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Universal HPLC columns?

Primesep 100 and Obelisc R / N - probably the most universal columns ever made

SIELC Technologies manufacture the Primesep HPLC columns, specifically designed for mixed-mode separations. Primesep columns are capable of separating a tremendous range of compounds by different separation modes based only upon mobile phase selection. These columns were designed with the understanding that proper inclusion, not elimination, of secondary interaction is a powerful tool in selectivity control, column stability, and separation reproducibility.

The Obelisc columns are the first commercially available columns with Liquid Separation Cell technology. Obelisc R, with reversed-phase characteristics, and Obelisc N, with normal-phase characteristics, separate polar and non-polar compounds using multiple separation mechanisms. This duo replaces multiple HPLC columns such as reversed-phase (RP), AQ-type reversed-phase, polar-embedded group RP columns, normal-phase, cation-exchange, anion-exchange, ion-exclusion, and HILIC (Hydrophilic Interaction Liquid Chromatography) columns. Method development is simplified by using only two Obelisc columns and a few simple mass spec or low UV (<220 nm) compatible mobile phases.

The separation of peptides and proteins by Promix columns is based on a combination of two interactions - hydrophobic and ionic. This is possible due to a new type of separation media - a chemical combination of hydrophobic and ionic functional groups on a ligand bonded to a silica support.

SHARC columns - they are the first commercially available columns with separation based primarily on hydrogen bonding.

 

Primesep columns

Acidic Primesep phases (mixed-mode cation exchange columns)
     with negatively charged functional groups
Analysis of ...
Primesep A (ionized in all working pH)
the strongest acidic phase		 weak bases, amino acids, metals
Primesep 100 (transition pH = 1) The most versatile column of the family
strong acidic phase		 weak / medium bases, amino acids, metals
Primesep P (transition pH = 1) Separates aromatics with pi-pi interaction
medium acidic phase		 weak / medium aromatic bases
Primesep 200 (transition pH = 2) Separates isomers and structurally-related compounds
weak acidic phase		 strong bases, dibases
Primesep 500 (transition pH = 5)
weakest acidic phase		 strong bases, dibases, polybases

In order to get retention by cation-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 and can be used in 100% aqueous mobile phase ("AQ" type column).

 

Basic Primesep phases (mixed-mode anion exchange columns)
     with positively charged functional groups
Analysis of ...
Primesep B (pH range 1.5 - 4)
strong basic phase		 acids, bases, neutrals (add trifluoroacetic, phosphoric, perchloric or formic acid to the mobile phase)
Primesep B2 (pH range 1.5 - 7)
weak basic phase		 acids, bases, neutrals (add ammonium acetate to the mobile phase)
Primesep B4 (pH range 2 - 4.5)
embedded basic ion-pairing groups		 acids, bases, neutrals, hydrophobic bases, surfactants
Primesep D (pH range 1.5 - 4)
designed for direct plasma injection		 hydrophobic, acidic components; proteins and peptides elute as a sharp peak in void or pre-void time
Primesep SB (pH range 1.5 - 5)
strong basic phase		 acids, bases, neutrals, Zwitterionics, natural product extracts
Primesep PB (pH range 2 - 5)
embedded aromatic and basic ion-pairing groups		 acids, aromatics, neutrals
Primesep AB (ionized in all working pH)
embedded acidic and basic ion-pairing groups		 strong acids and bases simultaneously

 

Other Primesep phases

 Analysis of ...
Primesep C (pH range 3 - 7) Unique elution order of positively charged molecules
embedded complex-forming groups		 amines, sulfonium, phosphonium and metal ions
Primesep P
embedded aromatic and acidic ion-pairing groups		 structural isomers of aromatics
Primesep S
normal-phase analytical column with embedded acidic ion-pairing groups		 Suitable for the separation of common sugars and other neutral, very polar molecules. Retains and separates amino acids with different buffers at low concentration. Separates weak bases by ion-exchange mechanism, acids by ion-exclusion mechanism.

 

 

Obelisc columns

Multiple separation mode (RP, NP, HILIC, IE)

 Analysis of ...
Obelisc N
anions on the surface, separated from cations by hydrophilic chain		 sugars, amino acids, carboxylic acids, aromatic acids
Obelisc R
cations on the surface, separated from anions by hydrophobic chain		 polar drugs, amino acids, PAHs

This duo replaces multiple HPLC columns such as reversed-phase (RP), AQ-type reversed-phase, polar-embedded group RP columns, normal-phase, cation-exchange, anion-exchange, ion-exclusion, and HILIC (Hydrophilic Interaction Liquid Chromatography) columns. Method development is simplified by using only two Obelisc columns and a few simple mobile phases.

 

Promix columns

Separation of peptides and proteins based on hydrophobic and ionic interactions

 Analysis of ...
Promix SP
100A pore size		 small peptides under 1 kDa with pI value below 6
Promix AP
100A and 300A pore sizes		 small and medium size peptides under 3 kDa with pI value below 7
Promix MP
300A and 800A pore sizes		 medium size proteins and peptides (1 - 10 kDa)



SHARC columns

 

 Analysis of ...
SHARC 1
SHARC columns operate in non-aqueous mobile phase with separation based primarily on hydrogen bonding.		 A mixture of acetonitrile (MeCN), a weak solvent, and  methanol (MeOH), a strong solvent, are used as the mobile phase. Pure MeCN  has very insignificant amount of hydrogen bonding with the SHARC stationary phase, while MeOH interacts strongly with SHARC stationary phase, which reduces the retention of analytes with electronegative atoms, such as oxygen, nitrogen, fluorine. By changing the ratio of MeCN/MeOH the optimum retention profile can be obtained for many types of molecules with high selectivity, peak shape, efficiency, and speed.

 

 

UHPLC Fittings

- Strong stainless steel thread allows many more use-cycles than a one-piece PEEK design
- Finger-tight installation. PEEK tip installs permanently and cannot be lost
- Pressure rating up to 14,000 psi (1000 bar)
- One-size-fits-most applications, including columns, valves, and instrument ports
- Break-resistant - metal fitting can bend: but it won't break, and thus it can be simply replaced with another fitting, saving the expensive column
- Improves heat transfer with the incoming capillary, when a column heater is used
- PEEK and metal-capillary compatible
- Special capillary tube gripping mechanism allows strong holding effect of the tube, even with very gentle tightening force

Picture (left side) - Fitting for quick-release applications (eg., column-to-instrument connections)

Picture (right side) - Fitting for semi-permanent applications (such as valve-to-instrument connections or pump-to-autosampler connections)

SIELC Newsletter 03/2010: SmartFittings for Smart LC Applications