Affordable 96-parallel SPPS: hardware and software add-on for automated liquid handling platforms

ParSynt-P is a hardware and software add-on that converts a liquid-handling robot already available in a proteomics laboratory (Tecan Freedom EVO) into a parallel plate-format peptide synthesizer for generating libraries of candidate peptide standards for targeted blood plasma proteomics. The manifold is milled from polytetrafluoroethylene and has ports for an inert gas and a vacuum line; a standard commercially available 96-well filtration plate is secured to it with an airtight seal. The software layer generates robot worklists from a table of peptide sequences and controls switching of the N?/vacuum lines, including pulsed gas mixing. The system performs up to 96 syntheses per run, and coupling of one residue takes 94 min. Workability of this 96-well format was verified on three fully loaded plates. The uniformity of synthesis conversion across the plate was measured quantitatively using a characterized NAT/SIL standard pair. The add-on cost $351, while the synthesis cost is $0.23 per coupling and $1.14 per milligram of crude product, an order of magnitude below the market price of custom synthesis.