BANGALORE: The device developed by the team uses an LED and photodiode sensor combination to track bacterial growth
What happens to microbes in outer space? Will their behaviour patterns in such an extreme environment give us insight to help future space missions? With these questions in mind, a team of researchers at the Indian Institute of Science (IISc.) and Indian Space Research Organisation (ISRO) have developed a modular, self-contained device to cultivate microorganisms. This could enable scientists to carry out biological experiments in outer space, said IISc. via a press release.
In a paper published in the peer reviewed journal Acta Astronautica, the team showed how the device can be used to activate and track the growth of bacterium ‘Sporosarcina pasteurii’ over several days, with minimal human involvement. “Understanding how such microbes behave in extreme environments could provide valuable insight for human space missions such as ‘Gaganyaan’, India’s first crewed spacecraft set to be launched in 2022,” stated the release.
The study of microbes in extreme conditions is a growing field. “In recent years, scientists have been increasingly exploring the use of lab-on-chip platforms ‒ which combine many analyses into a single integrated chip ‒ for such experiments,” they said in the release. However, designing such platforms to function effectively in outer space poses additional challenges as conditions are vastly different from lab settings.
“It has to be completely self-contained,” said Koushik Viswanathan, assistant professor in the Department of Mechanical Engineering and a senior author of the study. “You can’t simply expect the same operating conditions as you would in a normal laboratory setting … and you can’t have something that guzzles 500W, for example.”
The device developed by the team uses an LED and photodiode sensor combination to track bacterial growth. The device has separate compartments for different experiments. Each compartment or ‘cassette’ consists of a chamber where bacteria ‒ suspended as spores in a sucrose solution ‒ and a nutrient medium can be mixed to kickstart growth, by flicking on a switch remotely.
“Data from each cassette is collected and stored independently. Three cassettes are clubbed into a single cartridge, which consumes just under 1W of power. The researchers envision that a full payload that could go in a spacecraft will contain four such cartridges capable of carrying out 12 independent experiments,” stated the release.
Another challenge was to build a device that is leak-proof and unaffected by any change in orientation. “This is a non-traditional environment for the bacteria to grow. It is totally sealed and has a very small volume. We had to see whether we would get consistent [growth] results in this smaller volume,” says Aloke Kumar, associate professor in the Department of Mechanical Engineering, and another senior author. “We also had to make sure that the LED going on and off doesn’t generate much heat, which can change the bacterial growth characteristics.”