What is an RI detector?
A refractive index (RI) detector, also called a differential refractometer, measures refractive index when light is passed through an analyte-containing cell as compared to a reference cell containing just solvent.
Why We Use RI detector in HPLC?
HPLC Instrumentation RI detectors monitor the difference in RI between the column eluent containing analyte and a reference stream containing mobile phase only. These detectors are the closest to universal detectors in HPLC because any solute can be detected as long as its RI is different from that of the mobile phase.
What is sensitivity in RI detector?
A refractive index detector is a universal detector since it monitors a bulk property of the solution. Unfortunately, RI detectors have a very low sensitivity (mg/L range) and are subject to several caveats: RI detectors are very sensitive to changes in temperature. Both the detector and column must be thermostatted.
What is the difference between UV detector and RI detector?
Refractive index (RI) detection is the standard approach for quantitatively detecting sugars via high-performance liquid chromatography (HPLC), while ultraviolet (UV) absorbance detection is the most commonly used detection method for general HPLC analysis.
How do you stabilize a RI detector?
Follow these thirteen points to optimize the performance of your refractive index detector.
- Position the solvent and waste reservoirs correctly.
- Do not over pressurize the flow cell.
- Use the correct solvents.
- Check for leaks.
- Verify frit, filter and fitting quality.
- Control the optical unit temperature.
How does thermal conductivity detector work?
TCD works by having two parallel tubes both containing gas and heating coils. The gases are examined by comparing the heat loss rate from the heating coils into the gas. Normally one tube holds a reference gas and the sample to be tested is passed through the other.
How do you calibrate a RI detector?
- Start Refractive Index Calibration. 1 From the user interface start the RID Calibration (see Figure 18).
- Figure 18. Start Refractive Index Calibration.
- Purging the Sample and Reference Cells. 1 The purge valve will automatically switch to the On position.
- Fill the Sample Cell with Calibration Solution.
How do I reduce the noise on my RI detector?