Volumetric Performance Assessment of Automated Liquid Handling Systems with ISO IWA 15
By Carle, A.B., Rodrigues, G. | Poster
The use of Automated Liquid Handling Systems (ALHS) is nearly ubiquitous in modern life sciences, clinical, forensic, as well as other analytical laboratories. These automated systems range from simple dispensers to highly sophisticated systems, which sometimes include functions that reach well beyond mere liquid handling tasks. The core functionality of ALHS, however, is to accurately and precisely dispense or transfer small volumes of liquids, often into microplates of 96- or 384-well format. Most ALHS offer adjustments to instrument settings, so that the ALHS performance can be optimized for a given liquid type, volume range, labware types, or environmental conditions. In the past, it has been left to the individual laboratories and ALHS manufacturers to devise suitable test regimens to assess and describe the volumetric performance of such systems. As expected, inconsistent use of test methods, statistics, and reports, led to inconsistency in the assessment of an ALHS’ performance. In 2015, the International Organization for Standardization (ISO) published a new document, ISO IWA 15, which fills the void in ISO documents describing standardized ways of determining the performance of ALHS. While ISO standards exist for the calibration of piston-operated pipettes and other volumetric apparatus (ISO 8655, parts 1 to 7) and volumetric glass pipettes (ISO 4787), there was no global document addressing the performance assessment of automated liquid handling systems. This void has been closed with the development and publication of ISO IWA 15. ISO IWA 15 provides laboratories and manufacturers with an extensive list of 50 definitions of ALHS-related terms, including detailed definitions of trueness, precision, and accuracy in volumetric measurements. Further, the document guides the laboratory on using descriptive statistics models to properly describe measured ALHS volumetric performance on the basis of channels, dispense order, and run order. Detailed descriptions of 13 test methods suitable to measure the volumetric performance of ALHS are presented, in addition to requirements for test and calibration reports. This poster will describe key elements of ISO IWA 15 and how ALHS users and manufacturers will benefit from following the guidelines and tests in this document. Optimized ALHS performance, as determined by standardized methods and statistical models, will allow to objectively cross-compare ALHS performance across all laboratory sites and ALHS makes and models, for truly standardized laboratory operations.