Carolyn R. Bertozzi

Carolyn R. Bertozzi
Born	10/10/1966
Birthplace	Boston, Massachusetts, United States
Nationality	American
Occupation	Chemist, professor
Employer	Stanford University
Known for	Bioorthogonal chemistry, click chemistry
Education	Ph.D. in Chemistry (University of California, Berkeley)
Awards	Nobel Prize in Chemistry (2022), AACR Award for Outstanding Achievement in Chemistry in Cancer Research (2023), Royal Society of Chemistry Honorary Fellowship (2026)

Carolyn Ruth Bertozzi is an American chemist and professor at Stanford University whose pioneering work in bioorthogonal chemistry and click chemistry has reshaped the landscape of chemical biology and opened new frontiers in the treatment and understanding of disease. Born on October 10, 1966, in Boston, Massachusetts, Bertozzi developed a class of chemical reactions that can take place inside living organisms without disrupting normal biological processes — a breakthrough that earned her a share of the 2022 Nobel Prize in Chemistry alongside Morten Meldal and K. Barry Sharpless. With this honor, Bertozzi became one of only a handful of women to receive the Nobel Prize in Chemistry. Her research has had profound implications for drug development, diagnostics, and the fundamental understanding of cellular biology. Beyond her academic contributions, Bertozzi has served on the boards of major pharmaceutical companies and co-founded multiple biotechnology ventures. She holds the Anne T. and Robert M. Bass Professorship in the School of Humanities and Sciences at Stanford University, with additional appointments in the departments of Chemistry and Chemical & Systems Biology, and serves as an investigator of the Howard Hughes Medical Institute.

Early Life

Carolyn Ruth Bertozzi was born on October 10, 1966, in Boston, Massachusetts. She grew up in the greater Boston area in a family that encouraged intellectual curiosity and scientific exploration. Her father was a nuclear physics professor at the Massachusetts Institute of Technology, providing an environment steeped in scientific inquiry from an early age. Bertozzi has spoken publicly about how growing up in an academically oriented household influenced her eventual pursuit of the sciences.

As a young student, Bertozzi showed aptitude in both the sciences and the arts. She was an accomplished keyboard player and had a strong interest in music during her formative years. This combination of artistic and analytical interests would later inform her creative approach to chemical problem-solving. During her high school years, Bertozzi attended a school in the Boston suburbs where she excelled academically, particularly in mathematics and the natural sciences.

Bertozzi has described her early fascination with the molecular world as something that developed gradually rather than through a single defining moment. Her exposure to the culture of research through her father's academic career gave her familiarity with the rhythms and rewards of scientific work long before she entered a laboratory herself.

Education

Bertozzi pursued her undergraduate studies at Harvard University, where she received a Bachelor of Arts degree in chemistry. At Harvard, she was exposed to a rigorous curriculum in the chemical sciences and began to develop the intellectual framework that would guide her later research. Her undergraduate experience solidified her commitment to pursuing chemistry at the highest level.

Following her time at Harvard, Bertozzi enrolled in the doctoral program in chemistry at the University of California, Berkeley, where she earned her Ph.D. Her graduate research focused on organic chemistry and began to lay the groundwork for her later innovations in chemical biology. The interdisciplinary environment at Berkeley proved formative, exposing Bertozzi to the interface between chemistry and biology that would become the central focus of her career.

After completing her doctorate, Bertozzi conducted postdoctoral research at the University of California, San Francisco, where she worked in the laboratory of immunologist and cell biologist. This postdoctoral period was critical in shifting her research focus toward the application of chemistry to biological systems, particularly the study of cell-surface carbohydrates known as glycans.

Career

Early Academic Career at UC Berkeley

Bertozzi began her independent academic career as a faculty member at the University of California, Berkeley, where she was appointed as an assistant professor in the Department of Chemistry. At Berkeley, she rapidly established herself as one of the most innovative young scientists in the field of chemical biology. Her research group began to explore the chemical modification of cell-surface glycans — complex sugar molecules that play essential roles in cell communication, immune recognition, and disease processes.

During her time at Berkeley, Bertozzi developed the concept of bioorthogonal chemistry, a term she coined to describe chemical reactions that can occur inside living systems without interfering with native biochemical processes. This represented a fundamental conceptual advance: prior to Bertozzi's work, the tools available to chemists for studying biological molecules in their native environments were severely limited. Bioorthogonal reactions provided a way to tag, track, and manipulate specific molecules within living cells and organisms, opening entirely new avenues of biological investigation.

One of Bertozzi's most significant early contributions was the development of the Staudinger ligation, a bioorthogonal reaction adapted from a classic organic chemistry transformation. This reaction allowed researchers to selectively modify azide-bearing molecules on cell surfaces under physiological conditions — a feat that had not previously been achieved. The Staudinger ligation demonstrated that it was possible to perform precise chemical transformations in the complex environment of a living cell, and it served as a proof of concept for the broader field of bioorthogonal chemistry.

At Berkeley, Bertozzi also became a Howard Hughes Medical Institute investigator, a prestigious appointment that provided long-term funding and support for her research program. She rose through the academic ranks to become a full professor and was recognized as one of the leading figures in the emerging discipline of chemical biology.

Move to Stanford University

Bertozzi joined the faculty of Stanford University, where she holds the Anne T. and Robert M. Bass Professorship in the School of Humanities and Sciences. At Stanford, she continued to expand the scope of bioorthogonal chemistry and its applications. Her laboratory developed new classes of bioorthogonal reactions, including strain-promoted azide-alkyne cycloadditions, which further broadened the toolkit available to researchers studying biological processes in living systems.

At Stanford, Bertozzi's research program has addressed a wide range of biological questions, with particular emphasis on the roles of glycans in health and disease. Glycans are among the most complex and least understood classes of biological molecules, and Bertozzi's chemical tools have been instrumental in elucidating their functions. Her group has made significant contributions to understanding how glycans influence immune cell behavior, cancer progression, and infectious disease.

A major focus of Bertozzi's recent work at Stanford has been the study of how cancer cells exploit glycan biology to evade the immune system. Her research has revealed that certain glycans on tumor cell surfaces interact with immune checkpoint receptors, effectively suppressing the immune response against tumors. This discovery has implications for the development of new cancer immunotherapies, as targeting these glycan-mediated interactions could enhance the ability of the immune system to recognize and destroy cancer cells.

Bioorthogonal Chemistry and Click Chemistry

The field of click chemistry, originally developed by K. Barry Sharpless and Morten Meldal, involves a set of chemical reactions designed to be fast, reliable, and selective. Bertozzi's contribution was to extend the principles of click chemistry into living systems through the development of bioorthogonal reactions — reactions that are not only efficient and selective but also compatible with the complex chemical environment of living organisms.

Bertozzi's copper-free click chemistry was a particularly important advance. The original click chemistry reactions developed by Sharpless typically required a copper catalyst, which is toxic to living cells. Bertozzi devised strain-promoted variants that proceeded without any metal catalyst, making them safe for use in living organisms. These copper-free reactions have been adopted by researchers worldwide and are now standard tools in chemical biology, molecular imaging, drug delivery, and materials science.

The impact of bioorthogonal chemistry has extended well beyond basic research. The approach has been applied in the development of new diagnostic methods, including techniques for imaging specific molecules in living tissues. It has also been used in the design of targeted drug delivery systems, where therapeutic agents are selectively released at specific sites within the body. The versatility and broad applicability of bioorthogonal chemistry have made it one of the most influential developments in modern chemistry.

Biotechnology Ventures

In addition to her academic career, Bertozzi has been active in translating her research into commercial applications. She co-founded several biotechnology companies aimed at developing new therapies and diagnostic tools based on glycan biology and bioorthogonal chemistry.

Among the companies associated with Bertozzi is Palleon Pharmaceuticals (now InterVenn Biosciences and other ventures), which focuses on developing glycan-targeted therapies for cancer. These companies represent efforts to bring the insights of Bertozzi's basic research to bear on clinical problems, particularly in oncology and immunology.

Bertozzi's entrepreneurial activities reflect a broader trend in academic chemistry and biology, in which fundamental discoveries are increasingly being translated into new medicines and technologies through startup companies and partnerships with the pharmaceutical industry.

Corporate Board Service

Bertozzi has served on the board of directors of Eli Lilly and Company, one of the world's largest pharmaceutical companies. In December 2025, Eli Lilly announced that Bertozzi had been elected as a returning member of its board of directors. The announcement described Bertozzi's return to the Lilly board, indicating that she had previously served in this capacity before stepping away and then being re-elected.

Her appointment to the board of a major pharmaceutical company underscores the significance of her scientific contributions to the pharmaceutical and biotechnology industries. Board service at companies like Eli Lilly provides a platform for influencing research priorities and corporate strategy at the intersection of academic science and drug development.

Personal Life

Bertozzi is openly gay and has been a visible figure within the LGBTQ+ community in science. She has spoken about the importance of representation and inclusion in the sciences, and her visibility as an openly gay Nobel laureate has been noted in media coverage. Bertozzi has emphasized the value of creating welcoming environments in research institutions for scientists of all backgrounds.

Outside of her research, Bertozzi has maintained her interest in music. She played keyboards in a band during her college years and has referenced the parallels between creativity in music and in science. Her multifaceted interests have contributed to a public persona that extends beyond the typical image of a laboratory scientist.

Bertozzi resides in the San Francisco Bay Area, where she is affiliated with Stanford University. She has been described by colleagues and students as an energetic and engaged mentor who takes an active role in the training and development of the next generation of scientists.

Recognition

Nobel Prize in Chemistry

In October 2022, the Royal Swedish Academy of Sciences awarded the Nobel Prize in Chemistry jointly to Carolyn R. Bertozzi, Morten Meldal, and K. Barry Sharpless "for the development of click chemistry and bioorthogonal chemistry." Bertozzi was recognized specifically for her development of bioorthogonal reactions — click chemistry reactions that function inside living organisms. The prize committee highlighted the transformative impact of these tools on chemistry, biology, and medicine. Bertozzi's affiliation at the time of the award was Stanford University, Stanford, California.

The award of the Nobel Prize brought widespread international attention to bioorthogonal chemistry and its applications. The chemistry community reacted with enthusiasm to the recognition of work that had fundamentally expanded the scope of chemical research.

AACR Award

In March 2023, the American Association for Cancer Research announced that Bertozzi would receive the 2023 AACR Award for Outstanding Achievement in Chemistry in Cancer Research. The award recognized Bertozzi's contributions to the application of chemistry to cancer research, particularly her work on glycan-mediated immune evasion by tumors. The AACR described Bertozzi's research as having opened new approaches to cancer immunotherapy and diagnostics.

Royal Society of Chemistry Honorary Fellowship

In early 2026, the Royal Society of Chemistry announced that it would honor Bertozzi with an Honorary Fellowship, the organization's highest accolade. Bertozzi was named as one of seven individuals to receive the distinction in that year. The Honorary Fellowship recognizes individuals who have made exceptional contributions to the chemical sciences.

Other Honors

Throughout her career, Bertozzi has received numerous other awards and honors from scientific organizations worldwide. She has been elected to the National Academy of Sciences, the American Academy of Arts and Sciences, and the National Academy of Inventors, among other learned societies. Her publication record includes hundreds of peer-reviewed articles, and she has been among the most highly cited chemists in the world.

Legacy

Carolyn R. Bertozzi's contributions to chemistry and biology have had a lasting impact on multiple scientific disciplines. The concept of bioorthogonal chemistry, which she introduced and developed, has become a foundational tool in chemical biology. Thousands of researchers around the world now use bioorthogonal reactions as standard methodology for studying biological processes, developing diagnostics, and creating new therapeutic strategies.

Bertozzi's work has been instrumental in establishing glycobiology — the study of the roles of sugars in biological systems — as a major area of biomedical research. By providing tools to probe glycan function in living systems, her research has helped to reveal the importance of these molecules in immunity, infection, and cancer. The glycan-targeted therapeutic approaches emerging from her laboratory and associated companies represent a new paradigm in drug development that may yield treatments for a range of diseases.

As one of the few women and one of the few openly LGBTQ+ scientists to receive the Nobel Prize, Bertozzi's recognition has had significance beyond the scientific content of her work. Her visibility has contributed to broader conversations about diversity and inclusion in science, and she has served as a role model for scientists from underrepresented groups.

The field of bioorthogonal chemistry that Bertozzi created continues to grow and evolve. New reactions, applications, and methodologies are being developed by research groups around the world, building on the foundation that Bertozzi established. The influence of her work is evident in fields ranging from molecular imaging and drug delivery to synthetic biology and materials science, ensuring that her scientific contributions will shape research for decades to come.