By Nanotechnology Characterization Laboratory (NCL)
Microbial and endotoxin contamination can be common in a laboratory setting, and in many cases, contamination won't significantly affect results of early development studies. However, many of the assays conducted at the NCL, especially immunological assays, can be susceptible to microbial and endotoxin contamination, leading to misinterpretation of the data. Therefore, all materials submitted to the NCL undergo screening for these contaminants prior to any subsequent studies. To aid developers struggling with these contaminants, the NCL has prepared a guide with tips on how to test for sterility and endotoxin levels, minimize contamination during preparation, and remove or reduce endotoxin levels in samples. In addition, the NCL has published a video in the Journal of Visualized Experiments with recommendations on performing the various limulus amoebocyte lysate (LAL) assays for detection of endotoxin. Detection of Endotoxin Contamination: STE-1.1 End point chromogenic LAL assay; STE-1.2 Kinetic turbidity LAL assay; STE-1.3 Gel-clot LAL assay; STE-1.4 Kinetic chromogenic LAL assay; Endotoxin and Depyrogenation Tips; Detection of endotoxin in nano-formulations using limulus amoebocyte lysate (LAL) assays - JoVE video protocol. Detection of Microbial Contamination: STE-2.1 Detection of microbial contamination using Millipore Sampler devices; STE-2.2 Detection of bacterial contamination using Luria broth agar plates; STE-2.3 Detection of bacterial contamination using tryptic soy agar plates; STE-2.4 Detection of bacterial contamination using tryptic soy agar plates and RPMI suspension for determination of bacterial identification; STE-3 Detection of mycoplasma contamination. Detection of β-Glucan Contamination: STE-4 Detection of β-glucan contamination.
