Chemiluminescence imaging probes for in vivo detection of biological molecules, events, or processes. The CLI probes may feature a portion of a fluorescein molecule and a portion of a luminol molecule. The fluorescein molecule and luminol molecule may be linked by a non-xanthenic aromatic ring. The CLI probes are generally non-toxic and soluble in aqueous solutions such as PBS. The CLI probes may be used to detect specific molecules in vivo.