Chromatography Forum

Could anyone please give me any addresses to purchase (primary) reference standard of non-pharmacopoeial substance? Thank you for the information.

Best regards,
Siswanto Tanuatmojo

Check www.lgcpromochem.com

Dr. Muller, thank you for the link. But I still could not find the reference standards for risedronate sodium and valacyclovir HCl.

I think you should ask the suggested supplier, as both compounds are commercially supplied by major pharmaceutical companies ( Adventis and GlaxoSmithKline respectively ). The suggested supplier may be able to obtain reference standards from those companies.

Large pharma companies usually provide reference standards for clinical researchers, subject to certain conditions. If you are a generic manufacturer, it's highly unlikely they will supply, and you may have to establish your own reference from one of the many suppliers of the compounds listed at www.chemexper.com.

Bruce Hamilton

Dear mr syx,

Actually we do not have Valacyclovir and risedronate product, but for others product we used to ask to the supplier wether they have the refference substance or not before purchasing the materials.

Valacyclovir HCl is an alkaloid salts, why don't you develop the method of analysis by Titrimetry in non aqueous solvents, so you do not require a reference substance?
For Risedronate sodium, i think it can be determined by acidi-alkalimetric Titration.

valacyclovir HCl is the hydrochloride salt of amino acid, L-valyl ester of the antiviral drug acyclovir.

we supply valacyclovir HCl !

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