खुली मीडिया में माइक्रोबियल परिवहन अध्ययन करने के लिए सरल Microfluidic सिस्टम: MicroWorld पर खिड़की
1Vanderbilt Institute for Integrative Biosystems Research and Education,Vanderbilt University, 2Department of Biomedical Engineering,Vanderbilt University, 3Department of Molecular Physiology and Biophysics,Vanderbilt University, 4Department of Physics and Astronomy,Vanderbilt University, 5Department of Chemical, Materials and Biomolecular Engineering,University of Connecticut, 6Center for Environmental Sciences and Engineering,University of Connecticut
Summary
Microfluidic उपकरणों के लिए वास्तविक समय में और उपयुक्त शारीरिक पैमाने पर जटिल प्राकृतिक प्रक्रियाओं कल्पना करने के लिए इस्तेमाल किया जा सकता है. हम एक सरल microfluidic युक्ति है कि उपसतह में जीवाणुओं के विकास को परिवहन के अध्ययन के लिए प्राकृतिक झरझरा मीडिया की प्रमुख विशेषताओं mimics विकसित किया है.
Abstract
Microbial growth and transport in porous media have important implications for the quality of groundwater and surface water, the recycling of nutrients in the environment, as well as directly for the transmission of pathogens to drinking water supplies. Natural porous media is composed of an intricate physical topology, varied surface chemistries, dynamic gradients of nutrients and electron acceptors, and a patchy distribution of microbes. These features vary substantially over a length scale of microns, making the results of macro-scale investigations of microbial transport difficult to interpret, and the validation of mechanistic models challenging. Here we demonstrate how simple microfluidic devices can be used to visualize microbial interactions with micro-structured habitats, to identify key processes influencing the observed phenomena, and to systematically validate predictive models. Simple, easy-to-use flow cells were constructed out of the transparent, biocompatible and oxygen-permeable material poly(dimethyl siloxane). Standard methods of photolithography were used to make micro-structured masters, and replica molding was used to cast micro-structured flow cells from the masters. The physical design of the flow cell chamber is adaptable to the experimental requirements: microchannels can vary from simple linear connections to complex topologies with feature sizes as small as 2 μm. Our modular EcoChip flow cell array features dozens of identical chambers and flow control by a gravity-driven flow module. We demonstrate that through use of EcoChip devices, physical structures and pressure heads can be held constant or varied systematically while the influence of surface chemistry, fluid properties, or the characteristics of the microbial population is investigated. Through transport experiments using a non-pathogenic, green fluorescent protein-expressing Vibrio bacterial strain, we illustrate the importance of habitat structure, flow conditions, and inoculums size on fundamental transport phenomena, and with real-time particle-scale observations, demonstrate that microfluidics offer a compelling view of a hidden world.
Protocol
मैं Microfluidic डिवाइस निर्माण एक microfluidic युक्ति बनाने में पहला कदम एक कंप्यूटर सहायता ड्राइंग प्रोग्राम (सीएडी) में डिवाइस के एक दो आयामी लेआउट आकर्षित है. हम AutoCAD का इस्तेमाल किया है, लेकिन अन्य आरेखण प्रोग्…
Discussion
EcoChip प्रणाली एक व्यक्ति के प्रयोग की जरूरतों के लिए अनुकूलनीय है. नए स्वामी अपेक्षाकृत आसानी से बनाया जा सकता है, और एक बार एक मास्टर गढ़े है, बिल्कुल दोहराया अतिरिक्त उपकरणों जरूरत के रूप में डाली जा सकत…
Acknowledgements
इस अध्ययन के अनुदान # 0649883 द्वारा एकीकृत Biosystems अनुसंधान और शिक्षा (VIIBRE) के लिए Vanderbilt संस्थान द्वारा राष्ट्रीय विज्ञान फाउंडेशन, और Searle सिस्टम्स बायोलॉजी और बायोइन्जिनियरिंग अंडर ग्रेजुएट रिसर्च अनुभव (Searle SyBBURE) द्वारा समर्थित किया गया.
Materials
| Material Name | Type | Company | Catalogue Number | Comment |
|---|---|---|---|---|
| PDMS | Dow Corning | |||
| SU8-2025 | MicroChem Corp. | |||
| Fluorescent Beads | Polysciences, Inc. |
References
- Whitesides, G., Ostuni, E., Takayama, S., Jiang, X., Ingber, D. Soft lithography in biology and biochemistry. Annual Review of Biomedical Engineering. 3, 335-373 (2001).
- Wang, W., Shor, L. M., LeBoeuf, E. J., Wikswo, J. P., Kosson, D. S. Mobility of protozoa through narrow channels. Applied and Environmental Microbiology. 71, 4628-4637 (2005).
Cite This Article
Markov, D. A., Samson, P. C., Schaffer, D. K., Dhummakupt, A., Wikswo, J. P., Shor, L. M. Window on a Microworld: Simple Microfluidic Systems for Studying Microbial Transport in Porous Media. J. Vis. Exp. (39), e1741, doi:10.3791/1741 (2010).