New labeling probes of fluorescenced and ^<68>Ga-DOTA, as the positron emission nucleus for PET, througn rapid 6π-azaelectrocyclization were designed and synthesized, (E)-ester aldehydes 1. The high reactivity of these probes enabled the labeling of lysine residues in peptides, proteins, and even the amino groups on the cell surfaced at very low concentration (-10^<-8>M) within a short recation time (-10min) to result in "selective" and "non-destructive" labeling of the more accessible amines. The first microPET of glycoproteins, ^<68>Ga-DOTA-orosomucoid and asialoorosomucoid successfully visualized the differences in the circulatory residence of glycoproteins, in the presence or absence of the sialic acids. New N-glycan clusters with MW of 50KDa were also developed and their in vivo dynamics, being affected significantly by their glycan structures, could be visualized through the present amine-labeling & PET and/or noninvasive fluorescence imaging. The azaelectrocyclization-based biocojugation is also applicable to the engineering of the proteins and/or the cell surfaces by the oligosacchrides; the chemically engineered lymphocytes by N-glycan sussessfully traget the tumor tissue implanted in the BALB/c nude mice, based on the noninvasive fluorescence imaging.