Patent ID: 7338805

Claim:
A temperature-stable labeling reagent of formula (0): in which: R 1 represents H or an alkyl, aryl or substituted aryl group, R 2 represents a detectable marker or at least two detectable markers linked together by at least one multimeric structure, L is a linking arm containing a linear succession of at least two covalent bonds and n an integer equal to 0 or 1, R 3 and R 4 represent independently of each other: H, NO 2 , Cl, Br, F, I, R 2 -(L) n -Y—X—, OR, SR, NR 2 , R, NHCOR, CONHR, COOR with R=alkyl or aryl, A is a linking arm containing at least one covalent double bond allowing conjugation of the diazo functional group with the aromatic ring and u is an integer from 0 to 2, and —Y—X— represents —CONH—, —NHCO—, —CH 2 O—, or —CH 2 S—, with the proviso that when n is equal to 1, L comprises a unit including at least one —(O—CH 2 —CH 2 )—, or —Y—X— represents —NHCO—, CH 2 — or —CH 2 S—, wherein the labeling reagent is stable for roughly 2 days at −20° C., wherein the labeling reagent is an ortho or meta species of formula (0), and wherein the detectable marker is at least one marker capable of directly or indirectly generating a detectable signal, and the detectable marker is selected from the group consisting of an enzyme, a chromophore, a group with an electron density detectable by electron microscopy, a group with an electron density detectable by its electrical property, or a radioactive molecule.