Saponin derivative based on a saponin comprising a triterpene aglycone core structure and at least one of a first saccharide chain 'R 1 ' and a second saccharide chain 'R 2 ' linked to the aglycone core structure, wherein the saponin derivative comprises an aglycone core structure comprising an aldehyde group, wherein the saponin on which the saponin derivative is based is a mono-desmosidic or bi-desmosidic triterpene saponin belonging to the type of a 12,13-dehydrooleanane with the aldehyde group in position C-23, and wherein the aldehyde group is transformed into a semicarbazone functional group according to formula wherein R 1 and R 2 are independently selected from a monosaccharide, a linear oligosaccharide and a branched oligosaccharide, X = O, P or S, preferably wherein X = O, and Y = NR 3 R 4, wherein R 3 and R 4 independently represent H, an unsubstituted C1 - C10 straight chain, branched or cyclic alkyl, an unsubstituted C2 - C10 straight chain, branched or cyclic alkenyl or an unsubstituted C2 - C10 straight chain or branched alkynyl, or a covalently bound linker, preferably one of R 3 and R 4 is H; or Y = wherein n and m each are an integer independently selected from 1, 2, or 3, Z = CH 2, O, S, P or NR 5, and wherein R 5 represents H, an unsubstituted C1 - C10 straight chain, branched or cyclic alkyl, an unsubstituted C2 - C10 straight chain, branched or cyclic alkenyl, an unsubstituted C2 - C10 straight chain or branched alkynyl, or a covalently bound linker, or a maleimide moiety according to formula a or formula b or an azide moiety according to formula c wherein o is an integer selected from 0-10, preferably 2-7, more preferably 4-6, and W is a thiol functional group according to formula wherein U = SH, NH 2 or OH and p is an integer selected from 0-4, preferably 1-3, more preferably 1 or 2. wherein R 1 and R 2 are independently selected from a monosaccharide, a linear oligosaccharide and a branched oligosaccharide, X = O, P or S, preferably wherein X = O, and Y = NR 3 R 4, wherein R 3 and R 4 independently represent H, an unsubstituted C1 - C10 straight chain, branched or cyclic alkyl, an unsubstituted C2 - C10 straight chain, branched or cyclic alkenyl or an unsubstituted C2 - C10 straight chain or branched alkynyl, or a covalently bound linker, preferably one of R 3 and R 4 is H; or Y = wherein n and m each are an integer independently selected from 1, 2, or 3, Z = CH 2, O, S, P or NR 5, and wherein R 5 represents H, an unsubstituted C1 - C10 straight chain, branched or cyclic alkyl, an unsubstituted C2 - C10 straight chain, branched or cyclic alkenyl, an unsubstituted C2 - C10 straight chain or branched alkynyl, or a covalently bound linker, or a maleimide moiety according to formula a or formula b wherein n and m each are an integer independently selected from 1, 2, or 3, Z = CH 2, O, S, P or NR 5, and wherein R 5 represents H, an unsubstituted C1 - C10 straight chain, branched or cyclic alkyl, an unsubstituted C2 - C10 straight chain, branched or cyclic alkenyl, an unsubstituted C2 - C10 straight chain or branched alkynyl, or a covalently bound linker, or a maleimide moiety according to formula a or formula b or an azide moiety according to formula c wherein o is an integer selected from 0-10, preferably 2-7, more preferably 4-6, and W is a thiol functional group according to formula wherein U = SH, NH 2 or OH and p is an integer selected from 0-4, preferably 1-3, more preferably 1 or 2. wherein o is an integer selected from 0-10, preferably 2-7, more preferably 4-6, and W is a thiol functional group according to formula wherein U = SH, NH 2 or OH and p is an integer selected from 0-4, preferably 1-3, more preferably 1 or 2. wherein U = SH, NH 2 or OH and p is an integer selected from 0-4, preferably 1-3, more preferably 1 or 2.