If you are looking for optimized HPLC method to analyze Trimethylsulfonium check our HPLC Applications library

For optimal results in HPLC analysis, it is recommended to measure absorbance at a wavelength that matches the absorption maximum of the compound(s) being analyzed. The UV spectrum shown can assist in selecting an appropriate wavelength for your analysis. Please note that certain mobile phases and buffers may block wavelengths below 230 nm, rendering absorbance measurement at these wavelengths ineffective. If detection below 230 nm is required, it is recommended to use acetonitrile and water as low UV-transparent mobile phases, with phosphoric acid and its salts, sulfuric acid, and TFA as buffers.
For some compounds, the UV-Vis Spectrum is affected by the pH of the mobile phase. The spectra presented here are measured with an acidic mobile phase that has a pH of 3 or lower.

The separation of steroids on Primesep 100 demonstrates the versatility of Primesep columns in both polar organic and ion-exchange modes in the separation of sulfonium ions. The high organic mobile phase retains methane sulfonic acid by a polar organic mechanism and separates methoxydimethylsulphonium and trimethylsulfphonium cations by polar organic and cation exchange modes. The separation method uses a mobile phase mixture of water, acetonitrile (MeCN, ACN), and trifluoroacetic acid (TFA) with evaporative light scattering detection (ELSD).