Dual mobile phase apparatus and method

A process for solid phase synthesis, comprising moving an elongate solid phase through an apparatus for contacting the elongate solid phase with a flowing liquid phase, the elongate solid phase comprising a substrate and optionally a substance bonded thereto and the apparatus comprising:

• a conduit which is of circular or non-circular transverse cross section and which defines a lumen to contain both the flowing fluid phase and the mobile elongate solid phase;
• liquid phase ports in communication with the lumen to allow the fluid phase to enter the lumen, flow through it and exit it;
• solid phase ports in communication with the lumen to allow the mobile solid phase to enter the lumen, move through it and exit it;
• a controllable drive device for moving the solid phase through the conduit, the drive device comprising a drive motor coupled to a drive roller;
• and
• a fluid metering device for providing a fluid phase flow to the conduit,
• wherein the solid phase ports are spaced above the fluid phase ports, whereby in use the liquid phase does not contact the solid phase ports, and wherein a guide roller is arranged to guide the solid phase before it enters or, as the case may be, after it exits a said solid phase port, the apparatus being a first said apparatus and being in combination with a second said apparatus to provide a pathway along which the elongate solid phase moves out of a solid phase port of the first apparatus and into a solid phase port of the second apparatus via the roller, and wherein the solid phase pathway includes a plurality of guide rollers for guiding the solid phase along the pathway, wherein a said guide roller is the drive roller,
• the process comprising moving the solid phase through:
• at least two synthesis zones in which the solid phase is contacted with a synthetic building block that, when so contacted, reacts with a reactive group to become bound to the substrate or with a moiety already formed by one or more previous synthetic building blocks, the synthetic building blocks being contacted with the solid phase by contacting the solid phase with a flowing liquid phase using a said apparatus, the liquid phase flowing through the lumen of each apparatus in an opposite direction to the movement of the solid phase;
• a washing zone in which the solid phase is washed after being contacted with a reagent, in order to remove unreacted reagent, the solid phase being contacted with a flowing liquid phase using a said apparatus;
• a deprotection zone in which the solid phase is contacted with a flowing liquid phase using an apparatus of the invention to deprotect a protected functional group of a moiety bound to the substrate prior to a synthesis step;
• and
• a cleaving zone for cleaving attached molecules from the solid phase using an apparatus of the invention.