The Thermo Scientific Pierce Fluorescent Protease Assay Kit measures total protease activity in samples, providing a means to assess the progress of protease isolation procedures or quantify protease contamination in biological samples.

This kit includes fluorescein-labeled casein as a substrate for assessing protease activity in a sample by either fluorescence resonance energy transfer (FRET) with a standard fluorometer or fluorescence polarization (FP) with capable instrumentation. FTC-Casein is native casein that has been labeled using a large molar excess of fluorescein isothiocyanate (FITC). Fluorescence properties of this heavily-labeled, intact protein substrate change dramatically upon digestion by proteases, resulting in a measurable indication of proteolysis.

Features of the Fluorescent Protease Assay Kit:

• Casein substrate—measure activity of any protease that cleaves casein into peptide fragments
• Trypsin standard—quantify protease activity relative to trypsin, a universally accepted reference
• Sensitive—1000 times more sensitive than assays that use unmodified forms of casein
• Simple and fast—test tube and microplate protocols are completed in less than one hour
• Homogenous—addition steps only; no separation, transfer or stop steps required
• Customizable—easily adapt time, temperature and pH to optimize sensitivity for proteases of interest

Applications:
• Assess functional integrity and overall progress of protease purification
• Quantify protease contamination in protein samples
• Characterize the activity of unusual proteases compared to trypsin
• Evaluate buffer conditions for their affects on protease function and activity

Additional Specifications:
• Substrate: fluorescein-labeled casein (FITC-casein); available separately as Part No. 23267
• Basis of assay: change in fluorescence resonance (FRET) or fluorescence polarization (FP)
• Measurement: instrument with fluorescein excitation and emission filters (485/538nm)

Related Products
Pierce™ Colorimetric Protease Assay Kit
FITC-Casein for Pierce™ Fluorescent Protease Assay Kit