High temporal resolution detection and analysis of metabolites released during bacterial proliferation using PTR-MS

Volatile organic compounds (VOCs) released by bacteria during proliferation have the potential to be used for rapid bacterial identification. VOCs change rapidy during the proliferation. However, the current studies are mostly based on single-point or long-time-interval sampling, which may lead to the omission of metabolic information. In this study, we developed an integrated device for bacterial culture-headspace injection-mass spectrometry detection. Using this device, we conducted high temporal resolution detection and analysis of headspace VOCs from E. coli, P. aeruginosa, and S. aureus. The detection interval was 10 min. The results showed that the VOCs released by the three bacteria caused the elevation of 30 ions in the mass spectrum. These ions exhibited complex regular changes in each bacterium. While the changing trends of some ions are significantly different among the three bacteria. For VOCs that exhibited a pattern of initially increasing and then decreasing, widening the sampling interval can lead to crucial information being missed. This may be an important factor contributing to differences in the detection of VOCs released by bacteria in previous studies. Therefore, the high temporal resolution detection method developed in this study can more accurately trace the changing trend of bacterial VOCs and provide technical support for bacterial identification methods based on VOC detection.