Fig. 3: The automated fast-flow instrument features six modules that act to effect rapid PMO synthesis.
From: Fully automated fast-flow synthesis of antisense phosphorodiamidate morpholino oligomers
a A schematic for the flow path of the instrument is shown. Valves select the appropriate solutions from glass bottles under nitrogen pressure. Two HPLC pumps mix the reagents and flow them over a packed resin bed held at 90 °C. Effluent cools as it exits the reactor and passes through a back-pressure regulator to an in-line UV–vis detector, where reaction progress is monitored. A computer running an automated Python script controls the valves and pumps throughout the synthesis, and tracks the instrument performance from the UV–vis detector. b The optimized protocol for PMO synthesis is shown. Instructions are delivered by the control program to the pumps and valves at each of the listed times. Bars represent activity of the two HPLC pumps, and colors indicate which reagents the valves are open to. Reagent stocks are prepared in double the concentration that is intended to hit the resin. Dilution from the second pump prepares the correct concentrations upon mixing.
