Overview
TCEP Hydrochloride is a high-purity, odourless, non-thiol reducing agent widely used in biochemistry and molecular biology. Unlike thiol-based reducing agents such as DTT or β-mercaptoethanol, TCEP is more chemically stable in aqueous solution, does not require an inert atmosphere, and lacks the strong odour associated with thiol reagents.
It is commonly used to reduce disulfide bonds in proteins and peptides as a preparatory step for gel electrophoresis, mass spectrometry, and bioconjugation workflows. Because TCEP does not itself carry a free thiol group, it does not need to be removed before subsequent thiol-reactive labelling steps such as maleimide conjugation.
Key Features
Non-thiol reducing agent — odourless, more stable in aqueous solution than DTT or β-mercaptoethanol
Effective over a broad pH range; does not require an inert atmosphere
High purity (99.8% assay), suitable for reproducible research applications
Compatible with downstream thiol-reactive labelling (e.g. maleimide chemistry) without removal
Typical Applications
🧬
Protein Biochemistry
Disulfide bond reduction
🧪
Molecular Biology
Sample prep for SDS-PAGE, MS
🔗
Bioconjugation
Pre-labelling reduction step
🔬
General Research
Reducing agent in buffer systems
FAQs
❓ Why choose TCEP over DTT or β-mercaptoethanol?
TCEP is odourless, more stable in aqueous solution over time, works effectively across a broader pH range, and doesn't require an inert atmosphere to stay active — DTT and β-mercaptoethanol oxidise more readily and have a strong sulphurous smell. TCEP also lacks a free thiol group of its own, so it doesn't interfere with downstream thiol-reactive chemistry like maleimide labelling.
❓ Does TCEP need to be removed before maleimide conjugation?
No — this is one of TCEP's main practical advantages. Because TCEP reduces disulfides via a phosphine mechanism rather than thiol exchange, it doesn't carry a free thiol group itself and won't react with maleimide reagents, unlike DTT or β-mercaptoethanol which must be removed first.
❓ Why is this product classified as corrosive?
TCEP hydrochloride is acidic in solid form and causes severe skin burns and eye damage on contact (H314, Skin Corrosion Category 1B). This is a genuine hazard requiring proper PPE and handling — see the Safety Data tab before use.
Intended Use
⚠️ For research use only. Not for human, veterinary, diagnostic, or therapeutic use.
Chemical & Physical Information
| Product Name |
TCEP Hydrochloride |
| Catalogue Number |
ASC-8056 |
| CAS Number |
51805-45-9 |
| Chemical Formula |
C₉H₁₅O₆P · HCl |
| Formula Weight |
286.65 g/mol |
| Appearance |
White crystalline powder |
| Solubility |
Freely soluble in water — clear, colourless solution |
| Storage |
Store at +4°C |
| HS Tariff Code |
2931.4990 |
Mode of Action
TCEP reduces disulfide bonds (R-S-S-R) to free thiols (R-SH) via a phosphine-mediated mechanism, distinct from the thiol-exchange mechanism used by DTT and β-mercaptoethanol. This mechanism means TCEP itself does not contain a free thiol group and remains active over a broader pH range and for longer periods in solution.
Applications
| Category |
Typical Use |
| Protein biochemistry |
Reduction of disulfide bonds prior to SDS-PAGE, mass spectrometry, or other analytical workflows |
| Molecular biology |
Sample preparation for gel electrophoresis; protein/peptide reduction |
| Bioconjugation |
Reduction step preceding maleimide-based labelling and conjugation chemistry |
| General research |
General-purpose reducing agent in buffer systems and reaction mixtures |
Storage & Stability
Store at +4°C, tightly sealed, protected from moisture. Stable under recommended storage conditions.
Literature & References
| 1 |
Shafer DE, Inman JK, Lees A. Reaction of Tris(2-carboxyethyl)phosphine (TCEP) with Maleimide and α-Haloacyl Groups: Anomalous Elution of TCEP by Gel Filtration. Analytical Biochemistry. 2000;282(1):161–164. |
| 2 |
Han JC, Han GY. A procedure for quantitative determination of tris(2-carboxyethyl)phosphine, an odorless reducing agent more stable and effective than dithiothreitol. Analytical Biochemistry. 1994;220(1):5–9. |
⚠️ This substance is corrosive and classified as Dangerous Goods for transport. Read this section in full before handling or shipping. Full 16-section GHS SDS available —
support@ausamics.com
Hazard Identification (GHS 7th Ed / WHS 2023)
| Classification |
Skin Corrosion Category 1B |
| Signal Word |
Danger |
| Hazard Statement |
H314 — Causes severe skin burns and eye damage |
Handling & PPE
| Engineering Controls |
Fume hood or local exhaust ventilation required |
| PPE |
Chemical safety goggles/face shield, chemical-resistant gloves, lab coat; particulate respirator for bulk powder handling |
| Storage |
+4°C, tightly sealed, locked up, away from oxidising agents and bases |
Transport — Dangerous Goods
⚠️ This product IS classified as Dangerous Goods. Proper shipping name: Corrosive solid, acidic, organic, n.o.s. Class 8 (Corrosive), Packing Group II. DG-compliant packaging, labelling, and documentation are required for shipment — this differs from most other AuSaMicS products.
First Aid Summary
| Eyes |
Rinse cautiously with water for several minutes. Seek immediate medical attention — do not delay. |
| Skin |
Remove contaminated clothing immediately. Rinse skin with water/shower for at least 15 minutes. Seek medical attention. |
| Inhalation |
Remove to fresh air. Seek medical attention if symptoms occur. |
| Ingestion |
Do NOT induce vomiting. Rinse mouth, drink water, call the Poisons Information Centre immediately. |