Hitachi CHROMASTER 5160, Instruction Manual

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NOTE : For Using Organic Solvents as Mobile Phase
1. When using organic solvents, be careful about UV
cut off wavelength.
UV cut off wavelength:
Light cannot be transmitted in the range shorter
than this wavelength.
For example:
Cut off wavelength of chloroform is 245 nm.
Chloroform cannot be used in the range shorter than
245 nm (e.g. 210 nm).
2. Boiling point of mobile phase
Solvents of low boiling point cannot be used as
mobile phase. Use solvents whose boiling point
is 55

C or higher.
Solvents of low boiling point are not only
dangerous but also generate bubbles when sucked
by pump so that normal pumping will be impossible.
3. When performing high sensitivity analysis with UV
detector, use solvents which absorb especially
small amount of UV light.
Since special grade reagents such as methanol
and acetonitrile generally used absorb the shorter
wavelengths a lot, use reagents for liquid
chromatograph commercially available.
Fig. 3-7 Absorption Spectra of Organic Solvents
Condition
Photometer : U-3000
Slit
: 2 nm
Blank : Air
Acetonitrile (special grade)
Acetonitrile (for HPLC)
Abs
1.000
0.900
0.800
0.700
0.600
0.500
0.400
0.300
0.200
0.100
0.000
200.00 250.00 300.00 350.00 400.00
190.00 450.00
nm