Automated nucleic acid isolation in viral molecular diagnostics: evaluation of the QIAsymphony SP

Abstract

The Qiagen QIAsymphony SP is a high-throughput (up to 96 samples per run), fully-automated nucleic acid isolation system. It was implemented in the authors' laboratory to cope with the high demand for pandemic H1N1 influenza testing in 2009. This study evaluated the QIAsymphony SP for viral nucleic acid isolation from quality control materials, pure cultures and various clinical specimens. The effect of varying sample volume on detection sensitivity was investigated using serial 10-fold dilutions of pure viral specimens and target nucleic acids were detected by real-time polymerase chain reaction (PCR) assays. Little variability in detection sensitivity was observed for all the viral targets tested, although variation in cycle threshold values was apparent in some cases. Importantly, pathogens were detectable over a broad concentration range and from diverse clinical specimens. Removal of PCR inhibitors was generally effective, as demonstrated by detection of viral nucleic acids and/or internal controls. The results demonstrate that the QIAsymphony SP is suitable for use in routine virology molecular diagnostics, and provides a high-throughput capacity, which is needed in peak seasons of infection or in centralised laboratories.