhance the reproducibility of nanotoxicological data.

Main Methods:

• A tiered approach involving 15 European laboratories was employed.
• Standard Operating Procedures (SOPs) and shared materials (cells, serum, nanoparticles) were used.
• Inter-laboratory comparisons (ILCs) of the MTS assay were conducted before and after training.

Main Results:

• A tiered process with SOPs and control nanomaterials improved intra- and inter-laboratory reproducibility.
• Carboxylated polystyrene (PS-COOH) and amino-modified polystyrene (PS-NH2) were validated as control nanoparticles.
• The training and refined MTS assay SOP led to significantly better results in tier 3.

Conclusions:

• A tiered approach with SOPs and control nanomaterials is essential for high-quality nanotoxicological data.
• Best-practice training and ILC enhance inter-laboratory reproducibility in nanosafety testing.
• Standardized methods ensure the reliability of nanosafety data for sustainable innovation.