This affinity‑purified chicken antibody specifically recognizes Streptococcal Protein G, a widely used Fc‑binding protein in antibody purification systems. Designed for sensitive detection of residual Protein G in downstream processing, it performs reliably in ELISA, Western blotting, and impurity profiling assays. The avian host species minimizes background from mammalian samples, supporting clean, high‑specificity detection across diverse matrices. CPG‑65A’s strong affinity and consistent purification make it a valuable reagent for bioprocess monitoring, regulatory compliance testing, and development of quantitative assays targeting Protein G impurities.