Quick, colorimetric assay for measuring inorganic phosphate (Pi) from ATP/GTP hydrolysis or other sources. Homogeneous assay, ideal for high-throughput screening (HTS) applications.

• End point measurement of ATP and GTP hydrolysis catalyzed by ATPases and GTPases
• High-throughput discovery of ATPase/GTPase inhibitors
• Measure the Pi content of a biological buffer or solution

Kit contents (960 assays)

• CytoPhos™ reagent
• Phosphate standard

Equipment & materials required

• Spectrophotometer, end-point setting, Absorbance 650 nm

The ATPase/GTPase end-point assay is a rapid and economical way to measure inorganic phosphate (Pi) generated during the enzymatic hydrolysis of ATP or GTP. The assay is based upon a malachite green/molybdate colorimetric change (yellow to green), measured at 650 nm.

Key characteristics

• Quantitative assay
• Detection method: end-point absorbance 650 nm
• Assay volume: 100 µl
• Sensitivity: 0.01 – 1.0 nmoles Pi (100 ul vol.)
• Timeframe: Approximately 2 hours