One end carries a positive charge.
The other carries a negative one.
Chemists call these molecules zwitterions, from the German word meaning ""hybrid."" Instead of behaving like a typical acid or a typical base, they carry both characteristics at the same time.
Nature uses this idea everywhere. Amino acids, the building blocks of proteins, exist largely as zwitterions in our bodies. Other naturally occurring molecules, including taurine and many biological metabolites, share the same remarkable feature.
3-Amino-1-propanesulfonic acid follows this elegant design. Its amino group can carry a positive charge, while its sulfonic acid group remains strongly negative over a wide range of conditions. The result is a molecule that is highly water-soluble, chemically stable, and capable of interacting with many different biological and synthetic systems.
Global Chemical Database