All of the following are used for the detection of protein tumor markers except?

• A. Electrophoresis
• B. Hybrid capture assay
• C. ELISA
• D. Agglutination assays

Answer: (B)

Protein tumor marker detection centers on identifying the protein itself, usually through antibodies or by separating and visualizing the protein. A hybrid capture assay, in contrast, targets nucleic acids—forming RNA-DNA hybrids to detect specific DNA or RNA sequences. That makes it a method for genetic material, not for proteins, so it doesn’t apply to detecting protein tumor markers. The other methods fit protein detection: electrophoresis separates proteins by size and charge to reveal patterns, ELISA uses antibody binding with a detectable signal to quantify a specific protein, and agglutination assays rely on antibody-coated particles clumping in the presence of the target protein.