Pre-analytical operating procedures for serum Low Molecular Weight protein profiling.

Area of Science:

• Proteomics
• Biochemistry
• Analytical Chemistry

Background:

• Serum specimen collection and storage are critical for proteomics research.
• Standardized protocols for Low Molecular Weight (LMW) proteome profiling are lacking.
• Pre-analytical variables can significantly impact proteomic data.

Purpose of the Study:

• To systematically analyze the influence of pre-analytical factors on serum LMW proteome profiling.
• To compare manual versus automated peptide purification methods.
• To establish optimal conditions for serum sample collection and storage for LMW proteome analysis.

Main Methods:

• Analysis of serum LMW proteome profiling under varying clotting times, storage temperatures, and storage durations.
• Investigation of protease inhibitor (PI) effects on serum LMW proteome.
• Comparison of manual and automated peptide purification using magnetic bead-based MALDI-MS.

Main Results:

• Optimal serum LMW protein recovery and stability were achieved with 1-2h clotting time and storage up to 2h at room temperature or 4°C.
• Protease inhibitor addition to whole blood reduced the number of detected LMW peaks.
• Serum proteome profiles showed minimal changes after 1-month storage at -80°C, irrespective of PI addition.

Conclusions:

• Standardized pre-analytical and storage procedures are essential for minimizing bias in serum LMW profiling.
• Automated peptide purification enhances homogeneity and reproducibility in proteomics studies.
• Implementing these optimized protocols will improve the reliability of future serum proteomics research.