We had a problem with contamination of our plasmid. What kind of screening or removal do you recommend for endotoxin?

Answer

There are two basic options for low endotoxin plasmid preparations: perform your own preparations and endotoxin testing or contract the preparations to an outside company. The decision which option is best comes down to weighing resources versus efficiency and is highly dependent upon your available lab resources, timeline, scale and final application. For in-house preparation, utilize a commercially available plasmid prep kit that specifies low endotoxin or endotoxin-free plasmid preparation. Plasmid preparations can then be tested with a commercially available LAL (limulus amebocyte lysate) assay kit. Alternatively, send your plasmid(s) to a company with plasmid production services, such as Aldevron that offers plasmid manufacturing for both research grade, GMP-source and GMP plasmids.