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).
Organic and inorganic acids and ions can be separated on a Primesep B4 column based on their ionic properties. Method can be used for quantitation of residual acids in various products and sample matrices. Trifluoracetic, hydrochloric, methanesulfonic, and nitric acids are separated using ACN-water-ammonium formate. Ions can be detected by ELSD, CAD or LC/MS.
TFA (Trifluoroacetic Acid)
Ion chromatography is usually used for analysis of hydrophilic organic and inorganic ions. Same separation can be achieved on HILIC/mixed-mode Obelisc N HPLC columns. Obelisc N HPLC columns have very polar groups on their surface: one of the groups is basic and the other acidic. In case of low organic concentration, two groups are connected by hydrophilic linker. Obelisc N column can be used as cation-exchange and anion-exchange column. This allows to separate positively and negatively charged molecules in one run. Five anions (chloride, bromide, methanesulfonate, nitrate and perchlorate) along with one cation (sodium) were separated in one run. Method is compatible with ELSD, CAD and LC/MS and can be used for analysis of various hydrophilic and hydrophobic cations and anions in one HPLC run.