I seems to get an insoluble product forming with that mobile phase for C18 : column pressure increase, and check valve eventually get stuck. Did anybody bump in the same problem .. and found a solution. Thanks
MB are filtered , and consist of A 6mM Tetrabuthylamonium HSO3 pH 7 ( with NH4OH)and B MeoH , gradient , Column is Xbridge C18 , so far after like 50 injection they clog (sofare 6 of them) , simultaneously we observe problem with check valve .
Try mixing equal volumes of Mobile Phase B with A. Does TBAH precipitate? I would think yes since it is not soluble in 100% MeOH. Therefore, use 95% MeOH with 5% Water (pH 7). Always use a 'small' amount of water in your mobile phases.