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Split-and-pool Synthesis and Characterization of Peptide Tertiary Amide Library
Published on: June 20, 2014
Stability of serum alanine aminotransferase activity
Transfusion
|September 1, 1987
Summary
Proper serum storage is crucial for accurate alanine aminotransferase (ALT) testing. Storing separated serum at 4°C for up to a week and frozen samples at -80°C minimizes ALT activity loss, ensuring reliable diagnostic results.
Area of Science:
- Clinical Biochemistry
- Laboratory Medicine
- Biochemical Analysis
Background:
- Serum alanine aminotransferase (ALT) is a key biomarker for liver health.
- Standardized storage and handling protocols are essential for accurate ALT level determination.
- Variations in temperature and sample preparation can impact ALT stability.
Purpose of the Study:
- To investigate the impact of common storage and handling conditions on serum ALT levels.
- To determine optimal storage temperatures and durations for preserving ALT activity.
- To assess the influence of sample separation and red blood cell lysis on ALT quantitation.
Main Methods:
- Clotted blood samples from 14 subjects were analyzed.
- Serum was separated and stored at various temperatures (22°C, 4°C, -20°C, -80°C).
- ALT activity was measured at multiple time points up to 8 days, including comparisons of separated vs. unseparated samples.
Main Results:
- Gradual ALT activity loss occurred across all storage conditions over time.
- Separated serum stored at 4°C showed a 6% loss at 2 days, while at 22°C, it was 20%.
- Storage at -20°C led to significant ALT loss (46% by day 6), whereas -80°C resulted in only an 8% decrease.
Conclusions:
- For short-term storage (up to 1 week), early serum separation and refrigeration at 4°C are recommended.
- Long-term storage should utilize -80°C to maintain ALT stability.
- Standard blood collection center conditions (24 hours at 4°C or 22°C) have a minor adverse effect on ALT accuracy.
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