Fig. 3
Metabolic disturbances in MNPs@SiO2(RITC)-treated BV2 cells. a Star patterns for 13 fatty acids (FAs; left), 20 amino acids (AAs; middle), and 11 organic acids (OAs; right) in BV2 cells treated with 0.01 or 0.1 µg/µl MNPs@SiO2(RITC) and no-treatment control cells. *p < 0.05 for no-treatment control versus 0.01 µg/µl MNPs@SiO2(RITC), §p < 0.05 for no-treatment control versus 0.1 µg/µl MNPs@SiO2(RITC), and #p < 0.05 for 0.01 µg/µl versus 0.1 µg/µl MNPs@SiO2(RITC). b The metabolomic network of 0.1 µg/µl MNPs@SiO2(RITC)–treated BV2 cells using IPA. This analysis employed a fold-change cut-off value ≥  ± 1.2. Details for shape and color are provided in Figs. S9 and S11. c The trimmed metabolomic network with prediction for four categories of biological functions. Orange and blue arrows indicate prediction of activation and inhibition, respectively. d Representative selected-ion monitoring chromatograms of stearic acid, glycine, methionine, and lactic acid for (i) control, (ii) 0.01, and (iii) 0.01 µg/µl MNPs@SiO2(RITC)–treated BV2 cells