Table 2.

Threshold Time Required for Turbidity of Solution to Exceed a Given Value with Various Templates

Sample preparation	Mean (SD) Tt value (min)
	HP-del	HP-5′
Detection limit of purified DNA
100 ng	24.9 (4.0)	23.7 (2.4)
10 ng	26.8 (4.2)	26.3 (2.8)
1 ng	30.9 (5.5)	30.0 (4.0)
0.1 ng	39.5 (5.3)	33.0 (5.4)
0.01 ng	—	32.7 (5.4)
0.001 ng	—	—
Serial dilution by NaOH
1:10	*	*
1:30	28.6 (1.5)	29.9 (2.4)
1:100	34.0 (3.7)	32.6 (3.9)
1:300	41.5 (10.1)	37.4 (2.5)
1:1000	45.8 (9.2)	37.9 (7.9)
1:3000	*	*
Water- or NaOH-diluted with/without heat
×2 with water and heat	31.8 (3.3)	33.3 (4.5)
×10 with water and heat	—	*
×100 with NaOH and heat	35.7 (4.0)	36.7 (5.4)
×100 with NaOH	31.4 (2.9)	32.2 (5.1)
Serial proportion of NaOH
1	33.5 (1.0)	35.4 (6.4)
2	35.4 (2.3)	36.0 (3.9)
4	42.4 (2.8)	42.8 (8.4)
8	—	—

Note: — represents the group in which turbidity was not observed, and asterisks represent the group in which turbidity was not consistently observed.

Tt, threshold time.