Thermo Scientific Pierce TCEP-HCl is a potent, versatile, odorless, thiol-free reducing agent with broad application to protein and other research involving reduction of disulfide bonds. The unique compound is easily soluble and very stable in many aqueous solutions. TCEP reduces disulfide bonds as effectively as dithiothreitol (DTT), but unlike DTT and other thiol-containing reducing agents, TCEP does not have to be removed before certain sulfhydryl-reactive crosslinking reactions.

Thermo Scientific No-Weigh products are specialty reagents provided in a pre-aliquoted format. The pre-weighed packaging prevents the loss of reagent reactivity and contamination over time by eliminating the repetitive opening and closing of the vial. The format enables use of a fresh vial of reagent each time, eliminating the hassle of weighing small amounts of reagents and reducing concerns over reagent stability.

Features of TCEP-HCl:

• Odorless—Unlike DTT or BME, TCEP is odor-free, so it can reduce proteins conveniently on the bench; contributes to a healthier lab environment
• Specific—selective and complete reduction of even the most stable water-soluble disulfides over a wide pH range
• Simple—effective reduction at room temperature and pH 5 in less than five minutes
• Stable—it's inherent stability and resistant to air oxidation eliminates the need for any special precautions while handling or storing; non-volatile and non-reactive toward other functional groups found in proteins
• Efficient—For most applications, 5 to 50 mM TCEP provides sufficient molar excess to effectively reduce peptide or protein disulfide bonds within a few minutes at room temperature.
• Compatible—With TCEP, removal of the reducing agent is not necessary prior to most applications, (e.g. histidine-tagged protein purification, maleimide conjugations).

Considerations for use of TCEP:
• TCEP is generally very soluble in aqueous buffers at nearly any pH. Therefore, working concentrations and 10X stock solutions may be readily prepared in most aqueous buffers.
• TCEP is stable in aqueous, acidic, and basic solutions. When TCEP is dissolved directly in water, the resulting pH is approximately 2.5.
• TCEP is not particularly stable in phosphate buffers, especially at neutral or alkaline pH. Therefore, if TCEP is to be used in PBS buffers, prepare the working solution immediately before use.
• TCEP may be used as a substitute for DTT or 2-mercaptoethanol (2-ME) in sample loading buffer for SDS-PAGE; use a final concentration of 50 mM TCEP.
• Because TCEP is charged in solution, it is not compatible for use in isoelectric focusing.