This application note demonstrates an approach for rapidly optimizing a liquid class to dispense PlasProxyTM – a new MVS® QualAssure® solution that mimics the pipetting characteristics of various types of plasma – using an automated liquid handler (ALH). Utilizing the Multichannel Verification System (MVS) is crucial for conducting liquid class optimization quickly and efficiently. A liquid class with predetermined aqueous settings was used to dispense PlasProxy and Aqueous QualAssure solutions, and two species of commercially available plasma. The liquid class was then modified to properly dispense PlasProxy and the subsequent volume was measured using the MVS, recording the new settings each time. Once finalized, the optimized method was used to dispense PlasProxy and the other three test solutions. Volume measurements were recorded using the MVS and gravimetry when conducting dispenses prior to and following the liquid class optimization. This paper illustrates an ideal liquid class optimization process using PlasProxy, a suitable mimic for commercially available plasma, on an ALH.
Automated liquid handlers are important for the automation of a wide range of assay workflows, intended to minimize hands-on time and reproducibility errors that might be experienced with manual pipetting. Critical assay results are influenced by the accuracy of volume delivery. The set of programming commands used to control an ALH must be manipulated to properly dispense a given test solution based mainly on its fluidic properties, including but not limited to viscosity, density, and surface tension. These properties can have significant effects on the pipetting performance of the solution under test. The set of ALH programming steps required for a particular group of liquids is known as a liquid class. For example, viscous solutions and aqueous solutions generally require different liquid handling protocols meant to best dispense that kind of liquid.