Synthesis of high density molecular dna brushes via organic-phase ring-opening metathesis (co)polymerization

A method of synthesizing a protected norbornenyl DNA monomer or protected norbornenyl RNA monomer (protDNA) comprising the steps of:

• 1) providing a controlled pore glass (CPG) solid support for oligonucleotide synthesis, wherein the CPG solid support has covalently bound thereon a disulfide linker;
• 2) conducting a solid-phase oligonucleotide synthesis reaction with ultramild cyanoethyl (CE) phosphoramidites on the CPG solid support to form a protected oligonucleotide having a predetermined nucleotide sequence covalently bound at the 3′ end thereof to the disulfide linker;
• 2) cleaving the disulfide linker under conditions that release the protected oligonucleotide from the solid support, thereby forming a sulfhydryl group at the 3′end of the protected oligonucleotide;
• and
• 3) coupling an iodoacetyl- or a maleimide-functionalized norbornene monomer to the sulfhydryl group of the protected oligonucleotide via a SN2 or Michael addition reaction, respectively, to produce a protected norbornenyl DNA monomer or protected norbornenyl RNA monomer.