Single drop cytometry onboard the International Space Station

Area of Science:

• Space biology
• Biomedical engineering
• Analytical chemistry

Background:

• Clinical decision-making and research for space missions require real-time laboratory analysis.
• Conventional powerful lab instruments like flow cytometers are too large and complex for spaceflight.
• Astronaut health monitoring necessitates in-situ diagnostic capabilities, reducing reliance on Earth-based labs.

Purpose of the Study:

• To adapt and validate a miniature flow cytometer (rHEALTH ONE) for microgravity laboratory analysis.
• To demonstrate the feasibility of performing microvolume flow cytometry in space for astronaut health management.
• To enable real-time biological research and diagnostics during human space exploration.

Main Methods:

• Modified the rHEALTH ONE analyzer with bubble-free fluidics, electromagnetic shielding, and gravity-independent sample introduction for spaceflight.
• Utilized microvolume samples (10 μL) for flow cytometry in microgravity.
• Collected multi-channel data with high temporal resolution (10 μs bin intervals).

Main Results:

• Achieved microgravity flow cytometry with minimal resource utilization and alignment-free optics.
• Generated an average of 72 million raw data points per sample in approximately 2 minutes.
• Demonstrated repeatable measurements and accurate identification of sample degradation during transit to the International Space Station.

Conclusions:

• The modified rHEALTH ONE analyzer is suitable for spaceflight, enabling microgravity flow cytometry.
• This technology provides immediate, actionable diagnostic information for astronaut health management.
• Facilitates advancements in understanding spaceflight biology and supports long-duration human missions.