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R-10015

L-Thyroxine (ring-13C6)

Stable isotope standard for analytical research and method development.

Module Type
Stable Isotope Standards
Category
Hormones
CAS
720710-30-5
Unlabeled CAS
51-48-9
PubChem CID
155903785
Molecular Formula
C9[13C]6H11I4NO4
Molecular Weight
777.86
AI Isotope Property & Application AnalysisShow

Isotope Summary

Labels
13C6
Labeled atoms
6
Isotope positions
Confirmed in structure
Calculation reliability
High, based on explicit isotope structure

Mass & MS Parameters

Unlabeled exact mass
776.6867 Da
Labeled exact mass
782.706829 Da
Exact mass shift
6.020129 Da
Nominal mass shift
6
Ionm/zStatus
[M+H]+783.714105Theoretical
[M+Na]+805.696047Theoretical
[M+NH4]+800.740652Theoretical
[M-H]-781.699552Theoretical

Label Stability

Overall
Low risk
Calculation reliability
Medium, some information should be confirmed
  • Skeleton-bound 13C/15N labels are generally non-exchangeable under normal analytical handling.

Internal Standard Suitability

Rating
High
Chromatographic similarity
Expected high similarity
Natural isotope overlap
Low
  • Exact mass separation is 6.020129 Da; MS channel separation should be verified in the final method.
  • The unlabeled parent mass was derived from the isotope structure because a curated parent structure was not matched.
  • Overall suitability: High.

Recommended Applications

LC-MS/MS Quantitative Internal Standard
Recommended

LC-MS/MS Quantitative Internal Standard is classified as Recommended based on isotope mapping, mass separation, and label-stability rules.

Isotope Dilution Mass Spectrometry
Recommended

Isotope Dilution Mass Spectrometry is classified as Recommended based on isotope mapping, mass separation, and label-stability rules.

Metabolic Tracing
Not primary

Metabolic Tracing is classified as Not primary based on isotope mapping, mass separation, and label-stability rules.

Bioanalytical Method Development
Recommended

Bioanalytical Method Development is classified as Recommended based on isotope mapping, mass separation, and label-stability rules.

AI Interpretation

This analysis is based on isotope-aware structure data. The compound contains 13C6, with an exact mass shift of 6.020129 Da. Label stability is assessed as Low risk, and internal-standard suitability is High. These results support analytical method development and require experimental validation.

AI-assisted analytical guidance is intended for method-development support. Actual isotope stability, chromatographic behavior, fragmentation and MRM transitions should be experimentally validated.