All Photos(1)




Protease Colorimetric Detection Kit

Sign Into View Organizational & Contract Pricing

storage temp.



The Protease Colorimetric Detection Kit is designed for the accurate quantitation of protease activity. The method is based on the cleavage of casein into trichloroacetic acid-soluble peptides containing tyrosine and tryptophan residues. These peptides react with Folin-Ciocalteu reagent to give a characteristic blue color that can be measured at 660 nm.


Detection limit: 0.1 unit/ml (approx. 2 μg) trypsin with a 10 minute incubation time.


For greater sensitivity or for detection of trace protease activity, the Protease Fluorescent Detection kit (PF0100) is recommended.


Supplied with sufficient reagents to perform 200 one mL assays.

Analysis Note

This kit has been tested for detection of all four proteolytic classes (serine, apartic, cysteine and metalloproteinases).

Kit Components Only

Product No.

  • Protease detection substrate (casein) 20 x 10

  • Folin & Ciocalteu's phenol reagent 10 mL

  • Sodium carbonate solution 125 mL

  • Enzyme diluent 125 mL

  • Tyrosine standard solution 1 mL

  • Protease from Bacillus polymyxa 1 g

  • Trichloroacetic acid (TCA) solution 5 mL

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

Already Own This Product?

Documents related to the products that you have purchased in the past have been gathered in the Document Library for your convenience.

Visit the Document Library

Difficulty Finding Your Product Or Lot/Batch Number?

Product numbers are combined with Pack Sizes/Quantity when displayed on the website (example: T1503-25G). Please make sure you enter ONLY the product number in the Product Number field (example: T1503).


Product Number
Pack Size/Quantity

Additional examples:





enter as 1.000309185)

Having trouble? Feel free to contact Technical Service for assistance.

Lot and Batch Numbers can be found on a product's label following the words 'Lot' or 'Batch'.

Aldrich Products

  • For a lot number such as TO09019TO, enter it as 09019TO (without the first two letters 'TO').

  • For a lot number with a filling-code such as 05427ES-021, enter it as 05427ES (without the filling-code '-021').

  • For a lot number with a filling-code such as STBB0728K9, enter it as STBB0728 without the filling-code 'K9'.

Not Finding What You Are Looking For?

In some cases, a COA may not be available online. If your search was unable to find the COA you can request one.

Request COA

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service