Waters CORTECS 1.6 um Columns - Manual (Page 5)

5
CORTECS Columns
A listing of commonly used buffers and additives is given in Table 2. Additionally, the column lifetime will vary
depending upon the operating temperature, the type and concentration of buffer used.
Note: Working at the extremes of pH, temperature and/or pressure will result in shorter column lifetimes.
table 3: CoRteCs Chemistry Characteristics
c. solvents
To maintain maximum column performance, use high quality chromatography grade solvents. Filter all
aqueous buffers prior to use through a 0.2 µm filter. Solvents containing suspended particulate materials
will generally clog the outside surface of the inlet distribution frit of the column. This will result in higher
operating pressure and poorer performance. See Section V for more information.
d. Pressure
CORTECS Columns can tolerate operating pressures up to 18000 psi (1241 bar or 124 MPa).
Note: Working at the extremes of pressure, pH and/or temperature will result in shorter column lifetimes.
e. temperature
Temperatures between 20–45 °C are recommended for operating CORTECS Columns in order to enhance
selectivity, lower solvent viscosity and increase mass transfer rates. When operating at high pH, lower operating
temperatures are recommended for longer column lifetime. Working at high temperatures (e.g. > 40 ˚C) may also
result in shorter column lifetimes.
Note: Working at the extremes of temperature, pressure and/or pH will result in shorter column lifetimes.
C
18
C
18
+ HIlIC
Chemistry
Intended use
General purpose, high-efficiency,
reversed-phase column. Balanced
retention of acids, bases and
neutrals at low and mid-range pH.
General purpose, high-efficiency,
reversed-phase column. A positively
charged surface delivers excellent
peak shape for basic compounds
at low pH.
High-efficiency column designed
for retention of extremely polar
analytes. Offers orthogonal
selectivity vs. C
18
columns.
ligand type Trifunctional C
18
Trifunctional C
18
None
Surface Charge modification None + None
endcap Style Proprietary Proprietary None
Carbon load 6.6% 5.7% Unbonded
ligand density 2.7 µmol/m 2 2.4 µmol/m 2 N/A
pH range 2-8 2-8 1-5
temperature limits 1
Low pH = 45 °C
High pH = 45 °C Low pH = 45 °C
High pH = 45 °C Low pH = 45 °C
High pH = 45 °C
O Si
O
O
O Si
O
O