Improved resolution of serum bisalbumin on electrophoresis and investigation of bisalbumin in urine

Objectives: The aims of this study were to improve the resolution of albumin variants (bisalbumins, especially albumin Naskapi) from albumin in commercial serum protein electrophoresis systems; to compare the separation of bisalbumin from albumin on these improved methods against the recognized gold standard of capillary electrophoresis; and to investigate the presence of albumin variants in urine. Design and methods: Electrophoresis was performed using the Sebia Hydrasys 15/30 β1β2 system, as well as modified methods on the Sebia Hydrasys HR and the Beckman Paragon systems. The interpretation of electrophoretic gels was performed by manual visualization and densitometric scanning. Serum samples were also analyzed using capillary electrophoresis at Sebia Électrophoresé located in Paris, France. Urine samples were concentrated using Vivaproducts concentration tubes and were electrophoresed using the Sebia Hydrasys HR system. Results: Representative gels and scans of serum samples demonstrate the improved resolution of modified electrophoresis methods compared to routine methods. The raw data from the gels and scans were compiled to calculate concordance and discordance for each method. Discussion: The various commercial serum protein electrophoresis systems showed improved resolution using the modified methods. In comparison with capillary electrophoresis, the modified Sebia Hydrasys HR and Beckman Paragon methods using visualization demonstrated 100% concordance and thus performed equally as well as the gold standard. Urine studies found that variant albumins are also excreted in the urine in the same 50–50 ratio as that found in the serum.