Background and Technology
Nucleic acid medicines and mRNA vaccines have been clinically applied, and synthetic genome research and DNA memory development have become active. While the sequencing cost has dropped dramatically with the advent of the next-generation sequencer, the synthesis cost is as high as several cents / bp, and further cost reduction is required.
Widely used phosphoramidite method, is composed of steps; (1) deprotection step of 5’hydroxyl group of solid-phase substrate-linked nucleoside, (2) coupling step to the 5’hydroxyl group of the nucleoside phosphoramidite unit in the presence of an activator, (3) unreacted 5’hydroxyl capping process, (4) phosphite oxidation process, (5) deprotection and cutting out of substrate after repeat of (1) to (4).
Although fairly high reaction efficiency has been established, improving reaction efficiency and productivity is important for cost reduction in especially long-stranded nucleic acid synthesis.
Technology 1) Modified phosphoramidite method
– Immobilized activator on monomer substrate, optimized activator, linker, reaction conditions.
– Maintains reaction efficiency of > 99.8% at > 100 mer (synthetic purity twice that of conventional method at 40 mer).
– Applicable to RNA synthesis, artificial nucleic acids, sulfurization.
Technology 2) High Density Optical Multiple Sequence Flow Synthesis System
– Introduced porous plate instead of the current plain type, reaction field made three-dimensional by optimizing pore size and solvent.
– Area efficiency 5000 times, plate area reduced to 1/170 in synthesis of multiple types of sequences using DMD (Digital Mirror Device). High productivity expected due to miniaturization of the equipment.
Patent & Publication
Technology 1) JP2019-031683
Technology 2) not published
Partly presented at 6th Annual Meeting of NatsJ, ISNAC2021
Associate Professor, Akihiro Ohkubo, Tokyo Institute of Technology, Japan
Technology 1) Licensable to CDMO of nucleic acids, reagent suppliers.
Technology 2) Seeking partner to develop flow system. Now prototype has been developed.
Product No. KJ-04131