Hi, I need advice regarding this matter.
There's a biopesticide called Vectobac WP. It contains Bacillus thuringiensis spore as the active ingredients. From my understanding it forms crystal protein which can be digested to release endotoxin to kill mosquito larvae. It is in powder form and need to be mixed with water at x mg/L before application. The mixture will be dark brown in colour. A client tasked us to check whether their contractor mix the product according to the label rate which is x mg/L. They'll regularly sample their contractor's preparation and send for test. But no one in the lab knows how to do it...
I have an idea but not sure whether it works.
First is to mix the product according to the label rate and conduct spectro to get the reading. Do it for a few reps.
Then whenever samples are received, we will just do spectro to get the reading and use maybe Chi square test to see whether the reading is significantly different from the standard. Would this work? The mixture is dark brown in colour, will it affect the reading/which wavelength is better?
I was told that I'll need technical grade of the active ingredient to construct a standard curve. However, because I don't need the exact concentration of the sample, I figure that it is not required. Even if standard curve is required, can I use the product with maybe 35% concentration of the ai instead of the technical grade?
I look forward for your kind feedback.
P/S: we dont have a spectrophotometer in the lab ... that's why I need to need some input before I can ask to buy 1.