12 Women Scientists Who Shaped STEM History

1903-1994

In 1938, Ruth Ella Moore became the first African American woman to earn her PhD in natural science (bacteriology) from Ohio State University. Her dissertation and subsequent research significantly advanced our understanding of tuberculosis (TB) and the immunology of blood groups. She was also the first Black woman to join the American Society for Microbiology, although Jim Crow laws of the time often restricted her from attending meetings.  

Outside of the lab, Moore was a talented seamstress and fashion designer whose garments are now preserved historically. She created many of her own clothes for daily and special occasion wear.  

How researchers are expanding on Moore’s work today

🔗

Moore was a pioneer in understanding the bacteriology of TB at a time when it was a leading cause of death. Today, the fight against TB has shifted from manual identification to “genomic surveillance,” where scientists use whole genome sequencing (WGS) of TB strains to track transmission, map outbreaks, identify drug resistance, and guide public health response.

In 2022, for example, researchers used Ion Torrent™ next-generation sequencing (NGS) platform technology to report for the first time large-scale chromosomal rearrangements of M. tuberculosis, revealing how genomic “shuffles” contribute to the evolutionary success and drug resistance of modern hyper-virulent strains.

Read more about Dr. Moore

• Biographical Feature: Ruth Ella Moore, Ph.D. (J. Clin Microbiol. 2025)
• Ruth E. Moore: Remarkable Achievements in an Invisible Life (American Society of Microbiologists, 2024)
• See some of Dr. Moore’s original clothing designs in OSU’s Clothes Line blog

1870-1938

Ynés Mexía was a Mexican-American botanist who found her passion for scientific exploration late in life, in her fifties, when she embarked on her first botanical expedition to western Mexico. In her brief 13-year scientific career before her death, she collected over 145,000 plant specimens from Mexico, South America, and Alaska. She discovered 500 new species, several of which were named in her honor – like Mexianthus mexicanus in the sunflower family.  

In pursuit of her specimens, Mexía often travelled solo through treacherous and unmapped terrains, once famously falling off a cliff and riding a balsa raft down the Amazon to get her samples back to safety.  

How researchers are expanding on Mexía‘s work today

🔗

Mexía collected physical specimens to catalog biodiversity. Today’s biologists can now go many levels deeper in understanding the physiology of plants, through the use of molecular analysis.

In a landmark 2009 PNAS paper, researchers established a universal standard process for the DNA barcoding of land plants using a 2-locus combination of the rbcL and matK genes.

Today’s scientists also still utilize historical herbarium samples for genetic analysis. To help extract usable samples from old or degraded tissues samples, researchers have access to technologies like the Thermo Scientific™ MagMAX™ Plant DNA Isolation Kit, which uses magnetic beads to capture highly fragmented DNA.

Researchers recently used MagMAX kits to explore the evolutionary diversity of the Ethiopian cereal staple crop teff; they used germplasm samples collected in the 19^th and 20^th centuries as sourced from a USDA-ARS database.

Read more about Mexía

• 145,000 Plants with Adventuress Ynes Mexia (Library of Congress, 2024)
• Archives Unboxed: Ynes Mexia (California Academy of Sciences, 2014)
• How Finding Rare Plants Saved Ynes Mexia’s Life (Outside Magazine, 2019)

1871-1953

Florence Sabin was a prolific physician and medical scientist whose career changed our understanding of the immune system and transformed public health in the state of Colorado.

As the head of the department of cellular studies at the Rockefeller Institute for Medical Research in New York City, Sabin focused on detailing the origins of the lymphatic system as well as the pathology of tuberculosis. Her work overturned the prevailing medical wisdom of the time by proving that the lymphatic system originated in embryonic veins. She became the first woman to gain membership to the prestigious National Academy of Sciences in 1925, where she would remain the lone female member for 20 years.  

After “retiring” in her sixties, Sabin embarked on a second career in her home state of Colorado as a public health policy advocate. She lobbied tirelessly to pass the “Sabin Health Laws” that modernized the state’s health system by increasing tuberculosis treatment resources and capacity.   

How researchers are expanding on Sabin’s work today

🔗

Sabin discovered that lymphatic vessels arise from veins. Modern oncology research builds on this discovery through the study of cancer lymphangiogenesis—how tumors grow their own lymphatic “highways” to spread to other organs.

This 2023 study uses Invitrogen™ Alexa Fluor™ secondary antibodies to demonstrate that lymphatic drainage—where specialized lymphatic vessels within the bone remove waste, fluid, and inflammatory cells—is a hidden engine of skeletal regeneration. Unblocking lymphatic drainage barriers, the researchers argue, therefore represents a viable new strategy for accelerating bone repair and healing.

Read more about Sabin

• Explore Sabin’s life through multimedia archives at the National Library of Medicine
• Florence Sabin pioneered her way in medical science, then made sure other women could do the same (Smithsonian Magazine, 2018)
• Dr. Florence Rena Sabin (NIH Biography) 
• Lymph, there it is: Florence Sabin, pioneer woman of medical research (Women in Science Archive, 2023)

1863-1954

Anna Wessels Williams worked as a volunteer at the country’s first municipal diagnostic laboratory at the New York City Department of Health. In response to a diphtheria epidemic among children, Williams isolated a strain of the bacteria (now called Park-Williams No. 8 or PW8) to enable large-scale production of an antitoxin.  

In later years, her research interests shifted to the rabies virus; she developed small quantities of a vaccine from culture and helped to spark wider interest in vaccine research in the U.S. By the end of the century, she was able to create an effective rabies vaccine for mass production.  

Williams also studied under fellow medical pioneers Elizabeth Blackwell and Mary Putnam Jacobi.    

How researchers are expanding on Williams’ work today

🔗🔗

Williams pioneered the isolation of stable bacterial strains for the diphtheria vaccine and proved that vaccines could be mass-produced with consistent quality. Modern vaccinology builds on her work with the use of specialized “serum-free media” to grow vaccine-producing cells in massive quantities without the risk of contamination from animal-derived proteins.

In this Clinical and Experimental Vaccine Research publication from 2020, Korean researchers used Gibco™ OptiPRO™ SFM to adapt kidney-derived Vero cells to suspension culture. Suspension culture significantly increased yields of adenovirus type 5 (Ad5) versus adherent culture, paving the way for more efficient vaccine production at scale. 

Read more about Williams

• Anne Wessels Williams: Infectious Disease Pioneer and Public Health Advocate (American Association of Immunologists, 2012)
• Browse Williams’ student manual about microbiology from 1910

1881-1975

Born on a Pennsylvania farm in 1881, Alice Evans attended a one-room schoolhouse before becoming a teacher – the only profession open to women. Finding the work to be boring, she pivoted to agriculture and bacteriology after taking a free course for rural teachers at Cornell University meant to encourage their students to love science and nature. Evans was so committed to her work that she learned German in order to read bacteriology research reports.  

After her studies, Evans landed at the U.S. Department of Agriculture in the Bureau of Animal Industry’s Dairy Division. While there, she discovered that the bacteria causing brucellosis in cows (Bacillus abortus) could cause a debilitating disease in humans called undulant fever or brucellosis, challenging the belief that bovine diseases didn’t affect people.  

Her findings were initially ridiculed by male scientists and the dairy industry, but Evans persisted and eventually moved the industry to adopt mandatory milk pasteurization in a move that saved countless lives. Her success led her to become the first female president of the Society of American Bacteriologists (now the American Society of Microbiology).  

How researchers are expanding on Evans’ work today

🔗

Evans faced immense skepticism from the scientific community and public when she claimed that raw milk was dangerous.

A modern study analyzed 200 samples of artisanal raw milk, ricotta, and other fresh cheeses from Tunisia using Applied Biosystems™ TaqMan™-based real-time PCR and qPCR and found the brucellosis-causing Brucella spp. in 75%. Brucellosis is a serious and often chronic bacterial infection that causes prolonged flu-like symptoms and joint pain; the infection can also trigger long-term complications like arthritis, heart damage or chronic fatigue.

Aside from brucellosis, we now know that raw milk consumption carries risk of many foodborne illnesses and parasites like campylobacter, salmonella, E. coli, listeria, and more.

Read more about Dr. Moore

• Alice Evans, a pioneer for women in microbiology (American Society for Microbiology, 2023)
• Explore the Alice C. Evans papers in the National Library of Medicine archives
• A first-hand account from Alice Evans’ memoirs about her experiences during the 1918 flu pandemic (NIH Catalyst)

1857-1945

Ida Henrietta Hyde was a Jewish-American physiologist best known for inventing the micro-electrode, a device small enough to stimulate a single cell without destroying it.  

The tool revolutionized neurophysiology, but Hyde’s path to science was not easy. Despite receiving a B.A. degree from Cornell in just 3 years and later studying under the tutelage of Nobel Laureate geneticist Thomas Hunt Morgan at Bryn Mawr College, she faced many obstacles to receiving her PhD.  

After a researcher invited her to study with him in Germany, Hyde became the first woman ever to petition Germany’s government to receive an advanced degree in natural science. At the University of Heidelberg, she had to fight to be allowed to take the PhD exam, was not allowed to attend some lectures, and often had to study from the notes of male students; despite faculty and systemic opposition, she graduated with honors.  

Recognizing the barriers that she and others like her faced, Hyde cemented her legacy by endowing the Ida H. Hyde Woman’s International Fellowship to help other women pursue science careers.  

How researchers are expanding on Hyde’s work today

🔗

Ida Henrietta Hyde invented the microelectrode in 1921 using mercury conduction and a hand-pulled glass pipette. Her device physically punctured the cell wall without destroying the cell. Today’s machine-produced microelectrodes remain a foundation of modern electrophysiology, where new evolutions of her design are applied in several ways:

• Intracellular recording: Scientists use advanced versions of her glass micropipettes to measure the resting potential of cells—essential for understanding how neurons and muscle cells communicate.
• Patch clamping: This Nobel Prize-winning technique evolved directly from microelectrode technology. IT allows researchers to study single ion channels in a cell membrane, which is crucial for developing drugs for heart disease, epilepsy, and pain management.
• Microinjection: Because the electrode is hollow, it is still used to inject genetic material, dyes, or drugs into a single cell with microscopic precision—a process used heavily in IVF and genetic engineering.

Today’s researchers can also now visualize electrical signals non-invasively through fluorescent calcium imaging. This group of German researchers, for example, applied calcium imaging techniques to measure immune signaling in the gut. The team used the Ca²⁺ sensitive green dye Invitrogen™ Fluo-4 AM. The results revealed the first direct cellular evidence of two-way signaling between immune mast cells and neurons in the human intestine, a key mechanism in the so-called neuroimmune axis.

Read more about Hyde

• Ida Henrietta Hyde and the micro-electrode (IEEE History Center, 2021)
• Ida Henrietta Hyde biography (Jewish Women’s Archive)
• Read Hyde’s paper about blood flow in the heart published in the first issue of the American Journal of Physiology in 1898

1866-1943

Before she wrote The Tale of Peter Rabbit, Potter was a serious scientist who studied mycology and was one of the first researchers in Britain to successfully germinate fungal spores. Potter’s detailed and scientifically accurate illustrations of microscope spores were groundbreaking for the time, though her work as a woman was often dismissed by the established community.  

After her paper on spore germination was rejected by the all-male Linnean Society in 1897, she pivoted to writing and illustrating children’s books, leaving science behind but retaining her keen eye for nature.   

How researchers are expanding on Potter’s work today

🔗

Potter’s scientific legacy is built on her precise morphological observation and illustration of fungi.  

Modern mycologists today can use fluorescent imaging to clarify molecular and genetic morphological details. Using the high-resolution Invitrogen™ EVOS™ M5000 Imaging System and Invitrogen™ MitoSOX™ Red, nanomedical researchers in China explored the therapeutic potential of a novel metal-organic framework called ZIF-90 for vision-threatening corneal infection fungal keratitis. ZIF-90 demonstrated anti-disease effects by compromising the fungal cell wall and targeting mitochondrial reactive oxygen species (mtROS) to reduce inflammatory response.

Read more about Potter:

• Beatrix Potter (Linnean Society of London)
• The Tale of Beatrix Potter (Public Domain Review, 2014)
• Explore the Armitt Museum’s Beatrix Potter collection of fungi illustrations and “Under the Microscope” exhibit

1794-1871

French dressmaker-turned-marine biologist Jeanne Villepreux-Power invented the world’s first glass aquarium in 1832 to observe the aquatic organism known as the paper nautilus or argonaut – a type of octopus that encases itself in a delicate, buoyant shell to float and nurse eggs. Through her aquarium setup, Villepreux-Power discovered that the paper nautilus produces its own shell rather than acquiring it from the environment.  

Though she once made a wedding gown for a Sicilian princess, Villepreux-Power’s legacy lies in her transformation of marine biology with the aquarium as well as her early contributions to sustainable aquaculture practices.   

How researchers are expanding on Villepreux-Power’s work today

🔗

Jeanne Villepreux-Power invented the aquarium to observe marine life in real-time.

Today’s scientists don’t necessarily even need to see aquatic creatures in order to know they are there, thanks to the discovery of environmental DNA (eDNA). eDNA metabarcoding using next-generation sequencing (NGS) tools like the Ion Torrent sequencer allows researchers to identify many species in a large body of water by sampling the water and analyzing the trace DNA within. eDNA metabarcoding offers a route to monitoring marine and freshwater biodiversity for basic research and ecological protection.

eDNA studies can, for example, detect the early presence of aquatic invasive species like zebra mussels or help coastal communities understand the biodiversity of their marine systems. This is especially true when studies tap into regional networks of citizen scientists for broader sample collection.

Read more about Dr. Moore

• The seamstress who solved the ancient mystery of the argonaut, pioneered the aquarium, and laid the groundwork for the study of octopus intelligence (The Marginalian, 2022)
• “The Lady and the Octopus: How Jeanne Villepreux-Power Invented Aquariums” (Aquarium of the Pacific recorded lecture, 2024)

1904-1960

Ruby Hirose was a Japanese-American biochemist and bacteriologist working on topics in blood clotting, allergies, and cancer. Her research on serums and antitoxins contributed significantly to the development of the polio vaccine. She also made major strides in treating allergies, specifically by finding ways to improve pollen extracts used to desensitize hay fever sufferers.  

While Hirose was making national headlines for her chemistry contributions, her brother, sister, and father were forcibly incarcerated in internment camps during WWII –a stark contrast between her professional recognition and personal reality.   

How researchers are expanding on Hirose’s work today

🔗

In the 1930s, Dr. Hirose conducted foundational research on the purification of prothrombin and its conversion into the active enzyme thrombin.

Today, thrombin is no longer just studied for its role in blood clotting; it is used in research labs as a primary “molecular switch” for studies of a family of G-protein coupled receptors called protease-activated receptors (PARs). PARs are key drug targets for cardiovascular conditions.

Commercial Invitrogen™ human recombinant thrombin proteins enable research focused on preclinical questions in coagulation, cell signaling, platelet activation, diagnostic assay development and more.

Read more about Hirose

• Ruby Hirose: A Japanese-American researcher who helped understand blood clotting and immune reactions (History of Vaccines, 2023)
• Five fast facts about Dr. Ruby Hirose (Department of Energy, 2017)

1898-1997

Katherine Esau was a German-American plant biologist whose textbook Plant Anatomy (1953) became seminal in the field and served as the standard university textbook for decades.  

Esau was a pioneer in using the electron microscope to study plants, discovering how crop-devastating diseases–like the curly top virus in sugarbeets and tobacco—move and spread through phloem tissue. Despite using state-of-the-art technology and publishing field-shifting results that eventually earned her the National Medal of Science.

Despite her outsized impact on the field and use of state-of-the-art methods throughout her career, Esau maintained a humble outlook. She told an oral historian that she had no idea what had impressed the National Medal committee enough to select her; when asked what it was like to use an electron microscope for the first time, she said, “Well, you know, I’m not such an impressionable person. I take my matters step-by-step as they go. You expect me to be ‘Ahhh, Ooohhh.’ I’m not like that at all. I’m a very mundane person.” 

She remained active in research well into her 90’s, publishing her last paper at age 93.   

How researchers are expanding on Esau’s work today

🔗

Esau wrote the definitive text on the phloem and was an early user of cryo-electron microscopy. Today’s structural biologists continue to use cryo-EM to examine phloem receptors at the atomic level, illustrating in increasing detail the long-distance signaling pathways that Esau described in histology.

While plants lack a brain, they use glutamate receptor-like channels (GLRs) to communicate; these proteins are homologs of the receptors that trigger neurons in the human brain. In plants, GLRs sense environmental stress and send long-distance electrical signals through the phloem vasculature to coordinate systemic responses like wound healing.

A recent study in Molecular Cell presented the first-ever high-resolution plant GLR architecture map using advanced proteomics and purification techniques to validate their model in Arabidopsis thaliana. The team used Invitrogen™ Dynabeads™ magnetic bead technology and Thermo Scientific™ EASY-Spray™ PepMap™ nano-LC columns to isolate and separate pure biotinylated complexes ahead of sensitive protein mapping analysis. They also used an Thermo Scientific™ Orbitrap™ Fusion Tribrid mass spectrometer to analyze cross-linked peptides and help inform an accurate 3D model. Finally, the group captured nearly 12,000 high-resolution cryo-EM images on the Thermo Scientific™ Titan™ Krios™ transmission electron microscope.

Read more about Esau

🔗

• Katherine Esau (American Philosophical Society, 2023)
• National Academy of Sciences full biography (1999)
• Katherine Esau Fellowship (UC Davis Plant Biology)

1896-1980

May Edward Chinn was a Black physician from New York City. The daughter of a former slave and indigenous mother, Chinn was forced to drop out of high school due to poverty. Still, she took the entrance exam to Columbia Teachers College to study music before switching to the sciences at the encouragement of her bacteriology professor.  

While barred from practicing in many hospitals due to her race, Chinn found a meaningful research collaboration studying cytology for cancer detection with George Papanicolaou, inventor of the pap smear, at New York’s Strang Cancer Clinic. From this work, she became a passionate advocate for early cancer screening. In her own private practice, Chinn provided care for Black patients who could otherwise not receive treatment in segregated facilities.  

Despite dedicating her career to science, Chinn never lost her early interest in music and continued to teach piano lessons and serve as an accompanist to fellow musicians – including Paul Robeson – throughout her life.   

How researchers are expanding on Dr. Chinn’s work today

🔗

Dr. May Chinn pushed for early cancer screening via Pap smears. Today, her legacy of early detection continues through liquid biopsy methods detecting genetic cancer fragments (through circulating tumor DNA or ctDNA and cell-free DNA or cfDNA).

To better understand tumor progression over time, researchers like Dr. Karen Page, the lead for next-generation sequencing (NGS) in Professor Jacqui Shaw’s Lab at the UK’s Leicester Cancer Research Center, have invested decades of work into the potential of a non-invasive ‘liquid biopsy’ for longitudinal and comprehensive study of the disease process. Through a simple blood draw, clinicians and researchers could gain insight into tumors anywhere in the body – even those not yet detectable by imaging.

Page and her colleagues in the Shaw Lab aim to standardize this potentially field-shifting process so that it can make the wider jump from research to clinic and more universal access.

Read more about Dr. Chinn

• NIH biography
• The extraordinary life and work of May Edward Chinn (NYU Alumni Magazine, 2022)
• May Edward Chinn: a pioneer of early cancer detection (The Lancet, 2023)

1904-1980

Flemmie Pansy Kittrell was the first Black woman to graduate from Cornell University with a PhD, and the first Black woman in the nation to earn one in home economics. Kittrell’s doctoral work focused on the epidemic of “hidden hunger”—malnutrition in people who appear well-fed—that was influencing high Black mortality rates in the 1930s.  

Throughout her career, Kittrell transformed the home economics, child development, and nutrition fields with insights on adult and infant nutrition, Black infant mortality, and the importance of preschool enrichment. She established Howard University’s Nursery School, which functioned as a laboratory for early childhood education study and the model of early childhood research nationally.  

Her work was foundational to the creation of the Head Start program in 1965, which to this day provides early childhood development services including education, health, nutrition and family support to low-income families. Internationally, her work also led to major changes in the agricultural practices of countries like Liberia to address widespread vitamin deficiencies.    

How researchers are expanding on Kittrell’s work today

🔗

Dr. Flemmie Kittrell was the first to identify a phenomenon she named “hidden hunger”—dangerous malnutrition in seemingly well-fed people, caused by a lack of access not to calories but to essential micronutrients. Her work led to significant changes in the agricultural practices of African nations like Liberia.

In many underdeveloped countries today, nutritional deficiency remains a thread along with endemic diseases like malaria. Recent research has shown that nutritional intake can actually impact malaria treatment.

Gibco™ Human Plasma-like Medium (HPLM) is a cell culture medium developed by Whitehead Institute/MIT postdoc Jason R. Cantor in 2017. Where most media provide micronutrients in artificial abundance, HPLM simulates the natural, nutrient-limited metabolic profile of human blood plasma. In this way, HPLM can help researchers reproduce the environment of a human host suffering from malnutrition.

When malaria parasites are “starved” of certain nutrients in HPLM, they enter a dormant state that makes them resistant to the anti-malarial drug Artemisinin (developed by another woman in STEM history, Tu YouYou.)

Read more about Dr. Kittrell

• Remembering ‘a fighter, and an activist for the hungry and poor’ (Cornell University Alumni Magazine, 2025)
• Globetrotting Black nutritionist Flemmie P. Kittrell revolutionized early childhood education and illuminated ‘hidden hunger’ (The Conversation, 2023)
• How the daughter of sharecroppers revolutionized preschoolers’ health (Scientific American, 2023)