The horizontal axis indicates the event number of six DNA targets and the vertical axis indicates sample amplitude. The positive and negative droplets as classified by Thresholds (pink lines) of individual wells are shown in blue and grey, respectively. Thresholds of RLEP (A), esxA (C), pra (D), HSP18 (E) and Ag85 (F) for positive detection are set to 5,000, and Threshold of groEL (B) is set to 2,500. The different amplitudes of positive droplets were observed when different DNA targets were applied (RLEP, Pos: 782, Neg: 14,436; groEL, Pos: 769, Neg: 13,536; esxA, Pos: 22, Neg: 16,386; pra, Pos: 12, Neg: 15,029; HSP18, Pos: 21, Neg: 16,494; Ag85B, Pos: 26, Neg: 15,283). The total positive and negative droplets of six DNA targets are 1,632 and 91,164, respectively.