ESA Biosciences, Inc.

April 10, 2006
Fluorescence Detector Uses 3-D Optical Alignment

ESA Biosciences’ Model 530 High Sensitivity Fluorescence Detector is designed as modular HPLC detectors. It features programmable emission and excitation wavelengths, an easy-to-use control pad, automatic lamp startup/shutdown, pre-aligned lamps for easy changeover and internal self-diagnostics. In addition, it has been optimized for use with ESA's Coulometric electrochemical detection system.

The unique three-dimensional optical alignment technologies used in the Model 530 significantly reduces loss of light and provides high sensitivity in fluorescence measurement. Compounds that exhibit strong fluorescence are likely to be detected at concentrations nearly two orders of magnitude lower than UV-Vis absorbance. With this "bright" optical system, the Model 530 detector can provide a signal-to-noise ratio of over 600.

The detector can be operated as stand-alone module via the supplied control pad or through integration into the EZChrom Elite for ESA Chromatography Data System. Automatic wavelength calibration and documentation within EZChrom Elite for ESA software make it easy to comply with government regulations. And, control of external device functions is provided through programmable contacts.

The beam from the Xenon lamp converges on the excitation monochromator and disperses over a concave diffraction grating structured for minimal light loss. The programmed wavelength then passes through the variable exit slit. The sample in the flow cell is excited and the resulting fluorescence (emitted radiation) enters an emission monochromator. The selected emission wavelength strikes a measuring photomultiplier where the intensity of the excitation beam is measured as a function of time.

You can select from a wide range of wavelengths and functions to collect and save excitation/emission spectra. Time programming for excitation/emission wavelengths is supported. The slit width is adjustable between 15 nm and 30 nm, providing greater sensitivity. Detection wavelengths may be time-programmable for optimum detection sensitivity of each analyte.

Automatic lamp shutdown during inactive periods increases overall lamp life. Lamp usage is easily monitored through the front panel keypad and display. Simple programming is provided for wavelength scanning and range changes during an analytical run.

Long-life replacement lamps and accessories are also available.