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The caption for the article’s photograph reads, “A $1 marker pen designed by Johns Hopkins students is filled with enough reagent to administer up to 400 prenatal disease tests.” The article, breaking down the device, goes on:

Every year, a combined 6.3 million pregnant women and newborns die from pregnancy and childbirth complications. Ninety-nine percent of maternal deaths occur in developing countries where most women receive little, if any, prenatal care. So Monagle, now a graduate student at the university’s Center for Bioengineering Innovation and Design—along with his engineering classmates Maxim Budyansky, Sherri Hall, Matthew Means, Shishira Nagesh Mary O’Grady, Peter Truskey and James Waring—designed a pen that can identify prenatal diseases early, accurately and far more costeffectively than other methods.

In the U.S., the most common way for doctors to screen expectant mothers for preeclampsia and related complications is with a 50-cent dipstick. But in developing countries, dipsticks are too expensive for widespread use. With their marker, Monagle and his colleagues created a prenatal test that’s simple enough to be used and interpreted by anyone and costs only a third of a cent per use.

That night in his lab, Monagle was testing for preeclampsia and related disorders. The condition causes 76,000 maternal and 500,000 infant deaths every year, yet it’s easily treatable if detected early. He drew a yellow line on a piece of filter paper with the pen and squeezed a drop of urine from one of the vials onto the paper. The test strip turned cobalt blue. Chemical reagents he had mixed in the marker’s “ink” (a liquid solution containing a buffer that the students formulated) had reacted with high levels of protein in the urine, a sure sign of preeclampsia.

We have been finding that a majority of innovations across the globe are focused in the areas of medicine and medical care. It’s not surprising when one considers the amount of shear brainpower existing in those fields.

medical team

Our next invention is not in those fields. It is a fairly different field but no less interesting or innovative: sewage. Here is a video breaking down Namon Nassef’s Zero Liquid Discharge Sewage Elimination System: