Procedures from samples to sulfur isotopic data: A review

Area of Science:

• Geochemistry
• Environmental Science
• Analytical Chemistry

Background:

• Sulfur isotopes are crucial for scientific inquiry, with advanced techniques emerging in recent decades.
• Diverse sulfur speciation and isotopic analyses are common, but methods vary significantly.
• Inconsistencies in published sulfur isotope data can arise from multifarious sampling and measurement techniques.

Purpose of the Study:

• To review and consolidate various sulfur isotopic analysis methods.
• To provide guidance on sampling, laboratory work, and instrumental analysis.
• To reduce operational inhomogeneity and ensure the fidelity of sulfur isotopic data.

Main Methods:

• Comprehensive literature review of sulfur isotope analysis methodologies.
• Analysis from the perspectives of sampling, laboratory procedures, and instrumental techniques.
• Focus on identifying potential sources of error and proposing best practices.

Main Results:

• External contamination and sulfur species transformation must be prevented during all analytical stages.
• Verification of conversion rates and isotopic fractionation using standard samples is essential.
• Unification of methods to ensure the absence of isotopic fractionation and long-term monitoring of standards are recommended.

Conclusions:

• This review offers detailed insights into sulfur isotope sampling, laboratory operations, and measurement techniques for improved laboratory practices.
• While microanalysis and molecular studies are advancing, elemental analysis/continuous flow-gas source stable isotope ratio mass spectrometry remains widely utilized.
• Advancements in sulfur isotope measurement will drive innovation in scientific understanding through sulfur proxies.