cOmplete, EDTA-free Protease Inhibitor Cocktail

Tablets provided in glass vials




vial of 20 tablets (11873580001)
vial of 3 × 20 tablets (05056489001)




aqueous buffer: soluble


0.08 at 280 nm

shipped in

wet ice

storage temp.


General description

cOmplete, EDTA-free Protease Inhibitor Tablets, inhibit a broad spectrum of serine and cysteine proteases. In contrast to other cOmplete tablets they do not contain EDTA, leaving the stability and the function of metal-dependant proteins unaffected. The affinity purification of Poly-His-tagged fusion proteins using IMAC (Immobilized Metal Affinity Chromatography) is also facilitated (no dialysis necessary).
Due to the optimized composition of the tablets, they show excellent inhibition of serine and cysteine proteases, and are well suited for the protection of proteins isolated from animal tissues, plants, yeast, and bacteria. cOmplete, EDTA-free tablets, contains both irreversible and reversible protease inhibitors. Metallo- and aspartic proteases are not inhibited.

cOmplete EDTA-free Tablets are identical to cOmplete Tablets, the only difference being that no EDTA or other chelating (e.g. EGTA) agents are included.


Inhibits serine proteases, cysteine proteases. Does not inhibit metalloproteases.


cOmplete, EDTA-free is used for the inhibition of serine and cysteine proteases in bacterial, yeast, plant, and animal cell extracts.
cOmplete, EDTA-free Tablets, are used for the inhibition of proteolytic activity in large volumes (up to 50 ml) in which EDTA may interfere with protein stability (e.g., metal-containing proteins) or subsequent assays. Since EDTA interferes with IMAC (Immobilized Metal Affinity Chromatography), cOmplete, EDTA-free, is preferentially used in the isolation process of Poly-His-tagged fusion proteins.
If it is necessary to inhibit proteolytic activity in a smaller volume (up to 10 ml), we recommend to use cOmplete, Mini, EDTA-free.
cOmplete, EDTA-free Protease Inhibitor Cocktail has been used as a component of radioimmunoprecipitation assay (RIPA) lysis buffer for resuspending Chinese hamster ovary (CHO) cells. It has also been used as a component of resuspension buffer for HCT116 colorectal cancer cells.
cOmplete, EDTA-free Protease Inhibitor Cocktail has been used as as a component of
  • immunoprecipitation lysis buffer (IPLS) for lysis of human embryonic kidney cells 293 (HEK293T cells) for glutathione co-precipitation
  • radioimmunoprecipitation assay (RIPA) buffer for lysis of cells for western blotting
  • buffer A for the lysis of bacterial cells

Features and Benefits

Use cOmplete Protease Inhibitor Tablets to protect your proteins from a wide range of proteases. In just minutes, uninhibited proteolytic activity can degrade the protein you have spent days isolating. Each of these convenient water-soluble tablets contains a blend of protease inhibitors that inhibits proteolytic activity from most cell types, including animals, plants, yeast, and bacteria. No weighing or measuring is necessary, ensuring consistent results.

  • Easy-to-use: Simply drop a quick-dissolving tablet into your buffer.
  • Complete protection: Instantly protect your proteins against a broad range of proteases.
  • Flexible: Protect proteins in extracts from almost any tissue or cell, including animals, plants, yeast, bacteria, or fungi.
  • Safe: Choose non-toxic inhibitors that pose no risk to you or those around you.


Proprietary mixture of several protease inhibitors with broad inhibitory specificity.


Performance-tested with pancreas extract.

Physical form

Tablets in glass vials

Preparation Note

Working concentration: 1 tablet per 50 ml extraction solution
Working solution: Preparation of Working Solution

One cOmplete EDTA-free Protease Inhibitor Tablet is sufficient for the inhibition of the proteolytic activity in 50 ml extraction solution. When very high proteolytic activity is present, one tablet should be used for 25 ml extraction buffer. Tablets can be added directly to the extraction medium. Alternatively, a stock solution (25 X conc.) can be prepared.

Preparation of Stock solution (25 X conc.)

Dissolve one cOmplete EDTA-free tablet in 2 ml dist. water or in 2 ml 100 mM phosphate buffer, pH 7.0.
Storage conditions (working solution): The stock solution can be stored at 2 to 8 °C for 1 to 2 weeks, or at least 12 weeks at -15 to -25 °C.


Soluble in aqueous buffers, or add directly to extraction media. Alternatively, prepare 25x stock solutions in 2 ml water or 100 mM phosphate buffer, pH 7.0. Stock solution is stable for 1-2 weeks at 2 to 8 °C or at least 12 weeks at -15 to -25 °C; can be used in thiol-containing solutions at 15 to 25 °C.

Other Notes

For life science research only. Not for use in diagnostic procedures.

Legal Information

cOmplete is a trademark of Roche


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