Many types of HPLC detectors on the market often make us confused. The detector role is essential for an HPLC. If we choose the wrong one, we cannot see and measure the concentration of the analyte correctly.
Then, what are the types of HPLC detectors? What are the differences between them?

HPLC Detector Types

When we want to buy a watch, we certainly think about what activities and goals we will do with it. If you are such an active person, you need a wristwatch that facilitates your routine. A smartwatch is more suitable than a field watch. Identical to watch, HPLC detectors have their purpose.
HPLC detectors serve a different purposes. Foremost for us to know what kind of analyte and the physicochemical of the compound before we choose the detector. Let’s discuss the various types of HPLC detectors!

Charged Aerosol Detector (CAD)

CAD can measure diverse molecules, pharmaceuticals (small and large molecules), biomolecules, food, beverages, polymers, and so forth. This type of HPLC detector is capable of detecting analytes without a chromophore. In addition, CAD can detect non- or semi-volatile analytes. Besides, it can be used for relative quantitation without a reference standard. Another advantage, CAD overcomes the bias that often occurs in other types of detectors. The detection limit of this detector is a high picogram (pg).

Diode Array Detector (DAD)

DAD is only used to analyze an analyte purity or impurity peak elution. Its detection limit is nanograms (ng). One of the UV-Vis absorption detectors is used to detect analytes that have chromophores. The diode arrangement allows the simultaneous acquisition of multiple wavelengths instead of just one. This detector produces data in 3D form (3D field acquisition). DAD provides higher sensitivity and near-uniform response. Suitable for trace impurities analysis.

Variable Wavelength Detector (VWD)

VWD measures the absorption of several wavelengths. VWD detection using a single photodiode. The working principle and types of analytes analyzed by VWD are the same as those of DAD. The linearity and robustness of VWD are above DAD. Moreover, VWD can analyze up to four wavelengths. This type of HPLC detector has a nanogram detection limit. As a result, VWD is more suitable for QC checking procedures. Both VWD and DAD are very easy to use and cost-effective.

Multiple Wavelength Detector (MWD)

MWD is also part of the UV-Vis detector identical to VWD and DAD. Thus, the analyte sample must contain a chromophore. The principle works by utilizing the interaction between material and particular wavelength light. However, the acquisition rate limit is only up to 100 Hz. Unlike VWD, MWD can analyze up to eight wavelengths. You can connect this type of detector to HPLC Vanquish Core. Like VWD, WMD LOD is also a nanogram (ng).

Flourescene Detector (FLD)

FLD has a high level of sensitivity, three to six times higher than UV-VIS detectors. Accordingly, FLD performs by simultaneously detecting several pairs of wavelength. However, the analyte must contain a fluorophore, be derived, or be labeled fluorescent. The LOD of the FLD detector is femtogram to picogram.

Refractive Index Detectors (RID)

RID detects components based on the refraction of light in solution. RID works by measuring the difference between the refractive index of the mobile phase and the sample deflection based on Snell’s Law. Compounds that can be detected are weak chromophore groups, sugars, and polymers.

The LOD of RID is micrograms (μg). Not suitable for gradient methods and also has relatively low sensitivity. RID can analyze analytes without chromophores.

Mass Spectrometry (MS)

The function of the MS detector is to detect and identify compounds with a low picogram (pg) detection limit. It uses different liquid chromatography flow rates to detect compounds, such as nano, micro, capillary, and analytical. MS has a high sensitivity. The range of detection and identification of compounds is wide.

Conductivity dan pH Monitor

PH and conductivity monitors are not HPLC detectors. As the name suggests, pH and conductivity monitors are used to monitor pH gradients and salt. You can apply them in the separation of biopharmaceuticals and the analysis and purification of antibodies & proteins.

Determination of an HPLC detector certainly requires more detailed information. Please, contact us at sales@wiralab.co.id. Our team will help you find the right type of detector for your application.