cOmplete Protease Inhibitor Cocktail

Tablets provided in glass vials

protease inhibitor tablet




vial of 20 tablets (11697498001)
vial of 3 × 20 tablets (11836145001)



optimum pH



aqueous buffer: soluble


0.08 at 280 nm

shipped in

wet ice

storage temp.


General description

cOmplete Protease Inhibitor Tablets inhibit a broad spectrum of serine, cysteine, and metalloproteases, as well as calpains. Due to the optimized composition of the tablets, they show excellent inhibition effects, and are well suited for the protection of proteins isolated from animal tissues, plants, yeast, and bacteria. cOmplete tablets contain EDTA and both irreversible and reversible protease inhibitors.


Mixture of several protease inhibitors with broad inhibitory specificity. For the inhibition of serine, cysteine, and metalloproteases in bacterial, mammalian, yeast, and plant cell extracts.


cOmplete Protease Inhibitor Cocktail has been used as a component of
  • lysis buffer for the homogenisation of rat cavernosal smooth muscle (CSM) for obtaining membranous and cytosolic fractions
  • cold buffer A for preparing cytosolic and nuclear extracts
  • lysis buffer for homogenisation of tissues for determining protein expression by western blot
  • phosphate buffered saline (PBS) for the lysis of rat retinae for enzyme linked immunosorbent assay (ELISA)

cOmplete is used for the inhibition of serine, cysteine, and metalloproteases in bacterial, mammalian, yeast, and plant cell extracts.
cOmplete contains both reversible and irreversible protease inhibitors. Therefore, we recommend the addition of cOmplete to all stock buffers and solutions normally protected with protease inhibitors, and not  just during the initial purification steps.
cOmplete contains EDTA (1 tablet yields a  1 mM EDTA solution in 50 ml). Therefore, the extraction buffer should not contain divalent cations like Ca2+ , Mg2+, or Mn2+, otherwise the inhibition of the metalloproteases might be incomplete. If the protein of interest will be purified by IMAC (Immobilized Metal Affinity Chromatography), for example, Poly-His-tagged recombinant proteins, EDTA has to be eliminated (e.g., by dialysis) prior to the chromatography.
Alternatively, the product cOmplete EDTA-free can be used. These tablets are identical to cOmplete, with the exception that no EDTA or other chelating agent is  present.
cOmplete Tablets inhibit proteolytic activity in large extraction volumes (up to 50 ml). If you are working with smaller volumes (up to 10 ml), we recommend to use cOmplete, Mini. The composition of the cOmplete, Mini Tablet is identical to the normal cOmplete Tablet.

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.
  • Suitable for IMAC purification: Purify poly-histidine tagged proteins with cOmplete His-Tag Purification Resin.


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 Protease Inhibitor Tablet is sufficient for the inhibition of the proteolytic activity in 50 ml extraction solution. If 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 Protease Inhibitor tablet in 2 ml dist. water or in 2 ml 100 mM phosphate buffer, pH 7.0. The stock solution can also be prepared in 10 mM Tris buffer, pH 7.2 to 7.5.
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 to 2 weeks at 2 to 8 °C or at least 12 weeks at -15 to -25 °C; can also be used in thiol-containing solutions at 15 to 25 °C.

Other Notes

Inhibition efficiency is quickly and sensitively tested with the Universal Protease Substrate. For life science research only. Not for use in diagnostic procedures.

Legal Information

cOmplete is a trademark of Roche


NONH for all modes of transport

Certificate of Analysis
Certificate of Origin
Chengfeng Xiao et al.
Developmental neurobiology, 67(4), 438-455 (2007-04-20)
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Ethanol-induced erectile dysfunction and increased expression of pro-inflammatory proteins in the rat cavernosal smooth muscle are mediated by NADPH oxidase-derived reactive oxygen species
Leite LN, et al.
European Journal of Pharmacology, 804, 82-93 (2017)
Chronic ethanol consumption increases vascular oxidative stress and the mortality induced by sub-lethal sepsis: Potential role of iNOS
Ceron CS, et al.
European Journal of Pharmacology, 825, 39-47 (2018)
Modulation of alpha-adrenoceptor signalling protects photoreceptors after retinal detachment by inhibiting oxidative stress and inflammation
Li T, et al.
British Journal of Pharmacology, 176(6), 801-813 (2019)
Tamara Aleksic et al.
Cell communication and signaling : CCS, 6, 8-8 (2008-10-28)
Notch signalling is essential for the development and maintenance of the colonic epithelium. Its inhibition induces a differentiation phenotype in vivo and reduces adenomas in APCmin mice. Whether Notch signals are also required in colorectal cancer (CRC) has remained elusive....
Get maximum protection after protein isolation by using protease and phosphatase inhibitor cocktail tablets from Roche.
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It is possible dissolve 1 tablet in as little as 2 ml double distilled Water, results in a 25x stock solution, without difficulty.
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