Pierce™ Colorimetric Protease Assay Kit

The Thermo Scientific Pierce Colorimetric 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 uses fully succinylated casein as a substrate for the assay. Hydrolysis of this substrate in the presence of protease results in the release of peptide fragments with free amino-terminal groups. These peptides are reacted with trinitrobenzene sulfonic acid (TNBSA), followed by measurement of the absorbance increase that results from the formation of yellow colored TNB-peptide adducts.

Features of the Colorimetric 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: succinylated casein (not available separately)
• Basis of assay: detection of primary amines resulting from proteolysis
• Detection reagent: trinitrobenzene sulfonic acid (TNBSA)
• Measurement: absorbance at 450nm (plate reader or spectrophotometer)

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