Serum/Plasma Protein Electrophoresis with Bromocresol Green (BCG) Dye Binding Assay

What This Test Measures

The test uses bromocresol green dye to bind to specific proteins in your serum or plasma. As the dye binds, it changes color, allowing lab technicians to separate and quantify different protein fractions—such as albumin and globulins—based on their size and charge. This helps detect abnormalities in protein composition, which may indicate conditions like multiple myeloma, liver disease, or other protein-related disorders.

Why It’s Done

Your healthcare provider may order this test to investigate symptoms like unexplained weight loss, fatigue, swelling, or changes in blood tests. It’s also used to monitor conditions affecting protein production or distribution, such as kidney disease, infections, or certain cancers.

Sample Collection and Preparation

A blood sample is drawn from a vein, typically in your arm. The blood is then processed to separate serum or plasma, which is sent to the lab for testing. The BCG dye method requires minimal preparation beyond standard blood collection.

Common Conditions Evaluated

This test can help diagnose or monitor conditions such as multiple myeloma (a cancer of plasma cells), liver disease (affecting albumin production), chronic kidney disease, or inflammatory disorders. It may also be used to screen for hidden protein abnormalities in routine blood work.