The present invention is directed to novel aminooxy-cyclodextrin derivatives of the formula (1): CD—(X—Y—ONH₂)_n, wherein CD is mono- or polydeoxy -, -, or -cyclodextrin, carrying in its 6-, 3- and/or 2-position a group containing the aminooxy group, and optionally carrying substituents different from (X—Y—ONH₂). Y is a linker group between the aminooxy group and the mono- or polydeoxy-CD group, X is a functional group or an atom necessary to connect the linker Y and the deoxy CD group, or Y is a direct bond when X is a direct bond, and n is 1, but 24, 21 and 18 for -, - or -cyclodextrin, respectively, the protected aminooxy derivatives thereof, as well the methods for their preparation and use.