[ngvtuan]

I have sample Multivitamin Effervescent Tablet weigh=3g ( Riboflavin sodium phosphate 1.6mg, calcium Patothenate 6mg, Thiamin mononitrat 1.4mg, Pyridoxin HCl 2mg, Nicotinamid 18mg, Folic acid 0.2mg, DL-anpha tocopheryl acetat 10mg, retinyl palmitat 1500UI). Please help me how to analysis Assay all them by HPLC with detector UV/Visble.

[Arkcon]

Most vendors of HPLC columns will have an example of this type of separation, and what column they suggest is best for the application, along with procedure.  What you actually do will depend on your equipment, and your budget for new columns.  See what you can do, then maybe come back to us with some specific problems you may be having.

*[EDIT]*
I've read your attachment, sorry for the delay, but I don't download just anything I find lying on the web.  It contains a number of chromatographic methods for the components.  You can either follow those, or look to column vendors for easier methods.