Detection of fluorescence dye-labeled proteins in 2-D gels using an Arthur(TM) 1442 multiwavelength fluoroimager

Labeling of proteins with SYPRO (R) orange, SYPRO Red, and SYPRO Rubp after 2-D polyacrylamide gel electrophoresis (PAGE) using plastic-backed immobil ized pH gradient (IPG) strips and precast SDS polyacrylamide gels was teste d. Protein spots were detected using an Arthur (TM) 1442 Multiwavelength Fl uoroimager. The labeling methods described allow detection of proteins both after isoelectric focusing (IEF) and PAGE with a sensitivity higher than o l comparable fo standard silver staining methods. lit addition to the post- labeling methods mentioned above, pre-labeling with the cysteine-specific f luorophore monobromobimane before 2-D PAGE is a sensitive fast, and cost-ef fective alternative to existing staining protocols.