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A cure for leprosy eluded humans for thousands of years, until the pioneering chemistry work of Alice Ball. With her treatment, patients recovered enough to be discharged from the hospital by the hundreds.

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Go to to learn how you can take your STEM skills to the next level this year! [♪ INTRO]. Leprosy is a disease that has affected humanity for thousands of years, going back to at least 2000 BCE.

It inflicts painful skin lesions, and the lack of a cure has led people with leprosy to be shunned and isolated throughout history, even up until the turn of the 20th century. It’s sometimes referred to as Hansen’s disease, after the scientist who discovered its cause, the bacterium Mycobacterium leprae, in 1873. But even that didn’t lead to a reliable treatment right away.

A cure might have had to wait until the widespread availability of antibiotics in the 1940s, if it weren’t for the pioneering chemistry work of Alice Ball. Alice Augusta Ball was born in Seattle in 1892. Her grandfather, James Presley Ball, Sr., is thought to have been one of the first ever Black photographers.

Photography at the time was an intricate task, requiring a lot of chemicals to develop the photos. Though we don’t know for sure, it’s possible that observing her grandfather at work led young Alice to develop an interest in chemistry. In 1902, when Alice was eight, the family moved to Honolulu in an attempt to improve her grandfather’s poor health.

When he passed away in 1904, Ball returned to Seattle, where she studied both pharmaceutical chemistry and pharmacy at the University of Washington. She returned to Hawai’i for graduate school and became both the first woman and the first African-American to earn a master’s degree in chemistry from what is now the University of Hawai’i. For her thesis, she developed ways to extract active ingredients from medicinal plants.

She was also one of the first Black women ever to earn an advanced degree in chemistry. After Ball graduated, she started working with Dr. Harry Hollmann, a researcher who was studying chaulmoogra oil.

At the time, this was one of the few treatments available for leprosy. The oil, derived from the chaulmoogra tree, has antibacterial properties. In fact, it’s been used in Indian and Chinese traditional medicine to treat skin conditions for centuries.

But while you could slather it directly on a person’s skin, it wasn’t especially reliable. Some people tried to make the most use of the oil’s antibacterial properties by injecting it directly into the patients, but the oil was too thick to be absorbed by the body, causing painful blisters to erupt on the patient’s skin. Which was kind of the problem in the first place.

Hollmann wanted to improve treatments for leprosy patients, but he needed an expert in natural product chemistry, which is why he recruited Ball. During her work with Hollmann, Ball developed a technique to make chaulmoogra oil injectable by isolating its active ingredients. Ball’s method first started with saponification of the oil.

Saponification is the same chemical process used to turn fat and oil into soap, with an alcohol as a byproduct. It involves heating the fat and oil with a strong base, in this case, potassium hydroxide. Saponifying the oil made it possible to purify its active ingredients in the form of fatty acid salts; basically a long oily molecule paired with a positively charged potassium ion.

A few more chemical steps converted these into ethyl esters, molecules that were more water-soluble than they had been in their oil form. And making them soluble made them easier for our bodies to use, which is exactly what you want in a medicine. So the end result was a form of chaulmoogra oil that retained its bacteria-fighting abilities, while being way easier to administer to patients.

Ball’s treatment worked. Her ethyl esters were both safer and more effective than any other leprosy treatment available at the time. And when her method was used, leprosy patients recovered enough to be discharged from the hospital by the hundreds.

Sadly, Ball passed away in 1916, before she could publish her results. She was only 24 years old. Her colleague, Arthur Dean, published her work as his own, claiming to have made improvements to the process and not mentioning her name.

Dean’s claim went unchallenged until Ball’s former colleague Harry Hollmann published a paper that credited her with the technique: Ball’s method. Hollmann also disputed that Dean’s method was any improvement at all over Ball’s original. Even after that, however, it took some time for Ball to receive the recognition she deserved.

In the year 2000, though, the University of Hawai’i officially honored her with a plaque next to the school’s only chaulmoogra tree. And in 2007, Ball was posthumously awarded the University of Hawai’i’s medal of distinction, its highest honor. Although Alice Ball died young, her development of the Ball method allowed people afflicted with leprosy to recover and return to their families.

And her treatment remained the dominant method for treating leprosy until the 1940s, when antibiotics became widely available. Regrettably, we know very little of her personal life: why she became a chemist, and what more she hoped to accomplish. But we do have a record of Alice Ball’s incredible work, and her legacy as one of the first Black women in chemistry.

Now, all scientists, especially the pioneers, need a working grasp of statistics. Stats help us draw conclusions when our data is limited, and it’s always limited. If you want to build that foundation for yourself, you might be interested in Brilliant’s brand new Statistics course, which will teach you to make judgments based on limited information.

Brilliant lets you learn at your own pace without tests or grades, and if you make a mistake, there’s always an explanation to help you out. So if you’re ready to get smarter, you can check out. to get 20% off an annual premium subscription. [♪ OUTRO].