Ascentis® Express AQ-C18 UHPLC Columns

Resistant to de-wetting; compatible to 100% aqueous mobile phase

Ascentis® Express 90 Å AQ-C18, based on Fused-Core® particles is a C18 bonded phase prepared using a proprietary procedure that incorporates a small amount of polar silane which makes the phase resistant to de-wetting. This resistance to de-wetting allows the users of the AQ-C18 phase to run highly-aqueous (up to 100%) mobile phases. The modified C18 phase exhibits enhanced retention of polar compounds under 100% aqueous conditions. Ascentis® Express 90 Å AQ-C18 is a reversed-phase packing that can be used for basic, acidic, and neutral compounds.

Ascentis® Express AQ-C18 Specifications
Silica: Type B (High purity silica)
Particle Platform: Superficially porous particles (SPP)
Phase Chemistry: Polar modified Octadecyl
Particle Size: 2.0 µm / 2.7 µm / 5.0 µm
Pore Size: 90 Å
Carbon Load: 6.5% / 6.7% / 5.6%
Surface Area: 135 m²/g
pH Range: 2 - 9
Max Temperature at Low pH: 60 °C
Max Temperature at High pH: 40 °C
Endcapped: Yes

 

Ascentis® Express 90 Å AQ-C18 is a high-speed, high-performance liquid chromatography column based on a superficially porous Fused-Core® particle design. The Fused-Core® particle provides a thin porous shell of high-purity silica surrounding a solid silica core. This particle design exhibits very high column efficiency due to the shallow diffusion paths. Three different particle sizes are available for your specific needs:

Fused-Core® particle size 2 µm

Fused-Core® particle size 2.7 µm

Fused-Core® particle size 5 µm

Figure 1. Ascentis® Express UHPLC and HPLC columns

Stability test under 100% aqueous conditions

The separation example demonstrates the stability under 100% aqueous conditions of Ascentis® Express 90 Å AQ-C18 in contrast to a common C18 phase. After the pump was stopped and restarted, the retention and resolution were maintained with the Ascentis® Express 90 Å AQ-C18, where the C18 phase showed a dramatic change in selectivity.

The separation example on top demonstrates the stability under 100% aqueous conditions of Ascentis® Express 90 Å AQ-C18 in contrast to a common C18 phase. After the pump was stopped and restarted, the retention and resolution were maintained with the Ascentis® Express 90 Å AQ-C18, where the C18 phase showed a dramatic change in selectivity.

 
Stability Test under 100% Aqueous Conditions
  1. Thiourea
  2. 5-Fluorocytosine
  3. Adenine
  4. Thymine
 

Figure 2. Stability test under 100% aqueous conditions

 

Columns Ascentis® Express 90 Å AQ-C18, 5 cm x 4.6 mm I.D., 2.7 μm
Ascentis® Express 90 Å C18, 5 cm x 4.6 mm I.D., 2.7 μm
Isocratic: Water/0.1% TFA
Temperature: 30 °C
Injection Volume: 0.5 μL
Detection: UV 254 nm, PDA

 

Materials

  Column dimension Paricle Size
  Column
length (cm)
  Column ID (mm) 2 µm 2.7 µm 5 µm
HPLC /UHPLC Columns            
Ascentis® Express 90A AQ-C18 2 X 2.1 on demand 577320-U on demand
Ascentis® Express 90A AQ-C18 3 X 2.1 on demand 577321-U on demand
Ascentis® Express 90A AQ-C18 5 X 2.1 565349-U 577322-U 581363-U
Ascentis® Express 90A AQ-C18 7.5 X 2.1 on demand 577323-U on demand
Ascentis® Express 90A AQ-C18 10 X 2.1 565351-U 577324-U 582702-U
Ascentis® Express 90A AQ-C18 15 X 2.1 565362-U 577325-U 584572-U
Ascentis® Express 90A AQ-C18 25 X 2.1 565363-U on demand 584573-U 
Ascentis® Express 90A AQ-C18 2 X 3.0 on demand 577326-U on demand
Ascentis® Express 90A AQ-C18 3 X 3.0 565364-U 577327-U 584574-U
Ascentis® Express 90A AQ-C18 5 X 3.0 565365-U 577328-U 584575-U
Ascentis® Express 90A AQ-C18 7.5 X 3.0 on demand 577329-U on demand
Ascentis® Express 90A AQ-C18 10 X 3.0 on demand 577330-U 584576-U
Ascentis® Express 90A AQ-C18 15 X 3.0 577160-U 577331-U 584577-U
Ascentis® Express 90A AQ-C18 25 X 3.0   on demand on demand
Ascentis® Express 90A AQ-C18 2 X 4.6   577332-U on demand
Ascentis® Express 90A AQ-C18 3 X 4.6   577333-U 584578-U
Ascentis® Express 90A AQ-C18 5 X 4.6   577334-U 584579-U
Ascentis® Express 90A AQ-C18 7.5 X 4.6   577335-U on demand
Ascentis® Express 90A AQ-C18 10 X 4.6   577336-U 584580-U
Ascentis® Express 90A AQ-C18 15 X 4.6   577337-U 584581-U
Ascentis® Express 90A AQ-C18 25 X 4.6   on demand on demand
Guard columns            
Ascentis® Express 90A AQ-C18 Guard, 3 ea 0.5   2.1 577161-U 577338-U 584582-U
Ascentis® Express 90A AQ-C18 Guard, 3 ea 0.5   3.0 577162-U 577339-U 584583-U
Ascentis® Express 90A AQ-C18 Guard, 3 ea 0.5   4.6   577340-U 584584-U