Cellular uptake of 30 nm and 400 nm SiO
NP. THP-1 (A, B) and A549 (C, D) cells growing on 96-well plates were exposed to various concentrations (0.01, 0.1, or 0.5 mg/ml) of 30 nm (A, C) or 400 nm (B, D) SiO2NP for multiple time points ranging from 15 min to 24 h. High content screenings analysis for the cytosolic accumulation of these particles was performed using an automated IN Cell Analyzer 1000 microscope and IN Cell Investigator image analysis software. Relative fluorescence intensity (RFU) represents the average intensity value of cytosolic accumulation of these labelled nanoparticles when measured in PBS at pH 7.4. Data shown is normalised to untreated control and presented as mean values of three independent experiments performed in triplicate samples. 2-way ANOVA with Bonferroni post-test analysis was carried out on the experimental data, normalised to controls, and statistically significant data is reported by "*" symbol, for p < 0.05; "**" p < 0.01; "***" for p < 0.001.