Parameters of sigmoidal amplification curves at different DNA concentrations.

DNA concentration (pg μl−1)	A	B	t 0.5	k	R 2
6175	0.708	0.282	19.55	−4.195	0.995
617.5	0.691	0.311	20.97	−4.130	0.994
61.75	0.696	0.317	21.78	−4.441	0.996
6.175	0.716	0.298	23.11	−4.231	0.994
0.06175	0.709	0.304	32.75	−5.445	0.997
0.006175	0.656	0.356	48.08	−10.85	0.988