nonsulfated

Nonsulfated describes a molecule that lacks sulfate groups or ester sulfo groups. It is used as a general descriptor in chemistry, biochemistry, and related fields to distinguish a compound from its sulfated derivatives, which may differ in charge, solubility, and biological interactions.

In biology and pharmacology, sulfation is a common modification that can alter solubility, transport, receptor binding, and excretion. Nonsulfated forms may have different pharmacokinetic and pharmacodynamic properties compared with their sulfated counterparts. For proteins and small molecules, the presence or absence of sulfate groups can influence stability, localization, and activity.

In the context of glycosaminoglycans (GAGs), nonsulfated refers to GAGs that lack ester sulfate groups. Hyaluronic acid is a prominent example of a nonsulfated GAG, contributing to its high negative charge density and distinctive physical properties without sulfates. In contrast, sulfated GAGs such as chondroitin sulfate, dermatan sulfate, keratan sulfate, and heparan sulfate carry sulfate esters that affect their conformation and interactions with proteins.

Common examples across disciplines include nonsulfated steroid hormones (the parent steroids) versus their sulfated forms (for example, DHEA vs DHEA-S), and nonsulfated polymers or drugs that are not modified by sulfate conjugation. Overall, the term highlights the chemical absence of sulfate functionality and its implications for solubility, polarity, and biological behavior.