Discriminant analysis of pathogen specific VOCs from lung tissue model. A. GC-MS analysis of VOCs from different pathogens incubated lung tissue model, blanked with sterile saline; B. Multivariate Discriminant Logistic Analysis of VOCs from different pathogen groups (1. S.aureus, 2. E.coli, 3. Pseudomonas, 4. Sterile saline); C. Discriminating VOC pattern in animal model; D. Multivariate Discriminant Analysis of VOCs from different pathogen groups (1. S.aureus, 2. E.coli, 3. Pseudomonas, 4. Sterile saline).