| AVS 66th International Symposium & Exhibition | |
| Chemical Analysis and Imaging Interfaces Focus Topic | Friday Sessions |
| Session CA+AS+NS+SE+SS-FrM |
| Session: | Novel Applications and Approaches in Interfacial Analysis |
| Presenter: | Jiyoung Son, Earth and Biological Sciences Directorate |
| Authors: | JY. Son, Earth and Biological Sciences Directorate J. Yao, Earth & Biological Sciences Directorate X.-Y. Yu, Pacific Northwest National Laboratory |
| Correspondent: | Click to Email |
Presentation Summary:
This presentation will showcase our latest results of the interaction between biofilms and synthetic bilgewater using a surface chemical imaging technique.
Abstract
Bilgewater, an oil-in-water (O/W) emulsion, is a persistent pollutant released to the ocean from the lowest part of ships. Microbes play an important role in the ocean. It is hypothesized that microbes release organics that can act as surfactants that affect bilgewater formation or weakening. We present the first systematic study of emulsions and biofilms and investigate the effects of biofilms on bilgewater emulsions. Three strains were selected Pseudomonas, Arthrobacter, and Cobetia marina. A Navy O/W emulsion consisting of three oils and a detergent mixture was used as the synthetic bilgewater model [1]. Biofilms were cultured in a microchannel to allow healthy culture [2]. Once a thick layer of biofilms was formed, the medium solution was changed to a mixture consisting of 50 % bilgewater emulsion. Dispersed biofilms were collected at 24 hrs. and 48 hrs. after emulsions were introduced into the channel. Bilgewater emulsions, biofilms, and mixtures of bilgewater emulsions and biofilms were analyzed using multiple in situ and ex situ techniques including time-of-flight secondary ion mass spectrometry (ToF-SIMS), scanning electron microscopy (SEM), and optical microscopy. Our findings indicate that biofilms change the chemical makeup of the emulsion surface compositions and emulsion droplet size distribution, confirming the hypothesis that extracellular polymeric substance (EPS) related components released from biofilms can function as surfactants and change the oil-in-water interfaces.
Key words: bilgewater emulsion, oil-in-water, microfluidics, biofilm, EPS, surfactant
Reference
1. Church, J., D.M. Paynter, and W.H. Lee, In Situ Characterization of Oil-in-Water Emulsions Stabilized by Surfactant and Salt Using Microsensors. Langmuir, 2017. 33(38): p. 9731-9739.
2. Yao, J., et al., In Situ Characterization of Boehmite Particles in Water Using Liquid SEM. J Vis Exp, 2017(127).