Comparison of RNA Extraction Method for Human Whole Blood: Assessing the Quality, Quantity, and Impact of RBC Lysis Across TRIzol, Invitrogen, and Qiagen Systems

Whole-blood samples are widely utilized in the field of doping control. Owing to the limited volume of whole blood collected from athletes and the fact that Tempus Blood RNA Tube and Paxgene Blood RNA Tube are primarily intended for RNA stabilization and require dedicated extraction workflows, this study aimed to develop a more efficient and cost-effective RNA extraction approach using smaller volumes of EDTA-anticoagulated whole blood. RNA was extracted from human whole blood using three different methods: the TRIzol Reagent, the PureLink RNA Mini Kit (Invitrogen), and the QIAamp RNA Blood Mini Kit (Qiagen). Apparent RNA yield and purity were assessed via a NanoDrop spectrophotometer, and RNA suitability for RT-qPCR analysis was evaluated. The results indicate that red blood cell lysis influenced RNA extraction outcomes. Additionally, clear differences in RNA quality and quantity were observed. Among the three methods evaluated, the QIAamp RNA Blood Mini Kit (Qiagen) tended to yield higher apparent RNA concentrations, purity, and integrity. Therefore, under the exploratory conditions tested, the QIAamp RNA Blood Mini Kit (Qiagen) demonstrated comparatively favorable performance for RNA-based biomarker analysis relevant to doping control.