| AVS 65th International Symposium & Exhibition | |
| Biomaterial Interfaces Division | Wednesday Sessions |
| Session BI-WeA |
| Session: | Microbes and Fouling at Surfaces |
| Presenter: | Wenchao Wei, Pacific Northwest National Laboratory |
| Authors: | W. Wei, Pacific Northwest National Laboratory R. Komorek, Pacific Northwest National Laboratory C. Yang, Yantai Institute of Coastal Zone Research F. Liu, Yantai Institute of Coastal Zone Research Z.H. Zhu, Pacific Northwest National Laboratory X-Y. Yu, Pacific Northwest National Laboratory |
| Correspondent: | Click to Email |
We developed a vacuum compatible microfluidic interface, System for Analysis at the Liquid Vacuum Interface (SALVI), to enable direct observations of liquid surfaces and liquid-solid interactions using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and a variety of spectroscopy and microscopy characterization techniques. SALVI was recently applied to investigate biological interfaces in living biofilms and co-cultured microbial communities [1, 2]. In this talk, a more complex microbial communities consisting of syntrophic Geobacter metallireducens and Geobacter sulfurreducens was investigated using ToF-SIMS [3]. As a surface technique, in situ liquid SIMS provides direct measurement of initial attachment of the co-cultured aggregates. Our 3D imaging results give spatial distribution of amino acid fragments and lipids, indicative of the role of proteins and lipids played in the co-cultured aggregate formation. The planktonic cells seem to show strong evidence of hydrogen transfer in liquid by the direct observations of lipid fragments with the addition of water and hydrogen. This pheromone indicates that higher direct electron interspecies transfer may exist in co-culture aggregates whereas hydrogen transfer is dominant in planktonic cells. More interestingly, distinct water distribution is observed between co-cultured aggregates and planktonic cells, indicating the change of hydrogen bonding as a result of the complex microbial syntrophic community communication. Our results demonstrate that interfacial chemistry involving living microbial systems can be studied from the bottom up based on microfluidics, potentially providing more important understanding in system biology.
Key words: microfluidics, biofilm, co-cultured aggregate, electron transfer, EPS, ToF-SIMS
References:
1. X. Hua et al., In situ molecular imaging of hydrated biofilm in a microfluidic reactor by ToF-SIMS, Analyst, 139 (7), 1609-1613, 2014.
2. W. Wei et al., Characterization of syntrophic Geobacter communities using ToF-SIMS, Biointerfaces, 12 (5), 05G601, 2017.
3. Y. Ding et al.,In situmolecular imaging of the biofilm and its matrix, Analytical Chemistry, 88 (22), 11244-11252, 2016