Call 408.493.1800 | Fax 408.493.1801 | Toll Free 800.891.9699 (US Only) | Email: [email protected]

Cathepsin B Activity Fluorometric Assay Kit

based on 9 citations in multiple journalsCathepsin B Activity Fluorometric Assay Kit94.2 4
Catalog #: K140

Product Details

Cat # +Size K140-100
Size 100 assays
Detection Method Fluorescence (Ex/Em 400/505) and fluorometer
Species Reactivity Mammalian
Applications Detects alternative proteolytic enzymes such as the lysosomal cathepsin proteases that can initiate or propagate proapoptotic signals.
Features & Benefits • Simple one-step procedure; takes only 1-2 hours
• Fast and convenient
• Cathepsin-B assay is straightforward, and can be adapted to 96-well plate assays.
Kit Components • CB Cell Lysis Buffer
• CB Reaction Buffer
• CB Substrate Ac-RR-AFC (10 mM)
• CB Inhibitor (1 mM)
Storage Conditions -20°C
Shipping Conditions Gel Pack
USAGE For Research Use Only! Not For Use in Humans.


Apoptosis can be mediated by mechanisms other than the traditional caspase-mediated cleavage cascade. There is growing recognition that alternative proteolytic enzymes such as the lysosomal cathepsin proteases may initiate or propagate proapoptotic signals. Cathepsins are lysosomal enzymes that are also used as sensitive markers in various toxicological investigations. The Cathepsin-B Activity Assay kit is a fluorescence-based assay that utilizes the preferred cathepsin-B substrate sequence RR labeled with AFC (amino-4-trifluoromethyl coumarin). Cell lysates or other samples that contain cathepsin-B will cleave the synthetic substrate RR-AFC to release free AFC. The released AFC can easily be quantified using a fluorometer or fluorescence plate reader.

Why buy BioVision Products?
Global Presence
Technical Support
BioVision aims to provide our customers innovative tools for accelerating drug discovery and biological research. BioVision offers >8,000 products including the most comprehensive array of assay kits for key targets in Metabolic pathways.
BioVision is committed to providing the highest quality products at a competitive price.
We have a broad network of global distributors who are ready to address your research needs and ensure fast delivery.
Our highly trained Technical Support team provides comprehensive product support and is dedicated to resolving your issues quickly and efficiently.
How does the inhibitor provided with the kit work?
The inhibitor binds tightly to the active site of the enzyme and is a potent inactivator of Cathepsin B.
How should tissue lysates be prepared?
We have never tested this kit on tissue samples. However, if you want to test, you could homogenize the tissue in Cell Lysis buffer, preferably using a Dounce homogenizer. Centrifuge the lysate and use the supernatant for the assay.
Will this kit work with mouse or rat samples?
This kit is compatible with all mammalian samples including mouse and rat.
Can we interchange the buffer from this kit with K143?
Each buffer is of different composition and they cannot be used 
Can the kit work on bacteria or yeast cells?
The kit has been standardized for mammalian cells only
What is the exact volume of sample required for this assay?
There is no specific volume we can recommend for the amount any sample to be used since it is completely sample concentration and quality based. You have to do a pilot expt with multiple sample volumes to determine the optimal volume which gives a reading within the linear range of the standard curve. Please refer to the citations for this product to see what other clients have used with similar sample types.
Do you have trial sizes of this kit?
Unfortunately, we do not have trial sizes of this kit available. However, if you are based in the US or Canada, we will give you a 10% off list price introductory discount on its purchase price. If you are based out of this area please contact yopur regional BioVision distributor.
What is the shelf life of this kit?
The expiry date is typically 1 year from the date of shipment
Can we purchase individual components of this kit?
Yes, you can purchase any of the kit's components without the whole kit. Please refer to the component Cat #s mentioned on the datasheet for ordering.
Can we use an alternate buffer for sample preparation (cell lysis, sample dilutions etc)?
Our assay buffers are optimized for the reactions they are designed for. They not only contain some detergents for efficient lysis of your cells/tissue, but also contain some proprietary components required for the further reactions. Therefore, we highly recommend using the buffers provided in the kit for the best results.
Liu et al., Autophagy-Lysosome Pathway in Renal Tubular Epithelial Cells Is Disrupted by Advanced Glycation End Products in Diabetic Nephropathy.   J. Biol. Chem., Aug 2015; 290: 20499 - 20510.
Liu et al., Urinary proteins induce lysosomal membrane permeabilization and lysosomal dysfunction in renal tubular epithelial cells. Am J Physiol Renal Physiol, Mar 2015; 308: F639 - F649.
Toomey et al., Cathepsin B Regulates the Appearance and Severity of Mercury-Induced Inflammation and Autoimmunity. Toxicol. Sci., Dec 2014; 142: 339 - 349.
Yang et al., Overexpression of Vascular Endothelial Growth Factor in the Germinal Matrix Induces Neurovascular Proteases and Intraventricular Hemorrhage. Science Translational Medicine, Jul 2013; 5: 193ra90.
Yi-Hsiang Liao et al., HMG-CoA reductase inhibitors activate caspase-1 in human monocytes depending on ATP release and P2X7 activation. J. Leukoc. Biol., Feb 2013; 93: 289 - 299.
For more citations of this product click here