analysis of alkylnaphtalene sulfonic acids derivatives

[Eric]

I am looking for an HPLC method for the analysis of alkylnaphtalene disulfonic and monosulfonic acid derivatives.

Thanks in advance.

[XL]

Eric,

I worked with alkylnaphtalene sulfonates, as well as other various surfactant analysis.

To answer your question, you can use ACN/50 mM ammonium acetate mobile phase system. Whithout knowing what alkyl groups are, I assume some compounds of interest, say di-sulfonates, are very hydrophilic. Therefore, you can use a reversed-phase that is compatible with highly aqueous mobile phase, and a gradient method from 10% to 80% ACN in 30 min. This way you can see different cluster (isomers) elute out at various time. Then, if necessary, you can develop an isocratic test based on the result from your gradient screening method.

Here are other things that I think should be useful:
Column size: 5um, 4.6x150
Flow rate: 1 mL/min
Detection: UV @ 225 nm

If you are extensively working with surfactant analysis, you are welcom to contact me for details.

Good luck.

X.L.