Comparison of quantitative HDA and PCR methods from μSPE channel extracted DNA. E. coli DNA from 105 to 101CFU total was extracted by μSPE channels in triplicate. (a) Real time quantitative HDA and PCR results are shown for amplification of the dxs gene. Reactions were performed in an Applied Biosystems 7300 PCR thermocycler. PCR cycling conditions: 50°C, 2 min; 95°C, 10 min; 40 cycles of 95°C, 15 s; 55°C, 1 min. HDA cycling conditions: 40 cycles of 66°C, 5 s; 65°C 1 min 55 s. (b) The average Ct and time to detection of the HDA versus PCR products was determined