Patent ID: 7381572

Claim:
A detectable complex comprising: (a) at least one target material; (b) a first peptide tag bound to said at least one target material; (c) a second peptide tag bound to said at least one target material, wherein the second peptide tag is different from said first peptide tag; (d) a first conjugate having a detectable group and two pendant phenylarsine moieties comprising a first tag binding group; wherein said first conjugate preferentially associates with said first peptide tag; (e) a second conjugate having a detectable group and two pendant phenylarsine moieties comprising a second tag binding group; wherein said second conjugate preferentially associates with said second peptide tag; wherein the mean distance and/or mean angle between said pendant phenylarsine moieties in said first conjugate is different from the mean distance and/or mean angle between said pendant phenylarsine moieties in said second conjugate; and wherein at least one of said first and second conjugates is represented by the general structural Formula (I): wherein: (i) R 1 and R 2 , together with the arsenic atom, form a ring according to the general structural Formula (IIB),: wherein Z represents a hydrocarbon chain comprising 2-4 singly or doubly bonded carbon atoms wherein each carbon atom may be further substituted with one or more groups selected from hydrogen, methyl, ethyl, 1-propyl, 2-propyl, methoxy, hydroxy, amino, carboxy, sulfo, oxo, thiol, halo (fluoro, chloro, bromo, or fluoro), (CH 2 ) n″ SO 3 - and (CH 2 ) n″ SO 3 H, wherein n″ is 1 or (ii) R 4 , R 5 , R 6 and R 7 are each independently H, F, OR 3 , R 3 , OAc, NH 2 , N(C 1 -C 4 alkyl) 2 ; or R 4 with R 5 , or R 6 together with R 7 , or both, form a ring; (iii) R 8 is a linear or branched optionally substituted spacer having a minimum length of approximately 1.5 Ångstroms and a maximum length of approximately 15 Ångstroms; and (iv) X is cyanine.