title: High-throughput detection of ethanol-producing cyanobacteria in a microdroplet platform.
abstract: Ethanol production by microorganisms is an important renewable energy source. Most processes involve fermentation of sugars from plant feedstock, but there is increasing interest in direct ethanol production by photosynthetic organisms. To facilitate this, a high-throughput screening technique for the detection of ethanol is required. Here, a method for the quantitative detection of ethanol in a microdroplet-based platform is described that can be used for screening cyanobacterial strains to identify those with the highest ethanol productivity levels. The detection of ethanol by enzymatic assay was optimized both in bulk and in microdroplets. In parallel, the encapsulation of engineered ethanol-producing cyanobacteria in microdroplets and their growth dynamics in microdroplet reservoirs were demonstrated. The combination of modular microdroplet operations including droplet generation for cyanobacteria encapsulation, droplet re-injection and pico-injection, and laser-induced fluorescence, were used to create this new platform to screen genetically engineered strains of cyanobacteria with different levels of ethanol production.
authors: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
authors: Sara
authors: S
authors: Abalde-Cela
authors: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK Institute of Process Engineering, ETH Zurich, Sonneggstrasse 3, 8092 Zurich, Switzerland.
authors: Anna
authors: A
authors: Gould
authors: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK Sphere Fluidics, The Jonas Webb Building, Babraham Research Campus, Babraham, Cambridge CB22 3AT, UK.
authors: Xin
authors: X
authors: Liu
authors: Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.
authors: Elena
authors: E
authors: Kazamia
authors: Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK as25@cam.ac.uk.
authors: Alison G
authors: AG
authors: Smith
authors: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK ca56@cam.ac.uk.
authors: Chris
authors: C
authors: Abell
mesh_terms: D061249:Batch Cell Culture Techniques / Q000295:instrumentation; D002469:Cell Separation / Q000295:instrumentation*; D000458:Cyanobacteria / Q000145:classification / Q000302:isolation & purification* / Q000378:metabolism*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D000431:Ethanol / Q000032:analysis / Q000378:metabolism*; D005434:Flow Cytometry / Q000295:instrumentation; D057166:High-Throughput Screening Assays / Q000295:instrumentation*; D056656:Lab-On-A-Chip Devices
chemical_list: D000431:Ethanol
keywords: biofuels; cyanobacteria; fluorescence; microdroplets