(1015-B) Increased throughput, walk-away time and efficiency with Tecan automated cIEF sample preparation

Abstract: Capillary isoelectric focusing (cIEF) is recognised as a gold standard method for monitoring charge heterogeneity in biopharmaceutical product development. However, the manual sample preparation for cIEF is labour-intensive, making it time-consuming and error-prone (repeat rates of 10% are expected). We have developed and assessed an automated sample preparation method for monoclonal antibody (mAb) cIEF analysis using a robotic liquid handler (Tecan Freedom EVO® 200). Our method is capable of performing stepwise dilutions with either water or viscous urea-based solutions, and achieves a high dilution factor of up to 665. Furthermore, it offers individual sample dilution control for a wide range of starting concentrations (5-100 mg/mL). Measurements of repeatability, intermediate precision, and accuracy over the initial concentration range showed acceptable coefficients of variation (≤2.9%, ≤6.2% and ≤6.6% respectively). cIEF data acquired for a reference sample using the automated method was shown to fall within the manual variability limits (2 standard deviations of percentage peak area). The automated method was successfully implemented to support cIEF analysis of a mAb development activity, without the need for repeat analyses. Using our method, three hours of hands-on analyst time is saved for every 20 samples prepared; increasing the throughput, walk-away time and efficiency of cIEF analysis.