The present invention provides a rotating microfluidic device capable of combining portions of various liquids into a single droplet, thus generating millions of droplets with differing compositions.

A fluid transfer system includes a transfer carousel capable of rotational and/or translational movement; at least one holding vessel (e.g. syringe) having a plunger, wherein the syringe is connected to the transfer carousel such that the movement of the transfer carousel results in movement of the syringe and wherein the syringe is capable of translational movement relative to the transfer carousel; a drive motor connected to the syringe that is capable of controlling the position of the plunger; and a peripheral module comprising at least one vessel that is capable of containing a fluid, wherein the vessel has an opening that can be mated with the syringe to allow fluid transfer between the vessel and the syringe. Methods for transferring a fluid are also disclosed.

A device capable of synthesizing a plurality of selected peptides by automatically mixing various amino acids, solvents, and activators and adding these to resins contained in a plurality of individual reaction vessels. A plurality of amino acids are contained in vessels within a carousel which is rotated into position where a syringe is inserted into a selected vessel to transport the amino acid within to a pre-reaction vessel for mixing with other selected amino acids which were previously drawn from the carousel. The mixture of amino acids is then transported to a reaction vessel containing the resin balls for growth of the selected peptide. The device includes a computer, controllable valves, at least one pump, pressurized gas such as nitrogen for transporting fluids, various vessels containing amino acids, solvents, activators, resins, and tubing connecting these elements. The computer is programmable to sample, mix selected components, and apply the mixture to resins for growing peptides.