1,3,5,7-Octamethyl-d24 cyclotetrasiloxane | CAS 83561-66-4

Overview

1,3,5,7-Octamethyl-d24 cyclotetrasiloxane | CAS 83561-66-4  is a high-purity, stable isotope-labeled siloxane compound widely used in advanced analytical laboratories and research environments. It is the fully deuterated analog of octamethylcyclotetrasiloxane (commonly known as D4), in which all hydrogen atoms in the methyl groups are replaced with deuterium (²H). This isotopic substitution results in a predictable and measurable mass shift, making the compound particularly valuable for quantitative mass spectrometry and isotopic tracing applications.

At ResolveMass Laboratories Inc., this material supports highly accurate analytical workflows, especially in laboratories focused on trace analysis, environmental monitoring, silicone characterization, and method validation.

CHEMICAL INFORMATION

• Chemical Name: 1,3,5,7-Octamethyl-d24 Cyclotetrasiloxane

• CAS Number: 83561-66-4

• Molecular Formula: C8D24O4Si4

• Molecular Weight: 320.76 g/mol

• Structure: Cyclic tetramer composed of alternating silicon and oxygen atoms (Si–O–Si–O ring), with eight fully deuterated methyl groups attached to silicon.

The compound consists of a four-membered siloxane ring, often described as a cyclic tetrasiloxane. Each silicon atom is bonded to two oxygen atoms (forming the ring) and two CD3 groups. The complete replacement of hydrogen with deuterium increases the molecular mass by 24 atomic mass units relative to the non-labeled analog, enabling clear differentiation in mass spectrometric analysis.

PHYSICAL AND CHEMICAL PROPERTIES

1,3,5,7-Octamethyl-d24 Cyclotetrasiloxane is typically supplied as a clear, colorless liquid at room temperature. Like other cyclic volatile methylsiloxanes (VMS), it exhibits:

• Low polarity

• Hydrophobic character

• Low surface tension

• Moderate volatility

• Limited water solubility

• Good solubility in most organic solvents

The deuterium substitution does not significantly alter the compound’s chemical reactivity or physical handling characteristics compared to its non-deuterated counterpart. However, the isotopic mass shift provides a strong analytical advantage in spectrometric techniques.

ANALYTICAL APPLICATIONS  of  1,3,5,7-Octamethyl-d24 cyclotetrasiloxane | CAS 83561-66-4

The primary value of 1,3,5,7-Octamethyl-d24 Cyclotetrasiloxane lies in analytical science. Its stable isotope labeling makes it an ideal internal standard and reference compound.

1. Mass Spectrometry Internal Standard
The +24 Da mass difference ensures baseline separation from native siloxanes in GC-MS and LC-MS methods. It is frequently used to:

• Correct for matrix effects

• Improve quantitation accuracy

• Compensate for injection variability

• Monitor recovery efficiency

Because its chemical behavior closely mirrors that of non-labeled siloxanes, it co-extracts and co-elutes in a comparable manner while remaining analytically distinguishable.

2. Environmental Monitoring
Volatile cyclic siloxanes are common environmental contaminants originating from personal care products, industrial processes, and silicone materials. The deuterated analog is valuable in environmental method development for air, water, sediment, and biota studies.

3. Extractables and Leachables Studies
Siloxanes are frequently detected in extractables and leachables (E&L) investigations, especially in pharmaceutical packaging, medical devices, and silicone components. This isotopically labeled compound is used to validate detection methods and confirm siloxane quantitation in complex matrices.

4. Silicone Polymer Research
In silicone manufacturing and polymer chemistry, this compound supports kinetic studies, degradation profiling, and mechanistic investigations of siloxane ring-opening or polymerization processes.

ADVANTAGES OF DEUTERATED ANALOGS

Using a fully deuterated analog provides several critical benefits:

• Precise mass shift for clear identification

• Minimal chromatographic deviation from native compound

• Chemical stability during analytical workflows

• Reliable calibration performance

• Enhanced reproducibility in regulated laboratory environments

The isotopic integrity ensures the compound behaves similarly to the analyte of interest while maintaining distinct spectral properties.

QUALITY AND ANALYTICAL PERFORMANCE

For analytical laboratories, purity and isotopic enrichment are critical performance parameters. High chemical purity ensures minimal background interference, while high deuterium incorporation ensures accurate mass differentiation. Analytical validation may include:

• NMR confirmation of deuterium incorporation

• High-resolution mass spectrometry verification

• Chromatographic purity assessment

At ResolveMass Laboratories Inc., materials are selected and evaluated to support advanced quantitative workflows where accuracy, traceability, and reliability are essential.

RESEARCH AND INDUSTRY APPLICATION AREAS

• Environmental analytical laboratories

• Pharmaceutical analytical development

• Extractables and leachables testing

• Silicone material research

• Polymer chemistry studies

• Academic isotope tracing research

• Method validation and calibration development

TECHNICAL SIGNIFICANCE

1,3,5,7-Octamethyl-d24 Cyclotetrasiloxane represents a specialized analytical standard designed for laboratories requiring highly controlled and traceable measurement of volatile siloxanes. Its structural similarity to native D4 combined with a well-defined isotopic mass shift enables robust quantitative methods in complex matrices.

As analytical instrumentation becomes increasingly sensitive, isotopically labeled standards such as this compound play a critical role in maintaining method accuracy and regulatory compliance. For laboratories focused on high-precision mass spectrometry and siloxane analysis, this compound provides a reliable and technically sound solution.

Learn more about Deuterated Chemicals,

• Deuterated Polymers: A Cornerstone Guide to Synthesis, Applications, and Future Trends
• Availability of All the Deuterated Chemicals at ResolveMass Laboratories Inc. 
• ResolveMass Laboratories: Leading Deuterated Chemical Synthesis Company in the United States.
• Deuterated Internal Standards for LC-MS: Selection & Custom Synthesis 
• How to Choose the Right Deuterated Labelled Chemical Synthesis Company in Canada 
• How to Choose the Right Deuterium Labelled Compounds Supplier for Your Lab 
• Deuterium-Labelled Compounds — Synthesis, Applications & Ordering 
• Custom Synthesis of Deuterated Chemicals