Rapid purification of EGFP, EYFP, and ECFP with high yield and purity.

Most current high throughput purification procedures for the green fluorescent protein (GFP) suffer from poor yields and low purity. An improved purification procedure that delivers highly pure protein (>95% homogeneity) in high yields (>70% of the initial fluorescent protein content) has been developed. The purification procedure requires only two steps: the cell lysate is heated to 60 degrees C for 4 min in ammonium sulfate and triethylamine, followed by hydrophobic interaction chromatography using isopropanol during the elution phase.