The disclosure relates to poly alpha-1,6-glucan derivatives comprising poly alpha-1,6-glucan substituted with at least one organic group linked to the poly alpha-1,6-glucan through a linkage moiety selected from ether, sulfonyl, carbonate, or carbamoyl/carbamate, and having a degree of substitution of about 0.001 to about 3.0. The poly alpha-1,6-glucan comprises a backbone of glucose monomer units wherein greater than or equal to 40% of the glucose monomer units are linked via alpha-1,6 glycosidic linkages, and optionally at least 5% of the backbone glucose monomer units have branches via alpha-1,2 and/or alpha-1,3 glycosidic linkages. Compositions comprising a poly alpha-1,6-glucan derivative can be useful in various applications.

Provided are methods of attaching a mannose-binding C-type lectin receptor targeting moiety to a polymeric carbohydrate backbone using an amide linkage. The amide linkage may be found between a leash, such as an amine terminated leash, and the mannose-binding C-type lectin receptor targeting moieties. The compounds and compositions disclosed utilizing the amide linkage provide for highly stable compounds with a significant reduction in loss of mannose-binding C-type lectin receptor targeting moieties from the polymeric carbohydrate backbone.

Compositions comprising a reaction product of a saccharide polymer and a fatty acid or a fatty ester may be obtained in an aqueous phase in the presence of a hydroxide base and a neutral surfactant, the saccharide polymer comprising a dextran, a dextrin compound, or any combination thereof. The neutral surfactant may comprise at least one compound having a structure of ##STR00001##
in which R.sup.1 is a saturated or unsaturated hydrocarbyl group having about 8 to about 30 carbon atoms; R.sup.2 is C.sub.1-C.sub.4 optionally branched alkyl, CH.sub.2OH, CH.sub.2O(CH.sub.2CH.sub.2O).sub.xCH.sub.2CH.sub.2OH (x is 0 or a positive integer), CH(OH)CH.sub.2OH, CO.sub.2H, or CH.sub.2SO.sub.3.sup., and R.sup.3 is H or C.sub.1-C.sub.4 optionally branched alkyl, and R.sup.2 and R.sup.3 are not simultaneously CH.sub.2OH and H, respectively. The reaction product of the saccharide polymer may be present in the aqueous phase at a concentration effective to lower a surface tension of the neutral surfactant.

Disclosed herein is method for conjugating a metal chelating agent to a functionalized dextran by reacting a chelator with an aminated dextran backbone, where the chelator comprises a one, and only one, derivatized carboxylic acid group to form a chelator-dextran complex. In certain aspects, the dextran-chelator complex is substantially free of intra- or intermolecular crosslinking. In certain aspects, the functionalized dextran is an amine dextran, an alkynyl dextran, or a thiol dextran. In exemplary implementations, the functionalized dextran is an amine dextran. In further embodiments, one and only one carboxylic acid group on the chelating agent is derivatized as a N-hydroxysuccinimide (NHS) ester.

Disclosed herein are compositions comprising at least one alpha-glucan graft copolymer derivative compound (e.g., ether or ester) having a degree of substitution (DoS) up to about 3.0. The precursors of these derivative compounds are graft copolymers that comprise a dextran backbone and alpha-glucan side chains. At least about 30% of the glycosidic linkages of the alpha-glucan side chains are alpha-1,3 glycosidic linkages. Further disclosed are methods of producing graft copolymer derivatives, as well as their use in various applications and products.

Compositions comprising a reaction product of a saccharide polymer and a fatty acid or a fatty ester may be obtained in an aqueous phase in the presence of a hydroxide base and a neutral surfactant, the saccharide polymer comprising a dextran, a dextrin compound, or any combination thereof. The neutral surfactant may comprise at least one compound having a structure of

##STR00001##

in which R.sup.1 is a saturated or unsaturated hydrocarbyl group having about 8 to about 30 carbon atoms; R.sup.2 is C.sub.1-C.sub.4 optionally branched alkyl, CH.sub.2OH, CH.sub.2O(CH.sub.2CH.sub.2O).sub.xCH.sub.2CH.sub.2OH (x is 0 or a positive integer), CH(OH)CH.sub.2OH, CO.sub.2H, or CH.sub.2SO.sub.3.sup., and R.sup.3 is H or C.sub.1-C.sub.4 optionally branched alkyl, and R.sup.2 and R.sup.3 are not simultaneously CH.sub.2OH and H, respectively. The reaction product of the saccharide polymer may be present in the aqueous phase at a concentration effective to lower a surface tension of the neutral surfactant.