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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.
Principle of RI detector
Light beams or rays that transmits a substance refract at the boundaries of different substances, such as gas or liquid phases. Refractive index detection is a detection method that applies the principle of light refraction.
RI detectors used
A differential refractometer (DRI), or refractive index detector (RI or RID) is a detector that measures the refractive index of an analyte relative to the solvent. They are often used as detectors for high-performance liquid chromatography and size exclusion chromatography.
RI detector used in HPLC
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.
difference between RI detector and UV 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.
RI Detector Sensitivity
RI detectors are very sensitive to changes in temperature. Both the detector and column must be thermostatted. The detector is sensitive to flow variations. Furthermore, the cell is quite fragile and one should be careful when using high flow rates.
RI detector advantages and disadvantages
The refractive index (RI) detector is the most common detector in gel permeation chromatography/size-exclusion chromatography (GPC/SEC). The advantage of this universal detector is that it detects everything; the disadvantage is that it detects everything.
