Design and operation of a completely automated Beckman microsequencer

A unique, efficient, and inexpensive system has been designed and built for the automatic conversion of anilinothiazolinone derivatives extracted from a Beckman spinning-cup sequencer with subsequent on-line high-pressure liquid chromatography separation of the phenylthiohydantoin derivatives. The Auto Converter-Auto Sampler system is controlled by a tape programmer or microprocessor and operates by transfer of the sample from the conversion vial into an HPLC injection loop by nitrogen pressure. Incorporation of a minor programming change on the sequencer allows the introduction of nitrogen vapor into the spinning cup during phenylisothiocyanate coupling. These modifications have resulted in a completely automated subnanomole protein sequencer.