The column name corresponds to ph value of the mobile phase where acid residue on the column switches from ionize form to neutral one.

Transcription

1 Novel stationary phases Cation Exchange Retention of polar compounds without ionpairing reagent Direct Plasma Analysis Unique adjustable selectivity Versatility Separation of organic and inorganic compounds LC-MS, ELSD, preparative chromatography New alternative to ion chromatography SIELC Technologies provides several different columns with negatively charged functional groups due to the embedded anionic ion-paring reagent. Primesep A is the strongest acidic column, while Primesep 300 is the weakest acidic column. The Primesep 100 and Primesep 200 columns are in between. Difference in the functional group acidity allows selecting the most appropriate column for a particular set of basic compounds that differ in their pka value. The embedded acidic functional group can be in an ionized form, or in a non-ionized form, depending on the ph of the mobile phase. In order to get retention by ion-exchange mechanism on Primesep columns, the ph of the mobile phase should be selected close to, or above, the transition value of embedded acidic groups. Below the transition ph value, the column behaves as a regular reverse-phase column with an embedded non-ionized polar group. The column name corresponds to ph value of the mobile phase where acid residue on the column switches from ionize form to neutral one. Cation-exchange Column Type About 50% of embedded acidic groups ionized at transition ph value Separates basic compounds Primesep 300 ph = 3 strong bases, dibases Primesep 200 ph = 2 strong bases, dibases Primesep 100 ph = 1 weak, medium bases, AA, metals Primesep A ionized in all working ph weak bases, AA, metals Switch Phase SIELC Technologies. Copyright SIELC Technologies /23/2004

2 Benzene Ring Compounds Reverse Mode vs. Normal Mode. Aromatic Compound Separation Primesep mixed-mode stationary phases provide two functional groups for interaction with analytes. One is a very hydrophobic alkyl chain; another is a very hydrophilic acid residue. With two functional groups of such difference in polarity, multiple separation modes can be performed on a single column. Neutral compounds can be resolved in reverse, normal, or polar organic mode. Charged molecules can be resolved in reverse, normal, polar organic, ion-exchange, or ionexclusion modes. The combination of more than one mode is typical for ionizable molecules. Selection of the mode of separation is governed by type of the mobile phase selected for the particular separation. Different modes of separation offer different selectivity and often reverse elution order of the peaks, which may be important for quantitation and preparative separation. SIELC Technologies. Copyright SIELC Technologies

3 Ethanolamines Po lar compounds are separated by degree of polar interaction that is adjustable by amount of water in the mobile phase Hydrophobic and Hydrophilic Compounds C omplex mixture of polar and very ve ry hydrophobic compounds

4 Steroids Separation in Reverse and Normal Mode Amino Sugars Analysis in Ion Exchange and Reversed mode N eutral non polar compounds elute proportional with decreased organic concentration Po lar compounds show a different response allowing selectivity changes

5 Catecholamines Separation Se parate broad range of analytes on one phase using simple mobile phases that are co mpatible with mass spec detectors Ion-exclusion and reversed phase for DIACIDS Copyright SIELC Technologies El ution time and order can be adjusted by organic, water and acid levels elution

6 Compound: Nucleic Bases Nucleic Bases Separation Po lar organic compounds retain poorly on RP columns, The ionizble group on a molecule is retained on the cation embedde pri mesep 200 phase Nucleosides Deoxyribo Nucleic Acid Separation

7 Simple Amines and Ammonia Separation Separation of Amines Neutral, Base, and Acid on Primesep A Column