the present invention provides a sensitive and robust analytical approach to identifying and quantifying multiple pathogens within a single complex environmental sample . numerous nucleic acid signatures may be screened and quantified within a single reaction tube using polymerase chain reaction and chromatographically analyzing the amplification products with microchannel fluidic or reverse - phase ion - pairing high - performance liquid chromatography rp ip hplc instruments . the method may be employed in a multiplex fashion to allow identification and quantification of multiple combinations of up to five different nucleic acid signatures simultaneously within a single multiplex pcr reaction tube . this approach is quantitative across a dynamic range of up to five orders of magnitude . this method is suitable for target nucleic acid analysis in medium or high - throughput contexts such as routine clinical diagnotics or environmental monitoring . the method is also suitable for pathogen monitoring or surveillance in a biodefense context .