Short communication, Note

https://doi.org/10.11613/BM.2019.010904

Plasma free DNA: Evaluation of temperature-associated storage effects observed for Roche Cell-Free DNA collection tubes

Dietmar Enko ; Institute of Clinical Chemistry and Laboratory Medicine, General Hospital Steyr, Steyr, Austria; Clinical Institute of Medical and Laboratory Diagnostics, Medical University Graz, Graz, Austria
Gabriele Halwachs-Baumann ; Institute of Clinical Chemistry and Laboratory Medicine, General Hospital Steyr, Steyr, Austria
Gernot Kriegshäuser ; Institute of Clinical Chemistry and Laboratory Medicine, General Hospital Steyr, Steyr, Austria; Clinical Institute of Medical and Laboratory Diagnostics, Medical University Graz, Graz, Austria

Abstract

Introduction: Standardized pre-analytical blood sample procedures for the analysis of circulating cell-free DNA (ccfDNA) are still not available.
Therefore, the present study aimed at evaluating the impact of storage conditions related to different times (24 and 48 h) and temperatures (room
temperature (RT) and 4 - 8 °C) on the plasma ccfDNA concentration of blood samples drawn into Cell-Free DNA collection tubes (Roche Diagnostics
GmbH, Mannheim, Germany).
Materials and methods: Venous blood from 30 healthy individuals was collected into five 8.5 mL Cell-Free DNA Collection Tubes (Roche Diagnostics
GmbH) each. Plasma samples were processed at time point of blood collection (tube 1), and after storage under the following conditions: 24 h
at RT (tube 2) or 4-8 °C (tube 3), and 48 h at RT (tube 4) or 4 - 8 °C (tube 5). Circulating cell-free DNA concentrations were determined by EvaGreen
chemistry-based droplet digital PCR (ddPCR).
Results: No statistically significant differences between median (interquartile range) plasma ccfDNA concentrations (ng/mL) at time point of blood
collection (3.17 (2.13 – 3.76)) and after storage for 24 h (RT: 3.02 (2.41 – 3.68); 4-8 °C: 3.21 (2.19 – 3.46)) and 48 h (RT: 3.13 (2.10 – 3.76); 4-8 °C: 3.09
(2.19 – 3.50)) were observed (P values from 0.102 – 0.975).
Conclusions: No unwanted release of genomic DNA from white blood cells could be detected in plasma samples after tube storage for 24 and 48 h
regardless of storage temperature.

Keywords

cell-free nucleic acids; pre-analytical phase; quality improvement

Hrčak ID:

217223

URI

https://hrcak.srce.hr/217223

Publication date:

15.2.2019.

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