This research article presents a simple and cost-effective chromatographic approach for the purification of urinary free light chains (FLCs), including both lambda and kappa free light chains, from urine samples. The study combines chromatographic purification with peptide mass fingerprinting to enable large-scale isolation and characterization of these clinically important biomarkers.

The purified FLCs were validated using SDS-PAGE, immunoblotting, and MALDI-TOF mass spectrometry, confirming their purity, molecular identity, and structural relevance. This work represents the first report of characterization and validation of urinary free light chains following large-scale purification, supporting their potential use in bioclinical research and diagnostic applications.