Fluidics Subsystem for GeneSat Experimental Payload
NASA Ames Research Center, Moffett Field, CA 94035
Introduction
The GeneSat experimental payload was designed to perform both fluorescence and optical density assays of biological specimens in an automated fashion. Below is a brief look at the functionality and components which comprise the fluidic card subsystem.
Functionality
Samples of E. coli are dispensed into an assay well with a 6.5 mm diameter and 3.0 mm depth. The assay wells are spaced on an 18 mm grid to facilitate ground-based studies using laboratory equipment that can read SBS standard
microtiter plates. After E. coli introduction, the assay well is sealed with a membrane using a pressure-sensitive adhesive, and the assay wells are filled with stasis media via the fluidic channels.
The fluidic card features one inlet fluidic channel and one outlet fluidic channel per assay well. Membranes across the fluidic channels on either side of the assay well allow fluid flow but restrict E. coli from escaping through the fluidic channels.
During the initiation of the experiment, the fluidic system delivers experimental media required for E. coli growth to each well through the fluidic channels using a pump and valve system. The stasis media is displaced by the experimental media, and exits the assay well.
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Figure 1. 12 well prototype fluidic card.
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Figure 2. Fluidic connector.
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