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One Detector Covers All UV/Visible Applications

Universal UV/Visible Detector

WaveQuest the ultra fast scanning Dynamic Absorbance Detector (DAD) is a major advance in UV-visible detector design, offering the capabilities of a Photo Diode Array (PDA) detector with greatly improved performance when used for chromatogram monitoring.

Very high speed scanning of eluting peaks, “on the fly”, makes purity checks, the determination of optimum monitoring wavelengths for unfamiliar peaks (lambda max scans), and compound identification of peaks using library spectra all possible with considerable cost saving.

CE 4300 Dynamic Absorbance Detector

WaveQuest the new CE 4300 Dynamic Absorbance Detector (DAD) for ultra fast scanning, part of the Adept HPLC range from Cecil Instruments, offers all the spectral facilities of Photo Diode Array detectors, with better noise and drift performance, particularly important when used to monitor and quantify chromatograms.

The CE 4300 has a double beam optical system in which the dispersed radiation is dynamically scanned across the detectors in the manner of a UV-Visible double beam spectrophotometer at ultra fast speeds – up to 1000nm/second.

All components of the detector – monochromator, optical system, lamp optics, detector optics and signal processing software have been carefully optimised to provide unprecedented performance in both wavelength scanning and single or multi-wavelength monitoring.

The lower noise level when monitoring a chromatogram makes accurate measurements at the highest sensitivities possible when measuring very low concentrations.

The lower drift, as much as 20 times lower, gives flat chromatogram baselines making integration of peaks more accurate, particularly at high sensitivities.

Taper Beam Optics

Taper beam optical imaging at the flowcell, with all transmitted energy reaching the detector, provides maximum energy collection. The result is minimal baseline wander due to changes in the solvent refractive index during gradient formation.

Performance Validation

Validation of detector performance is carried out conveniently, using the instruments standard software. A Holmium Oxide filter is automatically inserted in the optical path when the calibration routine is selected.

Bandwidth validation is automatic, using the Deuterium emission line at 656.1nm. Absorbance accuracy is checked using filters traceable to NPL standards.

New Super Fast Performance

WaveQuest the CE 4300 Dynamic Absorbance Detector (DAD), is an ultra high speed scanning powerful alternative to Photo Diode Array detectors.  This UV/Visible double beam detector enables high quality  HPLC method development, purity determination and R & D and Variable Wavelength Monitoring. Dual and some other multiple wavelength monitoring and wavelength programming are also provided.

Analysts can perform highly detailed spectral scans and remarkably sensitive and precise quantitative analyses within same chromatographic elution.

The design is based on a double beam spectrophotometer concept with ultra fast wavelength scanning over the range 190-700nm.

This dynamic scan provides UV spectra in only 200mS, previously only possible using the static optical system of a PDA detector.

Powerful signal processing software has been developed which enables very high quality “on-the-fly” scans to be triggered by eluting peaks without the peaks being degraded.

Spectral data is transferred by Cecil’s DataStream software to a PC workstation where the same software offers spectral manipulation and processing, library facilities and the export of data to applications such as Excel, word etc. All data may be stored on disk.

Eluting peaks may be integrated at the same time as purity and peak identification is carried out. Quantitative evaluation and reporting is carried out by Cecil’s CE 4900 PowerStream software, which is combined with DataStream software.

Chromatogram of Sudan I, Sudan II, Sudan III and Sudan IV and the Simultaneous Spectra of the Eluted Peaks

WaveQuest Ultra-Fast Scanning HPLC UV/Visible Detector

Photodiode array UV-Visible detectors do provide a means of identification, but often do not provide the required high sensitivities to UV/Visible chromophores. The drift level of drift typical of photodiode array detectors is generally too high to allow unattended autosampler runs, so they have often are used in conjunction with variable wavelength UV-Visible detectors. This uses up valuable analytical time and requires the use of two separate detectors.

With the WaveQuest, analysts can perform detailed spectral scans and highly sensitive quantitative analyses on the one single detector.  Extra time can be saved as the WaveQuest will provide detailed spectral information and highly sensitive and precise quantitative information within the same chromatographic elution.

Because the WaveQuest is a double beam detector with silicon diodes, a higher degree of stability arises, than that seen with traditional photodiode array detectors.  This greater stability of the WaveQuest detector enables lower noise and drift values, compared to those associated with  traditional photodiode array detectors.

The WaveQuest detector eliminates the need for the use of two separate UV/Visible HPLC detectors.  Hence, every UV/Visible HPLC system can be used to perform complex, reproducible and accurate qualitative and quantitative method development.  The ultra low drift of the detector allows for  unattended weekend and overnight autosampler HPLC runs.

The WaveQuest, which is less expensive than a Photodiode Array Detector (PDA) detector, therefore has a double cost advantage.

By spectrally scanning a chromatographic peak, up to eight times, eight spectra can be visualised of a single chromatographic peak.  

The WaveQuest detector uses DataStream spectral software.  This software contains a spectral library, where previously obtained spectra are stored.  A recently obtained spectrum may be automatically compared to the contents of the spectral library in an instant.

The image below shows a chromatogram of 16 polyaromatic hydrocarbons, designated as priority pollutants in water.  The spectra of each of the eluted peaks is shown on the right hand side of the image.

The WaveQuest may be added to most third party modular HPLC systems and provides an easy instrumental option in the analysis of UV/Visible chromophores.