Figure 6From: Contamination of nanoparticles by endotoxin: evaluation of different test methods TLR4 reporter cells when performed in the presence of particles (12.5, 50 and 200 μg/ml) after spiking. Samples spiked with endotoxin concentrations half of assay sensitivity (½λmax: 0.3 EU/ml). Results are shown in a heat plot: Red: no spike recovery; Green: complete spike recovery (between 50 and 200%). Percentages indicate percentage spike recovery.Back to article page