The present disclosure generally pertains to systems and methods for the chemical synthesis of micro-quantities of oligonucleotides or other chemical molecules. The system includes a reusable glass micro-reactor containing a paramagnetic solid support, a magnet, an electronic drive controller and an optical spectroscopy system capable of driving a plurality individual reactors. The system utilizes the electroosmotic movement of reactants through microfluidic channels. Spectrophotometric monitoring of the reaction products allows for the real-time determination of synthesis yield.