My experience with comparable systems that are already commercially  
available (the Los Gatos water isotope instrument) is that they are  
very convenient, just past the threshold of acceptable in terms of  
precision and reliability of standardization schemes, but the  
practical sample-size requirements are actually quite large and  
performance drops of precipitously with decreasing sample size.  As a  
result, they are wonderful ways of quickly and easily generating  
garden-variety water-isotope data, but seem very unlikely to ever  
provide the highest quality C or O isotope data or to become a  
preferred approach for compound-specific measurements on materials  
that are sample-limited.


On Jan 28, 2009, at 8:40 AM, Robert Panetta wrote:

> Hi All,
> I just came back from a demonstration of Picarro's Wavelength- 
> scanned cavity ring down spectroscopy at ASLO and saw there have a  
> been a few excellent demonstrations of its use for stable isotope  
> analysis (deuterium, oxygen, and carbon). It looks incredible and I  
> think may even have potential to eventually replace our (mostly)  
> beloved IRMS instruments. But before I go too far, does anyone have  
> experience with this system for isotope analysis? Has anyone coupled  
> it to a periphery (e.g., elemental analyzer)? Have I really been  
> given a glimpse into the future or am I being deluded by a savy  
> sales campaign?
> Thanks!
>
> -- 
> Robert J. Panetta