Ring-opening metathesis polymers for biodetection and signal amplification: Synthesis and self-assembly

The ring-opening metathesis polymerization (ROMP) was used to develop a new class of block copolymers toward biological detection with signal amplification. For this, three classes of ROMP monomers were synthesized: (i) luminescent and electrochemiluminescent transition-metal-containing monomers, with ruthenium, osmium, and iridium bipyridine units, (ii) biologically compatible monomers and macromonomers containing oligothylene glycol units, and (iii) bioconjugatable monomers as well as monomers containing the biorecognition unit biotin. ROMP was used to efficiently combine these monomers into amphiphilic di-and triblock copolymers. Self-assembly of these block copolymers in aqueous media generates micellar spherical assemblies, which containa large number of luminescent transition-metal centers in their core, a biocompatible and biologically inert protecting shell, and biological recognition units or bioconjugatable groups on their periphery. These micelles can act as luminescent markers for biological molecules with potential for signal amplification. In addition, the monomers and polymers reported here can serve as useful biologically enabled building blocks for a number of applications, including drug delivery and tissue engineering.