Sugars are attractive building blocks for functional materials because of their high water affinity and diverse biological properties. Incorporating sugars into synthetic polymers can therefore provide materials that combine the processability of polymers with characteristics derived from carbohydrates. However, selective chemical modification of sugars is often challenging because they contain multiple hydroxyl groups with similar reactivities, making it difficult to introduce a polymerizable group at one defined position without multistep synthetic procedures.
One promising alternative is 4-trehalosamine, a microbial metabolite related to trehalose in which one hydroxyl group is replaced by an amino group at the C4 position. Previous studies have demonstrated that 4-trehalosamine is highly resistant to degradation by mammalian trehalase, can be produced by microbial fermentation, and can be readily modified through its chemically distinct amino group. These properties suggested that 4-trehalosamine could serve not only as a stable trehalose analog but also as a versatile starting material for creating new functional molecules.
A joint research team led by Professor Koji Matsuoka of the Graduate School of Science and Engineering, Saitama University, together with researchers at the Institute of Microbial Chemistry (BIKAKEN), set out to exploit the selectively reactive C4 amino group of 4-trehalosamine to create a polymerizable sugar monomer and determine whether it could be incorporated into water-soluble polymers in controllable amounts. The researchers synthesized a 4-trehalosamine-derived acrylamide monomer by introducing a polymerizable group through the amino group and subsequently used the monomer in polymerization reactions, including copolymerization with acrylamide. By varying the monomer composition, they successfully prepared water-soluble polyacrylamides containing adjustable amounts of 4-trehalosamine-derived units.
The study, entitled "A 4-Trehalosamine-Derived Acrylamide Monomer: Synthesis and Preparation of Composition-Tunable Water-Soluble Polyacrylamides," was made available online in Carbohydrate Research on September 19, 2026.
An important feature of the study is that the researchers used the amino group already present at a defined position in 4-trehalosamine as a chemical handle for constructing the polymerizable monomer. This avoids the need to distinguish chemically among the numerous hydroxyl groups of the sugar when introducing the key polymerizable functionality. Furthermore, copolymerization with acrylamide enabled the proportion of 4-trehalosamine-derived units in the resulting water-soluble polymers to be varied. The work therefore establishes a synthetic platform in which both the distinctive properties of 4-trehalosamine and the composition of the polymer can be systematically controlled.
Professor Matsuoka explains the significance of the work: "The amino group of 4-trehalosamine provides a unique handle for selective chemical modification. By converting it into a polymerizable unit, we established a straightforward route to water-soluble glycopolymers with controllable sugar contents."
Looking further ahead, the ability to combine a fermentation-derived, biologically stable trehalose analog with tunable polymer chemistry could support the development of new water-soluble materials in fields where hydration, stabilization, molecular interactions, or interfaces are important. Such applications will require further evaluation of the physicochemical and biological properties of individual polymers, as well as studies of manufacturing and safety.
Professor Matsuoka adds: "We anticipate that this platform will facilitate the rational design of carbohydrate-containing polymers for biotechnology and advanced functional materials. Because 4-trehalosamine can be produced biologically and selectively modified, it may help connect fermentation-derived molecules with functional polymer materials. As interest in bio-based materials continues to grow, this approach may provide new opportunities for developing sustainable functional polymers."
