"Do it yourself" reference materials for δ13C determinations by isotope ratio mass spectrometry

Area of Science:

• Geochemistry
• Analytical Chemistry
• Environmental Science

Background:

• Stable isotope analysis is crucial for various scientific disciplines.
• Accurate calibration of instruments requires reliable reference materials.
• Existing reference materials can be expensive or difficult to prepare.

Purpose of the Study:

• To develop an inexpensive and straightforward method for preparing organic reference materials for stable isotope analysis.
• To create custom reference materials that closely match international measurement standards.
• To enable routine, precise daily calibration of isotopic composition.

Main Methods:

• Blending isotope-enriched and isotope-depleted organic compounds (e.g., glucose).
• Matching the isotopic composition of the blend to international standards (e.g., NBS 19, L-SVEC).
• Dispensing prepared solutions into tin capsules for combustion in conventional isotope analysis systems.

Main Results:

• A straightforward and cost-effective method for preparing organic reference materials was successfully demonstrated.
• Blended glucose samples accurately matched the isotopic compositions of NBS 19 and L-SVEC standards.
• The prepared solutions were easy to handle and compatible with standard isotope analysis systems.

Conclusions:

• The blending method provides an accessible way to generate high-quality, inexpensive stable isotope reference materials.
• This approach facilitates routine two-point calibration for isotopic composition, enhancing laboratory quality assurance.
• The method is broadly applicable for creating isotope standards for diverse elements and compounds.