Figure 2.
Determination of endotoxin concentration in PLA disks. Endotoxin concentration was determined in supernatants of PLA strings before printing directly after unpacking (red circle 5) and after a few days at the air (red circle 6) and in PLA disks after printing incubated for 24 h (1 + 2) or 48 h (3 + 4): green circles. The trendline corresponds to standards with 0.1, 0.25, 0.5 and 1.0 EU/mL (black quarders). The diagram shows that endotoxin concentrations are well below the FDA limit of 0.5 EU/mL.