Hitachi CHROMASTER 5160 Instruction Manual page 678

3.6 Before Performing Analysis
NOTICE: 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.
Acetonitrile (special grade)
Acetonitrile (for HPLC)
Fig. 3-1 Absorption Spectra of Organic Solvents
3 - 28
Condition
Photometer: U-3000
Slit : 2 nm
Blank : Air