Assay of D3 as per British pharmacopeia

[ubhanu.pharma]

Hi,
I have a problem in assay of Vitamin D3 in Normal phase with Pentenol and Hexan as Mobile phase, i need to know the Retention Time of Cis and trans for system suitability can any one help me

[prepcolumn]

1) Open the link below
2) Write Colecalciferol
3) Click chromatogram: available
4) You will see all peaks including trans impurity (vit D3: around 20 mins, trans isomer: around 11.5 mins)

https://extranet.edqm.eu/page7/page2/page2.html