Pierce™ Colorimetric Protease Assay Kit
Pierce™ Colorimetric Protease Assay Kit
Thermo Scientific™

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深入閱讀
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產品號碼Quantity
23263250 Test Kit
產品號碼 23263
價格 (TWD)
16,125.00
Online offer
Ends: 31-Mar-2026
21,500.00
您節省 5,375.00 (25%)
Each
新增至購物車
Quantity:
250 Test Kit
Request bulk or custom format
價格 (TWD)
16,125.00
Online offer
Ends: 31-Mar-2026
21,500.00
您節省 5,375.00 (25%)
Each
新增至購物車

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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For Research Use Only. Not for use in diagnostic procedures.
規格
AssayProtease Assay
For Use With (Application)Absorbance
For Use With (Equipment)Microplate Reader
Product LinePierce
Product TypeProtein Activity Assay
Quantity250 Test Kit
SubstrateCasein
Substrate PropertiesProtein-Based Substrate
Substrate TypeProtease Substrate
Sufficient For250 Microplate Assays
TargetProteases
Detection MethodColorimetric
Immunoassay Kit Format96-well Plate
Unit SizeEach
內容物與存放
Sufficient For: 250 microplate assays using a standard plate reader (absorbance at 450 nm)
• Succinylated Casein, 5 x 10 mg
• TNBSA Solution, 2 mL
• TPCK Trypsin Standard, 50 mg
• Borate Buffer Pack (makes 500 mL), 1 pack

Store at 4°C.

常見問答集 (常見問題)

In the Colorimetric Protease Assay Kit (Cat. No. 23263), my standard curve is not linear. Why?

Check the scale used for your X-axis. A logarithmic scale should be used for the X-axis (protease enzyme concentration) rather than a linear scale.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

In the Colorimetric Protease Assay Kit (Cat. No. 23263), my sample absorbance values are lower than smallest trypsin or other protease standard values. Why?

It could be that the sample protease activity is low relative to the range of dilutions used for the standard curve. You can prepare and use additional standard dilutions to ensure that the full range of assay sensitivity is utilized. Alternatively, the sample protease activity is low relative to the protease used to make standard curve. You can prepare a standard curve using the known amounts of the specific protease being tested.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

In the Colorimetric Protease Assay Kit (Cat. No. 23263), all of my sample absorbance values for non-trypsin proteases are low. What can I do?

There are two potential causes for low absorbance values in the unknown samples. The first being that pH and other buffer conditions were not optimal for the protease being tested. You can repeat the assay using buffer conditions that are optimal for the protease being tested and used to make standard curve. Secondly, it is possible that the protease being tested digests the casein substrate more slowly or less fully than the trypsin standard for which the default assay method was developed. You can perform the digestion step for >20 minutes (e.g., 40 mins); if necessary, also perform the TNBSA development step for longer. You can also use the specific substrate for the protease being tested.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

Do you offer any protein assays that are protein specific?

We offer several “specialty” protein assays including: Protease assay kits (Cat. Nos. 23263 and 23266), Glycoprotein Carbohydrate Estimation Kit (Cat. No. 23260), Phosphoprotein Phosphate Estimation Kit (Cat. No. 23270), Quantitative Peroxide assay kits (Cat. Nos. 23280 and 23285), and Easy-Titer Assay kits for IgG and IgM.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.