A novel fluorescent-based staining method for phosphoproteins analysis in SDS-PAGE gel employs Quercitin-aluminium complex formation that detects phosphoproteins among total proteins in a one dimension or two-dimensional gel. The sensitivity is 15-25ng of phosphoproteins detected in 90 minutes. Ideal for looking at total phosphoprotein profile in complex signal transduction pathways and building phosphoproteome. The results can be confirmed by dephosphorylation of the protein before running the gel. Alpha and beta chains of Casein can be used as controls.