Measuring Supercoiling

Quality is a major issue in plasmid DNA manufacturing process in order to keep with the strict FDA and EMA guidelines for therapeutic use in humans. Therefore, it is necessary for industries to determine the superhelical density of the final product of supercoiled plasmid DNA. The current supercoiling assay involves usage of gel electrophoresis with chloroquine and ethidium bromide as the key materials for the separation and visualisation of the plasmid DNA of various superhelical density. Such assays are quite lengthy and involves handling of carcinogenic chemicals like ethidium bromide. The idea of the ‘supercoilometer’ is to provide an useful accessory tool for plasmid DNA manufacturing industries to monitor and measure the superhelical density of their target plasmid in vivo and in live time.