HPLC grade water in Preparative LCMS

Hello Yuhang ,

I've moved this to the LC/MS Forum for better visibility.

Hi Yuhang ,

I am not a preparative LCMS user, but as a conventional LCMS user my rule of thumb is to use exclusively LCMS grade reagents and solvents whenever possible. Depending on the application, cost and space may affect whether purchasing LCMS grade water is feasible. Based on the limited number of applications that I have run, I think that ASTM Type I water from an in-house water polisher may be a suitable alternative. For an additional level of insurance, some brands of water polishers have filtration cartridges specific to the application.

we use 18.2 Mega Ohm water straight from the purifier (ELGA) and add LCMS grade additives to buffer, we use HOOCH and ammonium formate, never any problems with my 6495TQ.