Long-term stability of a stabilized liquid quality-control serum

Area of Science:

• Clinical Chemistry
• Laboratory Medicine
• Analytical Chemistry

Background:

• Quality-control materials are essential for accurate laboratory testing.
• Existing lyophilized controls require reconstitution, which can introduce variability.
• A novel liquid quality-control serum stabilized with ethylene glycol was developed.

Purpose of the Study:

• To assess the long-term stability of a new liquid quality-control serum.
• To evaluate its performance for 22 common analytes under different storage conditions.
• To compare its stability to existing lyophilized control materials.

Main Methods:

• Liquid control serum analyzed for 22 analytes over 24 days (2-8°C) and 55 weeks (-15 to -20°C).
• Multi-laboratory study with various analytical methods.
• Linear regression analysis used to determine analyte stability over time.

Main Results:

• All 22 analytes remained stable for at least 24 days at refrigerator temperature.
• All analytes were stable for at least 55 weeks at freezer temperature.
• The control serum demonstrated excellent long-term stability across multiple labs and methods.

Conclusions:

• The new liquid quality-control serum is a stable and satisfactory alternative to lyophilized materials.
• It offers advantages such as improved stability, vial-to-vial uniformity, reduced waste, and no need for reconstitution.
• This material enhances laboratory quality control efficiency and reliability.