"HPLC"s are not calibrated. They are Qualified. This is a common error in terminology. They are complex instruments which consist of many modules or components, not a single component.

What is your actual question? DO you wish to develop an HPLC method to detect and measure xylan (or xylan hydrolyzate) in a sample? If you wish to measure the amount found, then after developing the method you would construct a proper calibration table consisting of several standards which bracket the actual sample and use the calibration table to interpolate the value found. IF THIS IS WANT YOU ARE LOOKING FOR: Try a simple keyword search on the web for HPLC , XYLAN, METHOD to look at examples. You will find papers, application notes are articles to review.

Which xylan? The polysaccharide or the fluoropolymer coating?

Which chromatography? I've heard the term "calibrate" applied to markers with known molecular weight for size exclusion chromatography.

Thank u for all your answers and the corrections. Yes i try to analyze Xylan (beechwood) and it's hydrolyzates. I tried to bulid an calibration tabel before but it didnt worked for some reassons. Thank u for the link.

The below mentioned researcher has many articles on hemicelluloses (including xylan). Happy new year.

https://www.researchgate.net/profile/Yehia_Fahmy