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| NUCLEOSHELL® core-shell silica phases for HPLC |
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| Features |
NUCLEOSHELL® |
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Core-shell technology:
 Solid core of silicon dioxide,
homogeneous shell of porous silica Highest efficiency compared to traditional totally porous materials Pore size 90 Å; particle size 2.7 µm (core 1.7 µm); specific surface 130 m 2/g Lower back pressure also allows use on conventional LC systems
Pressure stability up to 600 bar |
NUCLEODUR® |
Summary of available NUCLEOSHELL® phases
| Phase |
Modification |
% C |
pH range |
Particle size [µm] |
USP |
Structure |
| RP 18 |
Octadecyl, multi-endcapping |
7.5 |
1–11 |
2.7 |
L1 |
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| Phenyl-Hexyl |
Phenyl-Hexyl, multi-endcapping |
4.5 |
1-10 |
2,7 |
L11 |
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| PFP |
Pentafluorophenyl, multi-endcapping |
~ 3 |
1–9 |
2.7 |
L43 |
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| HILIC |
Ammonium – sulfonic acid |
1.3 |
2–8.5 |
2.7 |
– |
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| Demands on HPLC separations are constantly increasing with respect to separation efficiency and detection limits as well as concerning the time requirements for each analysis. Core-shell technology sets new standards for increasing efficiency in research and quality control. |
| Benefits of core-shell technology |
Core-shell particles vs.
totally porous silica gel |
| Short diffusion paths |
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Rapid mass transfer (C term of the Van Deemter equation) |
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High flow velocity without peak broadening for fast LC |
| Narrow particle size distribution (d90/d10 ~ 1.1) |
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Stable packing |
| High heat transfer |
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Minimized influence of frictional heat |
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Column efficiency of NUCLEOSHELL® ~ 250000/m (HETP ~ 4 µm) |
| Resolution Rs as function of particle size |
| Columns: |
50 x 4 mm
NUCLEOSHELL® RP 18, 2.7 µm
NUCLEODUR® C18 Gravity, 3 µm
NUCLEODUR® C18 Gravity, 1.8 µm |
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Eluent:
Flow rate:
Temperature:
Detection: |
acetonitrile – water (60:40, v/v)
1 mL/min
25 °C
UV, 254 nm |
Peaks:
1. Naphthalene
2. Ethylbenzene |
Better resolution at
lower back pressure and
shorter retention time |
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