Fluorescence is the emission of a photon from a molecule after absorbance of electromagnetic radiation at a specific wavelength. The absorbtion of the excitation energy promotes the molecule from the ground electronic state (So) to a higher excitation state (S1). When the molecule returns to the ground state, a photon is emitted. A part of the excitation energy is converted into heat and the energy of the emitted photon is less than the excitation energy as shown in equation 1.

	Eq. 1
Why excite with a Laser?
	Eq. 2
F = Fluorescence Intensity Ia = Intensity of absorbed radiation = Absorption coefficient of the molecule C = Concentration l = Cell thickness V = Illuminated volume k = Konstante Φf = Fluorescence quantum yield

The fundamental equation for fluorescence (equation 2) shows that the fluorescence intensity is derectly proportional to the intensity of the excitation light. In addition, the high energy laser light leades to greater absorbtion because it can penetrate deeper into the sample and can therefore excite more molecules than a Deuterium or Xenon lamp can.

In addition, it should be noted that when CE/CEC or Micro/Nano HPLC, the cell thickness and illuminated volumes are quite small. The concentration of the compound(s) of interest is frequently quite low and the analyst desires the generation of a strong signal. The only way to generate a strong signal is to use a laser which provides a high monochromatic energy density.



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A modular, stand-alone Detector with greater sensitivity than previously obtainable.

ZETALIF provides the highest detection sensitivity for fluorescence compounds. The use of laser technology allows for detection in the sub-zepto mole range. The ZETALIF is the world's most sensitive fluorescence detector. In addition, Picometrics offers the broadest range of lasers and excitation wavelengths

Sensitivity

The use of a laser for excitation, as well other optical considerations leads to detection limits that were previously unobtainable. These improvements are due to a great degree on the use of patented, colinear optics. As an example, a concentration as low as 10-12 M Rhodamin 123 can be detected with a signal/noise ratio greater than 10 (CE mit 75µm ID capillary cell, 488 nm Argon-Ionen-Laser with 10 mW-power).

Flexibility

The modular construction guarantees maximum flexibility with a system that is easy to handle. The ZETALIF detector can be easily incorporated with all separation techniques, such as capillary electrophoresis, CEC, HPLC, Nano-HPLC and Micro-HPLC. The construction allows the use of different cells, lasers and optical filter sets. The optimum wavelength can be chose from a large range of lasers and filter sets.

Typical Applications
Neurochemistry, Pharmacology, Biochemistry, Molecular Biology, Immunology, Trace Analysis in the areas of Drug Metabolism and Pharmacokinetics, Environmental Analysis, Toxicology, Oncology, Analysis of Cosmetics, Foodstuffs and Forensic Analysis.
Applications
The ZETALIF can detect a broad range of compounds via either native fluorescence or by the formation of a fluorescent derivative.
Compounds with Native Fluorescence
Pyren, Aflatoxins	325 nm
Riboflavin	442 nm
Doxo/Daunorubicin	488 nm
Rhodamin	488 nm
Derivative Forming Reagents
Dansyl Chloride	325 nm
OPA	325 nm
NDA	442 nm
CBQCA	442 nm
FITC	488 nm
DTAF	488 nm
NBD	488 nm

For further comprehensive information please contact us or visit the Picometrics website www.picometrics.com

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Measuring Ranges ( RFU )	0-2; 0-20; 0-200
Dynamic Range	Linear over range of 105 (within 2%)
Sensitivity	S/N > 10 for a solution of 10-12 M Rhodamine in a capillary cell 75mm ID and 488 nm Ar-Ion-Laser (10 mW).
Noise	< 0.003 RFU Rhodamine measured with a capillary cell (75mm ID) at 488 nm with an Ar-Ion-Laser (10 mW)
Dimensions and Weight	247x400x217 mm (LxWxH), 8 kg
Operating Temperature	10-35 °C
Power	220-240 V, 0.5 A, 50/60 Hz or 100-120 V, 1 A, 50/60 Hz for the Detector. Laser current dependent on laser (1-20 A).
Signalausgang	1 V (fixed) 100 mV and 1 V (amplified)
Laser	Ar-Ion at 488 nm and 514 nm, He-Cd at 325 nm snd 442 nm. All other wavelenghts, please inquiree
Capillary Flow Cellsen	I.D. 25, 50,……,320 µm

We reserve the right to change Specifications, Design or price without advance notice.

Ordering Information and information concerning the use, technology and integrating the detector into your system is available directly from SunChrom!



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Part Number	Short Description

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