I have been trying to make a dissolved oxygen sensor, the basics are described on this page.
I have a good understanding of the electronics behind this measurement, but I cannot find a suitable oxygen sensitive dye to use. I have read quite a bit about room temperature phosphorescence, and thought that erythrosin b might but a suitable candidate, it has an excitation wavelength of 525 nm, and radiates in near-IR. After more reading, I found that it needs to be in a sol-gel or similiar substrate. All of the reading I've done seems to require some sort of substrate and this isn't what commercial dissolved oxygen sensors are using. They appear as just a thin, hard disc. Additionally, I don't have any equipment or experience with sol-gels.
I'm looking for any information on what chemical and process commercial systems are using. Or, a simple way to get erythrosin b to work. My tests with it so far have not shown any phosphorescence at all.
Thanks for your time.