June 11, 2015, 715004754 Rev. A
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1.2.3.2 Inhomogeneities in solution
The differential refractometer measures the difference in refraction between the
reference solvent and the sample solution. Most common inhomogeneity problems
are due to improper solvent preparation.
• The mobile phase must be of constant composition.
• Gradient separations are not recommended since the Δn from the mobile phase
change is larger than that from the analyte peak.
Because the 2414 RI detector is sensitive to contaminants, replacing tubing can often
require long wash times. See Chapter 4 for more information.
1.3 Detector description
The detector is designed for high-performance liquid chromatography applications. It
can operate as a standalone unit with an integrator or with a Waters system controller
or Waters data system.
Refer to Appendix B for system specifications, and to Chapter 4 for solvent
considerations.
Figure 1–5: 2414 RI detector
1.3.1 Range and attenuation
The detector functions with solvents with refractive indices between 1.00 and 1.75.
The measurement range of the instrument is 7 × 10
–9
to 5 × 10
–4
refractive index units
full scale (RIU-FS mode).
1.3.2 Features
The detector has these key features:
• Standalone programmability – Stores up to 10 user-defined programs (or
methods) consisting of up to 16, programmable, timed events and 1 threshold
event (in standalone RIU mode).