A zwitterion is a molecule that contains both positively and negatively charged functional groups, and the net charge of the entire molecule is zero. Amino acids are the best-known examples of zwitterions. They contain an amine group (basic) and a carboxyl group (acidic).
Definition of Zwitterion
![Asparagine chemical structure](https://cdn.statically.io/img/www.thoughtco.com/thmb/Jx73d1a67AslaJnhTXHKppRQyvo=/1500x0/filters:no_upscale():max_bytes(150000):strip_icc()/GettyImages-1133862746-6d237f99d0074cd3a72abced03e6706f.jpg)
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By
Anne Marie Helmenstine, Ph.D.
Chemistry Expert
- Ph.D., Biomedical Sciences, University of Tennessee at Knoxville
- B.A., Physics and Mathematics, Hastings College
Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels.
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Updated on March 22, 2019