Acetic acid-18O2
Acetic acid-18O2 (CAS 17217-83-3) is the doubly oxygen-18 labelled isotopologue of glacial acetic acid, with the molecular formula CH3C18O2H and a molecular weight of about 64.05 g/mol. Both carboxyl oxygen atoms carry the stable 18O isotope, giving an M+4 mass shift. Tech Serve Solutions supplies it at 95 atom % 18O as a corrosive, flammable research reagent used as a tracer and internal standard in mass spectrometry and mechanistic studies.
- Synonyms
- Acetic acid-18O2Acetic acid (18O2)Acetic acid-18O2, 95 atom % 18O(18O2)acetic acidGlacial acetic acid-18O2Ethanoic acid-18O2CAS 17217-83-3

Stable-isotope tracer for reaction mechanism studies
The 18O label at both carboxyl oxygens lets researchers trace the fate of oxygen atoms through esterification, hydrolysis and other carboxylic-acid reactions. It is widely used to distinguish bond-cleavage pathways and to probe oxygen exchange in mechanistic organic chemistry.
Internal standard for mass spectrometry
Its defined M+4 mass shift makes Acetic acid-18O2 a useful labelled internal standard for quantitative LC-MS and GC-MS workflows. The mass difference from natural acetic acid allows co-elution while remaining spectrally distinguishable.
Synthesis of 18O-labelled compounds
Acetic acid-18O2 serves as a labelled building block and acetylating reagent for preparing 18O-enriched acetate esters, intermediates and metabolites for research. The label can be carried into downstream products for tracking studies.
Isotope-labelling and metabolic research
As a stable, non-radioactive labelled acid, it supports tracer experiments in biochemical and metabolic studies where oxygen-18 incorporation is monitored. Stable-isotope labelling avoids the handling constraints associated with radioactive tracers.
| Molecular weight | 64.05 |
|---|---|
| Linear formula | CH3C18O2H |
| Boiling point | 117-118 °C(lit.) |
| Density | 1.116 g/mL at 25 °C |
| Refractive index | n20/D 1.3715(lit.) |
| Melting point | 16.2 °C(lit.) |


Hazard statements
- H226Flammable liquid and vapour
- H314Causes severe skin burns and eye damage
Precautionary statements
- P280Wear protective gloves, clothing and eye/face protection
- P305IF IN EYES
- P310Immediately call a POISON CENTER or doctor
| Protective equipment | Faceshields, full-face respirator (US), Gloves, Goggles, multi-purpose combination respirator cartridge (US), type ABEK (EN14387) respirator filter |
|---|---|
| Flash point | 40 °C / 104 °F |
| Transport (UN / ADR) | UN 2789 8/PG 2 |
| Water hazard class (WGK, DE) | 3 |
| Hazard codes (EU) | C |
| Risk statements (R) | 10-35 |
| Safety statements (S) | 16-26-36/37/39-45 |
Hazard information is provided for guidance. Always consult the product Safety Data Sheet (SDS), available on request, before handling.
| Isotopic Purity | 95 atom % 18O |
|---|---|
| Mol Wt | mol wt 63.86 by atom % calculation |
| Mass Shift | M+4 |
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 Acetic acid-18O2 used for?
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Acetic acid-18O2 is primarily used as a stable-isotope tracer and labelled internal standard. The 18O label at both carboxyl oxygens supports reaction-mechanism studies, mass-spectrometry quantification and the synthesis of 18O-enriched compounds in research settings.
What is the CAS number and molecular formula of Acetic acid-18O2?
+
The CAS number is 17217-83-3 and the molecular formula is CH3C18O2H, the doubly oxygen-18 labelled form of acetic acid. Its molecular weight is approximately 64.05 g/mol (about 63.86 by atom % calculation), with an M+4 mass shift.
What grade and purity does Tech Serve Solutions supply?
+
Tech Serve Solutions supplies Acetic acid-18O2 as a research-grade stable-isotope reagent with an isotopic enrichment of 95 atom % 18O. We do not represent it as USP, BP or EP pharmacopoeial grade. Detailed specifications are confirmed against the certificate of analysis for each batch.
What are the safety and handling hazards of Acetic acid-18O2?
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It is classified as a flammable liquid and vapour (H226) that causes severe skin burns and eye damage (H314); the GHS signal word is Danger, with pictograms GHS02 and GHS05. Handle it away from ignition sources using gloves, goggles and face protection, and consult the SDS before use. It has a flash point of about 40 degrees C and a German water-hazard class (WGK) of 3.
How is Acetic acid-18O2 packed, shipped and exported?
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It is supplied in sealed, isotope-grade containers appropriate to the order quantity, with batch documentation. As a Class 8 corrosive shipped under UN 2789 (packing group II), it is packed and labelled to applicable dangerous-goods regulations for compliant global export.
How do I request a sample or quote for Acetic acid-18O2?
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Contact Tech Serve Solutions with your required quantity, isotopic specification and destination country, and our team will respond with availability, documentation and a quotation. Sample requests for evaluation can be discussed at the time of enquiry.
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