Multiproduct facility

We manufacture multiple type solutions for injection in our facility and we assess our cleaning procedures by determining the hardest to clean active (least soluble) within each group of products using the same cleaning procedure. We attempt to prove that we can clean products to the level required for the most porent product within that cleaning group.

We also make partenteral products containing vitamins within the facility. I have determined that we would have to have an analytical method which would have a LOD or 0.00005mg/ml, which we can not achieve by HPLC.

Is there any special considerations for vitamins for cleaning validation?