High Throughput Fluorescent Screening of Membrane Potential and Intracellular Calcium Concentration Under Variable Gravity Conditions

In addition to the presence of specific gravity receptors in living organisms, biological membranes were found to directly respond to gravity changes. Among others, changes in membrane permeability and as a consequence in membrane potential and intracellular ion concentrations have been demonstrated mainly by using electrophysiological techniques. However, the acquired amount of data up to now is low due to technical limitations of electrophysiology in microgravity platforms. Optical techniques will be able to deliver much higher amounts of data here, especially in case high throughput techniques based on 96 well plate (or higher numbers of wells) readers can be used. In this manuscript we present a new set-up for parabolic flight campaigns based on a multi-purpose plate reader for photometric, luminescent and fluorometric measurements. In a first series of experiments during a parabolic flight campaign the system was verified for membrane potential and intracellular calcium concentration measurements of neuronal cells using fluorescent dyes.