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We also evaluated our device for the detection of pathogen agents from the air sample using the installed rapid on-chip PCR device. BS spores were used as a simulant. The performance of our rapid on-chip PCR technology was previously reported23 [/articles/micronano201783#ref23]. A small volume of PCR solution was injected in the microchannel and formed the segment-flow through the perfused air and vapor pressures. When 2.5106 cfu of the BS spore simulant solution was collected by the generated mist and became concentrated in the reservoir, the estimated amount of the collected BS spores was 1.6105 cfu. The calculated concentration was approximately equivalent to 800cfuL1. Figure 5 shows the results of the amplified fluorescence intensity after the segment-flow PCRs with the various concentrations of BS spores. The flow rate of the PCR solution was adjusted to detect low concentrations of positive control. The flow rate was fixed at 24Lmin1, and the total reaction time was 12.5min for 40 cycles of the segment-flow PCR. Orange-colored bars indicate the fluorescence intensities after the segment-flow PCRs in cases of direct injection of 1000cfuL1 of BS spore solution and no template control (NTC) solution without the aerosol sampler: positive and negative controls, respectively. Blue bars indicate the results of the segment-flow PCRs using the aerosol sampler. These fluorescence intensities after the segment-flow PCRs do not only relate to the amount of the sprayed BS spores; these were also reasonable values between the results of both controls. While the BS spore solution was diluted 100 times (equal to 8cfuL1), the fluorescence was successfully increased compared with the NTC. Here, chemical agents should be used with the assumption that the lethal dose in air is for 1min of inhalation since the toxicity effect will appear immediately. Alternately, a pathogen agent should have the assumption that the lethal dose in air for 1h of inhalation, because the infection of a bacterium pathogen or virus takes propagation time and has the greater possibility of treatment. The infection dose of anthrax spores is 800050000 spores34 [/articles/micronano201783#ref34],35 [/articles/micronano201783#ref35]. If a human inhales approximately 8lmin1, the lethal dose of anthrax is calculated to be 16000 sporem3. If it is assumed that the infection can be medically treated with the administration of antibiotics after early discovery of the agent exposure, the safety margin of the lethal dose is increased by 10 times35 [/articles/micronano201783#ref35]. Thus, 54000 spores should be collected and detected, as required for anthrax sensitivity, when air is collected for 338lmin1 by our sampling device. A concentration of 8cfuL1, which was successfully detected by our device, has 25000 spores and covered the required sensitivity for anthrax detection. Therefore, it is expected that the sensitivity of the developed system would be enough for detecting biological warfare similar to anthrax spores. In addition, for 800cfumL1, the observed fluorescence intensity was 8.381.05 with a C.V. value of 12.5% (_n_=3) that demonstrate the reliability of the measurement.