Vortex autosampler consists of an integrated autosampling device and multi-stirrer, and increases efficiency, enhances precision, and promotes operator safety. The temperature-controlled, heated (up to 150 C) multi-stirrer assembly features a stainless steel tray that handles 20- and 40-ml vials. Each vial position has its own magnetic stirring mechanism for consistent and reproducible stirring action from vial to vial and to eliminate variability due to the dissolution process. Coupled with the Triple Detector Array (TDA) or Relative Viscometer, the Vortex provides a complete automated system for macromolecular characterization and determination of solution viscosities.