Direct chemiluminescent imaging detection of serum proteins in polyacrylamide gels Original Research Article

A novel chemiluminescence (CL)-based imaging method capable of directly detecting proteins in polyacrylamide gels after electrophoresis is proposed. The method is rapid and sensitive compared to the traditional Coomassie brilliant blue R250 (CBB-R250) staining method. Several proteins, including haptoglobin (Hp) (Hp1-1, Hp2-2 and Hp2-1), human serum albumin (HSA), as well as some other proteins present in human serum, have been sensitively detected by the proposed method using hemoglobin (Hb) as probe. The CL imaging conditions, including luminescent reagents, exposure time, and Hb concentration, have been optimized. Under the optimal conditions, detection limits were 0.22 μg ml−1 for Hp and 0.15 μg ml−1 for HSA. Comparing with the traditional method of CBB-R250 staining, the sensitivity of the proposed method has been improved over ten times for Hp and HSA and the analysis time decreased for about seventy times.