Provided herein are methods and compositions for oligonucleotide synthesis utilizing universal linker phosphoramidites. Methods and reagents are described with DNA synthesis using controlled pore glass (CPG) solid supports, and on platinum coated electrodes for electrochemical DNA synthesis. The universal linkers can be used as spacers in single-column PCR primer synthesis to generate 2 strands with free 3′-hydroxy termini after cleavage. The methods and compositions utilize a solid support system for synthesis of oligonucleotides, wherein the support has platinum electrodes and a universal linker, optionally wherein the platinum electrode is coated with an amine. The methods and compositions further describe use of universal linker phosphoramidites and the platinum electrode is coated with a monosaccharide, or a disaccharide.