Optimized chemiluminescent detection of DNA amplified in the exponential phase of PCR.

We describe a procedure for quantitative detection of nucleic acids by coupling PCR with improved chemiluminescent detection techniques. After performing PCR in the exponential phase in the presence of a trace amount of digoxigenin-11-dUTP, the amplified products are transferred to a positively charged nylon membrane. The membrane is cleaned with a modified method involving sodium dodecyl sulfate and ethanol washing steps to ensure low backgrounds in chemiluminescent detection. The membrane is exposed to two stacked x-ray films to increase the dynamic response in a film exposure. This sensitive and quantitative procedure is useful for molecular biology studies.