Skip to main content

Table 1 Intra- and inter-run variability of real-time PCR reactions. Intra- and inter-run variability was assayed for 5% RRS standard reference material, diluted to contain approximately 100, 20, 5, 1 and 0.5 ng of DNA. (Ct = Cycle threshold, SD = standard deviation of estimated copy number, CV = coefficient of variation of estimated copy number [%],* measurements outside the quantification range of the method)

From: Critical points of DNA quantification by real-time PCR – effects of DNA extraction method and sample matrix on quantification of genetically modified organisms

   intra-assay inter-assay CV attributed to final result
   Mean Ct Copy number estimate Mean Ct Copy number estimate  
  Amount of DNA   Mean SD CV   Mean SD CV  
lectin 100 ng (87000 copies) 22.12 76459 2652.86 3.47 22.21 76665 2136.80 2.79 7.3
  20 ng (17400 copies) 24.26 19179 514.26 2.68 24.26 19561 562.87 2.88 4.4
  5 ng (4350 copies) 26.38 4861 415.49 8.55 26.39 4705 145.13 3.08 12.5
  1 ng (870 copies) 28.98 895 32.08 3.58 28.89 884 38.35 4.34 10.4
  0.5 ng (435 copies) 30.25 392 20.92 5.33 30.06 403 13.71 3.40 10.9
RRS 100 ng (4350 copies) 27.99 4349 87.08 2.00 28.00 4017 273.05 6.80  
  20 ng (870 copies) 30.46 827 70.50 8.52 30.34 893 29.61 3.31  
  5 ng (218 copies) 32.39 224 23.36 10.41 32.51 223 27.00 12.10  
  1 ng (44 copies) 34.73 47 8.48 18.13 34.92 49 4.69 9.49  
  0.5 ng (22 copies) 35.90* 22 5.84 27.17 36.18* 22 2.30 10.34