DETECTION OF GENETICALLY MODIFIED MAIZE BY PCR AND CAPILLARY GEL ELECTROPHORESIS (CGE) USING UNCOATED COLUMNS.

In this work, analysis of genetically modified insect-resistant Bt maize is demostrated by combining amplification of a DNA fragment by PCR and subsequent detection by Capillary Gel Electrophoresis (CGE). A new CGE method is developed that allows obtaining reproducible separations of DNA fragments using bare fused silica capillaries. The method combines a washing routine of the column with 0.1 M hydrochloride acid followed by a rinsing step with a dissolution containing 1 % polyvinyl alcohol. The use of this procedure together with a running buffer containing 2-hydroxyethyl cellulose (HEC) at pH 7.3 gives highly resolved and fast separations of DNA fragments ranging from 80 to 500 bp and great reproducibility. This procedure would allow the simultaneous quantitation of several GMOs in foods in a single run. To our knowledge, this is the first report on the use of PCR combined with CGE to detect transgenic foods. 1