History of the Lab

Dr. Brian Fry established the MBL Stable Isotope Laboratory at The Ecosystems Center in 1985. The first Isotope Ratio Mass Spectrometer (IRMS), a dual-inlet Finnigan MAT 251, was purchased with a NSF grant and matching funds from the A. W. Mellon Foundation. With the help of Bob Michener, the lab quickly started producing high quality δ¹⁵N, δ¹³C and δ³⁴S data on ecological sample materials.

In 1989, Hap Garritt and Kris Tholke assisted Brian in setting up one of the first automated IRMS systems with the newly acquired Finnigan Mat Delta S dual-inlet mass spectrometer and its innovative "trapping box" (a combustion & cryogenic gas purification unit) purchased with a grant from NSF.  This system, for the first time, allowed the simultaneous analysis of δ¹⁵N and δ¹³C on individual sample aliquots (Fry et al., Analytical Chemistry 64, 1992.)

Tholke assumed management of the lab in 1994 and, in 1997, she set up the Europa 20-20 continuous flow-IRMS system that was purchased with a NSF grant studying nitrate uptake and retention in streams.  This continuous-flow system, which greatly increased sample throughput, was initially dedicated to δ¹⁵N tracer study samples.

In 2000, Marshall Otter was hired to manage the laboratory.  With the trapping box on its last legs, the Europa 20-20 became the workhorse system for doing δ¹⁵N, δ¹³C, and δ³⁴S analyses.  In 2001, the stable isotope lab was moved to the new C.V. Starr building on the MBL campus which also houses the offices and general use labs of The Ecosystems Center.

In 2005, the Delta S was sold to make room for two new GV Instruments Isoprime continuous flow-IRMS systems and five automated sample preparation units that were purchased with funds from a NSF grant awarded to Paul Steudler.  The new systems have greatly expanded the lab's capabilities, allowing for the analysis of δ¹⁵N, δ¹³C, δ¹⁸O and δ²H on a larger variety of ecological samples, including water, trace gases, and specific compounds in organic materials.