Science in Short: Eli Lilly-Hard to Wet Surfaces

Highlighted is an example of a significant gel interface that formed between the tablet and the solution which was not observed to the same extent on Earth. Credits: Eli Lilly
Highlighted is an example of a significant gel interface that formed between the tablet and the solution which was not observed to the same extent on Earth. Credits: Eli Lilly

A few weeks ago I talked about an innovative applied research experiment being done aboard the International Space Station for Eli Lilly. They are interested in the process by which tablets dissolve, since this can be a problem for helping patients get the dose of medicine they need. Because microgravity allows study of diffusion without buoyancy or density-driven convection, these processes can be slower, allowing for better visualization and mathematical modeling.

The PIs of this experiment have allowed us to share the early visual results from their ISS experiment. In the image above, you can see an example of a significant gel interface that formed between the tablet and the solution which was not observed to the same extent on Earth. The ground controls are pending, but based on preliminary results, the rate of dissolution was significantly longer in the microgravity experiment, an unexpected and interesting result.

In chemistry, wetting refers to spreading of a liquid over a solid material’s surface, and is a key aspect of the material’s ability to dissolve. This investigation studies how certain materials used in the pharmaceutical industry dissolve in water while in microgravity. Results from this investigation could help improve the design of tablets that dissolve in the body to deliver drugs, thereby improving drug design for medicines used in space and on Earth.

NASA’s International Space Station Chief Scientist Julie Robinson, Ph.D. (NASA)
NASA’s International Space Station Chief Scientist Julie Robinson, Ph.D. (NASA)

Science in Short: ARTE

NASA astronaut Tim Kopra installed the Thermal Exchange hardware in the Microgravity Science Glovebox. Credits: NASA
NASA astronaut Tim Kopra installed the Thermal Exchange hardware in the Microgravity Science Glovebox. Credits: NASA

Our small devices have to dump a lot of heat from their electronics, if you have been sitting with your laptop on your lap wondering why it is getting so hot, you might also be interested in future improvements being sought through research on the International Space Station. Heat pipes are used to cool things like laptop computers and rely on an interface between liquid and gas phases in a liquid, plus capillary flow to return the cooled liquid back to the heated end. Previous research on the space station discovered inefficiencies in heat pipes and other research identified the new fundamental equations for capillary flow from research done on the orbiting laboratory. During the first week of April, and experiment called Advanced Research Thermal Passive Exchange (ARTE) , one of a number of new experiments testing this new knowledge to get practical applications, was completed on the space station. The Thermal Exchange hardware performed a series of powered test runs within the microgravity science glovebox to determine the impact of using various working fluids and different groove shapes on capillary action for heat pipes operating in a microgravity environment. The data collected will be used to further understand and validate numerical modelling of heat pipe behavior in microgravity, which can then be used to develop more passive and reliable thermal control systems for future exploration. This particular experiment was sponsored by the Italian Space Agency, and was led by scientists from DIMEAS – Dipartimento di Ingegneria Meccanica e Aerospaziale, I Facoltà di Ingegneria, Politecnico di Torino, Torino, Italy; related investigations testing various aspects of capillary flow and heat transfer are coming in the next few years, including some sponsored by CASIS as part of the ISS National Laboratory, and some sponsored by NASA.

NASA’s International Space Station Chief Scientist Julie Robinson, Ph.D. (NASA)
NASA’s International Space Station Chief Scientist Julie Robinson, Ph.D. (NASA)

Science in Short: BASS-M, Igniting Innovation on the Space Station

NASA astronaut Tim Kopra performs BASS-M operations in the Microgravity Sciences Glovebox in the Destiny Lab aboard the International Space Station.
NASA astronaut Tim Kopra performs BASS-M operations in the Microgravity Sciences Glovebox in the Destiny Lab aboard the International Space Station. Credits: NASA

Things have been heating up in the Microgravity Sciences Glovebox (MSG) in the Destiny Lab aboard the International Space Station as NASA astronaut, Tim Kopra performs operations for the BASS-M, a National Lab investigation which came about as a result of a partnership between CASIS and Milliken. Milliken is a commercial company who, among other things, produces custom engineering textiles, including flame-retardant ones used by a variety of industrial markets, such as the military and fire fighters.

Milliken is interested in seeing how the absence of gravity affects the burning of the textiles and materials. They are testing the hypothesis that materials in microgravity, with adequate ventilation, burn as well, if not better than, the same material being burned here on Earth under the same conditions.

NASA astronaut Tim Kopra tweeted this picture of a flame from the BASS-M operations.
NASA astronaut Tim Kopra tweeted this picture of a flame from the BASS-M operations. Credits: NASA

The investigation tests 10 different treated flame-retardant cotton fabrics at varying air flow rates, and studies their flammability and their ability to self-extinguish.

Ultimately, Milliken is using innovation in trying to design and engineer the right chemicals so that the textiles don’t burn. This applies specifically to the military and fire-fighters, for whom – if these textiles are designed correctly – could be protected from getting 2nd and 3rd degree burns.

Camille Alleyne, Ed.D., is an assistant program scientist for the International Space Station Program Science Office at NASA’s Johnson Space Center in Houston.
Camille Alleyne, Ed.D., is an assistant program scientist for the International Space Station Program Science Office at NASA’s Johnson Space Center in Houston.