Protein Quantitation in 2-D Gels Using Fluorescence with Water Raman as an Internal Standard

We have developed a method to enhance fluorescence quantification in two-dimensional gel electrophoresis using the inherent Raman scattering of water as an internal standard. We demonstrate this water internal standard (WIS) method using quantitative comparisons of commercially available protein standards that were either covalently tagged or passively stained with fluorescent tags. Thus, WIS opens up the possibility of enhancing intra- and intergel quantitative comparisons.