a method of making a carboxylated carbohydrate is disclosed , cellulose being a preferred carbohydrate material . carboxylated cellulose fibers can be produced whose fiber strength and degree of polymerization is not significantly sacrificed . the method involves the use of a catalytic amount of a hindered cyclic oxammonium compounds as a primary oxidant and chlorine dioxide as a secondary oxidant in an aqueous environment . the oxammonium compounds may be formed in situ from their corresponding amine , hydroxylamine , or nitroxyl compounds . the oxidized cellulose may be stabilized against d . p . loss and color reversion by further treatment with an oxidant such as sodium chlorite or a chlorine dioxide / hydrogen peroxide mixture . alternatively it may be treated with a reducing agent such as sodium borohydride . in the case of cellulose the method results in a high percentage of carboxyl groups located at the fiber surface . the product is especially useful as a papermaking fiber where it contributes strength and has a higher attraction for cationic additives . the product is also useful as an additive to recycled fiber to increase strength . the method can be used to improve properties of either virgin or recycled fiber . it does not require high α - cellulose fiber but is suitable for regular market pulps .