As after thought the above Invitrogen kit is designed for detecting
chitinase activity in histological samples. I did a quick pubmed search
and there is a recent review:
An improved method for detection and quantification of chitinase
Can J Microbiol. 2005 Jun;51(6):491-5.
Although it looks from the abstract that they also use image analysis
as a quantification method which could be used in the Invitrogen kit
above. If you obtain the paper can you forward me a copy.