bonding compound that can react with the first protein area reacted in a buffer and a protein conjugate is prepared next 2 a second protein and a cyanine labeling dye expressed in chemical formula 1 are reacted in the buffer and a dye labeled protein is prepared then 3 a protein conjugate and the dye labeled protein are mixed in the buffer and the protein conjugate and the dye labeled protein are reacted thus a dye labeled protein conjugate is prepared this embodiment is further described below in the pbs of bsa as first protein a pbs of cyanine labeling dye expressed in chemical formula 1 is added and stirred for about 12 hours at about 40 to 30 u00b0 c it is then reduced in dtt a preliminarily pyridyl thio labeled second protein for example mouse igg is added therein and stirred for about 12 hours at about 40 to 30 u00b0 c thus a dye labeled protein conjugate is prepared in the compound expressed in chemical formula 1 halogen x is for example fluorine chlorine bromine or iodine and m is hydrogen lithium sodium or potassium the invention is further described below by referring to specific embodiments in the compound expressed in chemical formula 1 of the embodiment x is iodine m is potassium and number of carbon atoms n is 2 the protein is igg and bsa the cyanine labeling dye expressed in chemical formula 1 is abbreviated as slic3 in 2 ml.