Coupling reagents, nucleotide peptide

DNA synthesizers operate on a principle similar to that of the Merrifield solid-phase peptide synthesizer (Section 26.8). In essence, a protected nucleotide is covalently bonded to a solid support, and one nucleotide at a time is added to the growing chain by the use of a coupling reagent. After the final nucleotide has been added, all the protecting groups are removed and the synthetic DNA is cleaved from the solid support. Five steps are needed ... 

More recently, automated gene synthesizers have been developed that operate on principles similar to the Merrifield solid-phase technique for peptides. A protected nucleotide is covalently bonded to a polymer. Other protected nucleotides are then added sequentially to the chain, using a coupling reagent. Eventually, the protecting groups are removed, and the synthetic oligonucleotide is then detached from the solid support. 

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