Down to Earth: BioLab

Stuart Higgins is on the case in this week's Down to Earth...

‘Biolab’ is a semi-automatic biology testing laboratory in the Columbus module of the International Space Station. Launched on board the Space Shuttle Atlantis in 2008, the lab allows both astronauts, and scientists back on earth, to understand how weightlessness affects living organisms. Once set going, the experiments are largely automated, freeing up the astronauts to do other things.

One of these tasks includes carefully measuring out liquid nutrients for samples. And  it turns out that the expertise used to develop the machine for doing this, has found other uses back down on earth.

A Belgian biomedical company was looking for help to develop a machine that could automatically run tests for infectious diseases such as HIV and Syphilis.

The types of tests they use are called immunoassays. The test detects disease molecules, known as antigens, which are found in the blood when somebody has an infection.

While the tests can work in lots of different ways, a common approach is to take a thin strip of a special paper, and selectively coat it with antibodies. These are molecules produced by the body as it responds to an infection, and attach strongly to the disease antigens.

A sample from a patient can then be washed over the paper strip. Any disease antigens present in the sample will stick to the antibodies on the surface of the paper. A second, different antibody is then washed over the strip again, which sticks to the other side of the antigen, forming a kind of sandwich.

Attached to this second antibody is an enzyme. The strip is finally washed in another chemical which is broken down by this enzyme producing a coloured dye, which is then visible to the human eye.

The end result is a paper strip with lines that change colour depending on whether the disease is present or not. It’s a similar principle to how pregnancy tests work.

However, the process of running the test can be pretty laborious – it relies upon washing precise quantities of different liquids at different times over the strips. The Belgian biomedical company was trying to work out how to build a machine that could run these tests automatically, a few at a time. It ended up working with the engineers responsible for developing part of the automated tests on the space station’s biolab, who used the same tech and know how to produce an automatic testing machine, freeing up lab scientists to do get more done.

So that’s how experiments designed to test the impact of microgravity on organisms in space, led to automated testing for infectious diseases back on earth.