Related Experiment Videos
Optimal collection and storage conditions for catecholamine measurements in human plasma and urine
F Boomsma1, G Alberts, L van Eijk
1Cardiovascular Research Institute COEUR, University Hospital Dijkzigt/Erasmus University, Rotterdam, The Netherlands.
Insights
Optimal storage of catecholamines (CA) involves prompt blood centrifugation and specific temperature/preservative conditions for plasma and urine. These findings ensure accurate CA measurements for clinical trials and patient screening.
Area of Science:
- Clinical Chemistry
- Biochemical Analysis
- Analytical Toxicology
Background:
- Catecholamines (CA) are increasingly utilized as biomarkers in patient screening and clinical trials.
- Accurate measurement of CA relies on proper sample preparation and storage.
- Logistical challenges in sample handling necessitate optimized protocols.
Purpose of the Study:
- To determine optimal conditions for the preparation and storage of plasma and urine samples for catecholamine analysis.
- To address the unresolved questions regarding sample stability and integrity.
Main Methods:
- Investigated the stability of catecholamines in plasma and urine under various storage conditions (temperature, time, preservatives).
- Blood samples were centrifuged at different time points post-collection.
- Plasma and urine samples were stored at temperatures including 20°C, 4°C, -20°C, and -70°C.
- Urine samples were tested with and without preservatives like EDTA and sodium metabisulfite, and also in acidified conditions.
Main Results:
- Blood centrifugation within 1 hour of collection is recommended; refrigeration is not essential.
- Plasma catecholamines are stable for 1 day at 20°C, 2 days at 4°C, 1 month at -20°C (6 months with glutathione), and 1 year at -70°C.
- Unpreserved urine catecholamines are stable for 1 month at 4°C.
- Preserved urine (EDTA, sodium metabisulfite) shows stability for 4 months at 4°C.
- Acidified urine samples maintained catecholamine integrity for over 1 year at both 4°C and -20°C.
Conclusions:
- Established optimal sample preparation and storage guidelines for catecholamines in plasma and urine.
- The findings provide practical recommendations to ensure the reliability of catecholamine measurements in clinical settings.
- Proper sample handling protocols are crucial for accurate biomarker utilization in research and diagnostics.
Abstract:
Improvements in methodologies for measuring concentrations of catecholamines (CA) have led to an increasing use of these compounds as markers in the screening of patients and in long-term clinical trials. Because of the associated logistical problems, we have investigated the unresolved question of optimal conditions for sample preparation and for storage of plasma and urine samples. Results show that blood should be centrifuged within 1 h after collection; the use of a refrigerated centrifuge is not necessary. Once plasma is prepared, CA are stable for 1 day at 20 degrees C, 2 days at 4 degrees C, 1 month at -20 degrees C (or 6 months with added glutathione), and up to 1 year at -70 degrees C. CA are stable at 4 degrees C for 1 month in unpreserved urine and for 4 months in urine preserved with EDTA and sodium metabisulfite. In acidified urine, CA were nearly unchanged after 1 year at 4 and -20 degrees C.