Metabolically active cells emit volatile organic compounds (VOCs) that can be used in real time to non-invasively monitor the health of cell cultures. We utilized these naturally occurring VOCs in an adapted culture method to detect differences in culturing Chinese hamster ovary (CHO) cells with and without Staphylococcus epidermidis and Aspergillus fumigatus contaminations. The VOC emissions from the cell cultures were extracted and measured from the culture flask headspace using polydimethylsiloxane (PDMS)-coated Twisters, which were subjected to thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) analysis. In our initial time points of 1 and 2 h, we detected VOC signatures that differentiated the cultures earlier than traditional plating techniques or visualization methods. Partial least squares-discriminant analysis (PLS-DA) models were built to differentiate the analytes from the CHO cells and S. epidermidis- and A. fumigatus-inoculated CHO cultures. A total of 41 compounds with a variable importance in projection (VIP) score greater than 1 was obtained across the models. Similarly, based on the PLS regression analyses to predict the cell concentration of S. epidermidis (R2 = 0.891) and A. fumigatus (R2 = 0.375), 15 and 20 relevant compounds were putatively identified, respectively; two known compounds overlapped between the two microbes. Some of the compounds were unidentified and future studies will deter- mine the relationship between the VOCs and the metabolic changes in contaminated cultures.
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Identifying Alkali-Silica Reaction in Cementitious Materials Using Volatilomics
For millennia, the medical field has utilized the sense of smell for qualitative assessment of health, but recent research shows we can tap into volatile organic compounds (VOCs), which create the odors that we perceive, for quantitative detection and analysis. In this paper, volatile organic compounds produced by the microbes in aged concrete, actively undergoing deterioration due to alkali-silica reaction were analyzed. Volatile organic compounds metabolites, an oft unused resource of chemical information that are produced by concrete-associated microbial communities, were used to detect, and characterize concrete deterioration. In this talk, preliminary results of volatile detection on long-term samples (e.g., ~ 7 years) will be provided. Scanning electron microscopy with energy disperse x-ray analysis was used to confirm deterioration mechanisms identified using volatilomics. Volatiles were analyzed using direct thermal extraction (DTE) and comprehensive two-dimensional gas chromatography - time-of-flight mass spectrometry (GC × GC–TOFMS). Identifying VOC biomarkers of concrete health will lay the groundwork for the development of sensors that can provide early deterioration warning, enabling more effective remediation/repair strategies. Microbes may also be sensitive to environmental stress (e.g., climate change), and a sensor based on microbial volatile organic compounds could be used to monitor infrastructure health and provide data to detect environmental stressors relevant to other fields.
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- Award ID(s):
- 2227497
- PAR ID:
- 10584095
- Editor(s):
- Sanchez, Leandro F; Trottier, Cassandra
- Publisher / Repository:
- Springer Nature Switzerland
- Date Published:
- ISSN:
- 978-3-031-59418-2
- ISBN:
- 978-3-031-59419-9
- Page Range / eLocation ID:
- 615 to 623
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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