Hi,

I have been analyzing the concentration of glucose and xylose in complex media which had overlay added to trap fermentation product. I noticed variable glucose and xylose results from my sugar data. I have checked the peak symmetry, used qc standards, retention time, area and everything looks good. That leaves me with the sample preparation method and possible interference from the overlay which in this case is durasyn. I would like to know if anyone has used overlay in their fermentation and how that has impacted sugar readings analyzed using HPLC. Thanks.