pic reagent

[olivia]

Hi can anyone tell me what PIC reagent is and what the initials stand for.
Many thanks Liv

[Uwe Neue]

Paired Ion Chromatography. PIC reagents can be purchased from Waters.

[Consumer Products Guy]

Olivia - Paired Ion Chromatography is Waters' tradename, this technique is also called Ion Pair Chromatography. So you can purchase reagents from either Waters or elsewhere.

[olivia]

Many thanks
Liv

[Rafael Chust]

PIC or IPC reagents are phase modifiers, usually sodium salts of carboxilic acids. It is a technique used to "deionize" polar compounds - such as amines - and increase their retention in reversed phase chromatography.

[zokitano]

PIC or IPC reagents are phase modifiers, usually sodium salts of carboxilic acids. It is a technique used to "deionize" polar compounds - such as amines - and increase their retention in reversed phase chromatography.

You mean I suppose: sodium salts of alkyl sulfonic acids?

Regards

[Rafael Chust]

Exactly! Sorry fo mispelling but my "basic chemistry english" is a bit rusty!

[Bruce Hamilton]

I'm probably being picky, but...

I believe PIC As are tetrabutylammonium hydrogen sulphate ( low UV ), or tetrabutyl ammonium phosphate ( standard form ), and the PIC B5-B8 are the alkane sulphonic acids. Not sure of difference between Low UV and standard form for PIC Bs.

I'm not sure they are just the sodium salts, because I once used a PIC reagent and the equivalent sodium salt from a different supplier, and the retention was different. I didn't investigate further.

Bruce Hamilton

[Rafael Chust]

Bruce:

You are absolutely correct. I used this stuff when I worked for Waters in mid-80s and didn't research before posting.

In fact PIC A - for acids - is an tetrabutylammonium salt and PC B's - for bases - are alkane (B5-penta to B8-octa) sulphonic acids.

Of course Waters use quite pure preparations at adequate concentrations, but you must obtain the same results using the same compunds from any other source.

I had customers that used PIC reagents and them moved to do their own with same success. Anyway, due to new chemistries in RPLC, PIC is becoming less and less popular.