Fig. 2

The quantification of (pro)-inflammatory cytokine IL-6 (a) and chemokine IL-8 (b) was performed following a 24-h exposure to test ENMs, LPS (100 ng/ml) served as the positive control. Cellular supernatant was harvested and stored appropriately until required. IL-6 showed low levels of activation at concentrations 2-8 µg/ml before a dose-dependent response was initiated with amine-FLG and carboxyl-FLG exceeding the levels reached by TT1 exposures to LPS. IL-8 levels were initially activated at 2-8 µg/ml before a dose dependent rise was observed becoming significant at 20 µg/ml whilst not exceeding LPS levels of activation. Results were considered significant (*) when p < 0.05. Data is presented as the average value ± the standard deviation (SD), (N = 3)