Paraoxon-ethyl
Paraoxon-ethyl (CAS 311-45-5), with the molecular formula O2NC6H4OP(O)(OC2H5)2 and a molecular weight of 275.20 g/mol, is a yellow oily liquid. It is a potent inhibitor of acetylcholinesterase and is primarily utilized as an enzyme substrate in biochemical research and assays. Its specific activity makes it valuable for studying esterase enzymes and related biological processes. Tech Serve Solutions supplies this compound for research and development purposes.
- IUPAC
- O,O-Diethyl O-(4-nitrophenyl) phosphate,Diethyl p-nitrophenyl phosphate,Paraoxon-ethyl,Paraoxon
- Synonyms
- O,O-Diethyl O-(4-nitrophenyl) phosphateDiethyl p-nitrophenyl phosphateParaoxonDiethyl p-nitrophenyl phosphorothioate

Enzyme Substrate
Paraoxon-ethyl serves as a substrate for studying the activity of esterase enzymes, particularly acetylcholinesterase. It allows researchers to quantify enzyme kinetics and inhibition.
Biochemical Research
Utilised in cell biology and biochemical studies to investigate enzyme mechanisms and biological pathways affected by esterase activity. Its well-defined properties aid in reproducible experimental outcomes.
Assay Development
Applied in the development and validation of analytical assays for detecting or quantifying specific enzyme activities. This includes its use in environmental monitoring or toxicological studies where esterase inhibition is a factor.
| Molecular weight | 275.20 |
|---|---|
| Linear formula | O2NC6H4OP(O)(OC2H5)2 |
| Assay | ≥90% |
| Form | oil |
| Colour | yellow |
| Density | 1.274 g/mL at 25 °C(lit.) |
| Refractive index | n20/D 1.51(lit.) |
| Storage temperature | 2-8°C |


Hazard statements
- H300Fatal if swallowed
- H310Fatal in contact with skin
- H330Fatal if inhaled
- H400Very toxic to aquatic life
Precautionary statements
- P260Do not breathe dust, fume, gas, mist, vapours or spray
- P264Wash thoroughly after handling
- P273Avoid release to the environment
- P280Wear protective gloves, clothing and eye/face protection
- P284Wear respiratory protection
- P301IF SWALLOWED
| Protective equipment | Eyeshields, Faceshields, full-face respirator (US), Gloves, multi-purpose combination respirator cartridge (US), type ABEK (EN14387) respirator filter |
|---|---|
| Transport (UN / ADR) | UN 2810 6.1/PG 1 |
| Water hazard class (WGK, DE) | 3 |
| Hazard codes (EU) | T+,N |
| Risk statements (R) | 26/27/28-50 |
| Safety statements (S) | 36/37/39-45-61 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
| Gene Information | human ... PON1(5444) |
|---|
Documentation
Every batch ships with a Certificate of Analysis covering assay, identity and purity; the grade is confirmed against your enquiry. Safety Data Sheets and technical data sheets are available on request.
Supply & logistics
Samples for technical evaluation; bulk MOQ by grade and packaging. In-stock material ships in 7–10 working days, worldwide, with full export documentation.
What is Paraoxon-ethyl used for?
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Paraoxon-ethyl is used as an enzyme substrate for studying esterase enzymes, particularly acetylcholinesterase, in biochemical research and assay development.
What is the CAS number and chemical formula for Paraoxon-ethyl?
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The CAS number is 311-45-5, and the chemical formula is O2NC6H4OP(O)(OC2H5)2.
What grade and purity does Tech Serve Solutions supply?
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Tech Serve Solutions supplies Paraoxon-ethyl with an assay of ≥90%. This product is intended for research and development use and is not represented as USP, BP, EP, or pharmacopoeia grade.
How should Paraoxon-ethyl be handled safely?
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Paraoxon-ethyl is highly toxic and requires extreme caution. Handle with appropriate personal protective equipment, including eyeshields, gloves, and a full-face respirator. Avoid inhalation, ingestion, and skin contact. Store in a cool, well-ventilated area, adhering to GHS hazard statements H300, H310, H330, and H400.
Is Paraoxon-ethyl a controlled substance?
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The provided data does not indicate that Paraoxon-ethyl is a controlled substance. However, due to its high toxicity, its handling and use may be subject to specific regulations.
How is Paraoxon-ethyl packed and shipped?
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Paraoxon-ethyl is shipped as UN 2810, Hazard Class 6.1, Packing Group I, indicating it is a toxic solid or liquid, n.o.s. It is exported globally by Tech Serve Solutions following stringent safety and regulatory protocols.
How can I request a sample or quote for Paraoxon-ethyl?
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To request a sample or a quote, please contact the Tech Serve Solutions sales team via our website or directly through your account manager, providing the product name and CAS number (311-45-5).
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