I have a problem with my Initial Calibration Verification with 2,4,5-T and I was wondering if there is a problem during the prep process for this compound to continuously have a low %difference on my ICV. Throughout my Calibration of 7 levels my % difference between the nominal amount and calculated amount remains between +/- 20%. When i run my ICV the %D is usually -16% or -20%. Both the intermediates for the 7 levels of calibration and ICV are methylated in the same manner. How can i fix this problem so that i can increase the amount of 2,4,5-T in my ICV so the %D is inside the QC limits? If you need more information about this please do not hesitate to ask. Could it be the ICV Stock solution? I also bottle everything in amber vials jsut in case there is any light sensitivity with this compound. Also the Internal standards for each of the ICV's are at normal range.