Stable Isotope Laboratory

The Stable Isotope Laboratory is run as part of the Farquhar Laboratory, but also provides services to the rest of RSB, ANU and outside researchers. We aim to give precise and timely isotopic and elemental analyses at a reasonable price. The lab concentrates on hydrogen, carbon, nitrogen and oxygen isotope analyses. The majority of our work is performed on conventional mass spectrometers but increasingly laser techniques form a valuable part of our repertoire: nearly all water analyses are performed by a cavity ring-down laser and we are installing a Los Gatos Research analyser to examine the δ13C and δ18O of CO2. We also recently installed instruments to support compound-specific analyses using either LC and wet oxidation (for δ13C only) or GC combustion/pyrolysis for H, C, N or O isotopic analysis. We are not offering compound-specific analyses as a commercial operation but are happy to receive collaborative proposals.


As we are a research laboratory, the selection of equipment available (and how it is connected) is somewhat fluid but the following gives a typical overview. Note that δ13C and δ15N analyses plus %N, on organic solids, are almost always available. See the slideshow below for details of equipment set-up and photographs.

  • Two Micromass Isochrom CF-IRMS machines
  • Two Isoprimes, one with a micro-volume dual-inlet
  • Laser CO2 analyser 1102i Cavity Ring-Down Spectrometer
  • Los Gatos Research 46-R CO2 analyser

Examples of past projects

  • The bulk of our analyses are δ13C of plant material. Typically we examine 1 to 2 mg of dried and ground leaf. The analyses are widely used for determination of relative Water Use Efficiency (WUE) and for other examinations of plants’ interaction with their environment. Tens of thousands of analyses have been performed in this laboratory that have contributed to the breeding of improved strains of wheat, sorghum and canola etc. The head of the laboratory, Professor Graham Farquhar, has received numerous awards for his work in this area.
  • Oxygen isotopes of both dry matter and leaf water have been examined extensively, providing information both on how water moves through leaves and how leaves interact with the atmosphere around them.
  • Hydrogen isotopes from water and lipids give a different view of water movement and atmospheric interaction.  Hydrogen in lipids gives a long record of past water and environmental conditions.
  • Nitrogen isotopes have been examined in numerous plants, primarily to look at fertiliser uptake.
  • But we don’t just analyse plants!  Recent projects have includes the carbon and nitrogen isotopic analysis of ants, sea-lion whisker, bird feathers, sewage and eel grass. Normally we work at natural abundances but are also willing to take on enriched materials. We have analysed water from all over Australia, including from underground.

Analysis Services

Costs of analysis

The amount that we charge for our work depends largely on how many samples are in the contract, urgency of turnaround, difficulty of processing, and collaboration, if any. Lower rates may be offered to students and for small exploratory projects intended to support larger grant applications.

Stable Isotope Lab analysis price list
Material Analytical process Price (AUD inc. GST)
Plant Grinding 3.00
Plant Weighing 2.00
δ13C organic EA (Dumas)     17.00
δ13C & δ N15 organic EA (Dumas)     23.00
C&N isotopes + N%-C% EA (Dumas)     30.00
δ2H (δD) & δ18O water Picarro laser 20.00
δ18O organic Pyrolysis          30.00
δ2H (δD) organic Reduction on chromium 25.00

Shipping samples

Samples should be sent to

Stable Isotope Laboratory
Research School of Biology
R.N. Robertson Building (46)
The Australian National University
Canberra, ACT 0200

Updated:  13 June 2019/Responsible Officer:  Web Services/Page Contact:  Web Services