Table 1.

Efficiencies of DNA extraction of different amounts of cells of E. coli ATCC 11775^T and S. aureus subsp. aureus ATCC 25923 by three different methods: FTA® Elute, the Reischl et al. method and QIAamp® DNA Mini Kit

Number of cells		5.3 × 105	5.3 × 104	5.3 × 103	5.3 × 102	5.3 × 101
		Median % (n = 4)
E. coli ATCC 11775T	FTA® Elute	40.5	84.8	96.3	BCd	BCd
	Reischl et al.	48.9	59.6	24.5	BCb	ND
	QIAamp® DNA Mini Kit	4.6	32.3	13.5	BCb	BCc
S. aureus subsp. aureus ATCC 25923	FTA® Elute	112.6	94.9	119.4	BCb	BCc
	Reischl et al.	10.2	8.8	8.5	BCb	BCa
	QIAamp® DNA Mini Kit	69.4	117.0	97.7	149.9	BCa

ND, not detected; BC, below cut-off level, i.e. not all of the reactions were positive and quantifiable

^aFour, ^bthree, ^ctwo and ^done of four reactions produced a positive result