Fluorescent Detector???

[rick1112]

Hi

We are planning to procure a Fluorescent Detector for HPLC. I would like to know what is the best detector available?
Presently we have two main detector in consideration Agilent 1200 (P/N G1321A) and Water 2475 detector?
If any one of you have practical experience in using Fluorescent Detector would like to know which one is preferable?
Also would like to know what are the most important specification I want to consider when procure this detector??
Any suggestion in this regard will be very valuable

Thanks a lot

[Mark Tracy]

There is more to buying an instrument that technical specifications.

Which software will you use for instrument control? Third-party software often does not support all the features that the vendor's own software does.

Do you trust your local Agilent or Waters service engineers? Sooner or later you will need service. Will you be putting it on a service contract? Read the fine print.

[juddc]

What's most important to you?

Sensitivity? Reliability? Cost? Ease of maintenance? User friendliness?

What data system are you using?

What's your relationship with each vendor?

How do the respective vendor's service staffs compare in your area?

How much does a service agreement cost and what does it cover?

FYI, I have a precursor to the 2475 and it's a good machine, with sufficient sensitivity for my purposes, though it's getting a bit old and I'd presict that a newer design would give better sensitivity. I've found Waters support for the machine to be quite good despite the age of the thing. I got mine for free and I run Waters software, however, so I never did a comparison.

[Mark Tracy]

It is difficult to compare "sensitivity" of fluorescence detectors since there are so many variables. One measure that is often used is the S/N ratio for the Raman scattering line of water; this does not depend on the particulars of the chromatography.

Is there a specific application that you will be doing, or is this a general purpose instrument? If it is specific, you might be able to get a demonstration of your method run; you might not, it depends on how hungry the sales rep is.

Fluorescence detectors have a greater degree of unit-to-unit variability in their S/N performance than do UV or PDA detectors. Things have improved in recent years, but not as much as we all would like.

[rick1112]

We are procuring the instrument for basically carbohydrate analysis, such as, monosaccharide analysis, oligosaccharide analysis, glycoproptein profiling etc…
We also would like to explore the possibility of using the detector in protein and peptide analysis…
So based on the above mentioned could anyone suggest the suitable detector..?

Service and vendor support for both the detectors (Waters and Ailent) are good, can anyone tell which of the detector are commonly used..?

[HW Mueller]

Over 10 years ago I got a spectrometer (Hitachi) for which a flow-through cell was available. At that time its sensitivity was considerably highr than for any HPLC fluorescence detector on the market. Furthermore, it is easily changed over to normal spectrometer function, which was/is a desired fearture. It also has much more possibilities than detectors, even when compared to modern ones as far as I can tell. So thre are difficult choices to be made.

[AdrianF]

Some years ago I had a Jasco detector which was excellent - I believe the waters detector was a rebadged Jasco at a higher price.
I have copied this info from their website.
I note that it can be adapted for chemiluminescence which is a fascinating technique
The JASCO Model FP-2020 Intelligent Fluorescence Detector is recognized as the industry's most sensitive detector with a signal-to-noise ratio of better than 350:1 for the Raman water peak. The FP-2020 covers a wide wavelength range both for excitation and emission from 220 to 700 nm (~ 900 nm with an optional PMT) with proven stability. Versatile time-programming capabilities are provided for wavelength, response, gain, spectral scan, etc., permitting highly selective detection of various compounds. A rapid scan feature allows on-the-flow spectral acquisition for both emission and excitation spectra without interrupting the chromatographic elution. A specially designed chemiluminescence attachment and capillary electrophoresis cell are optionally available.

[rick1112]

Hi

Thank you all for the reply…
I have this one question…some of you have mentioned “the S/N ratio for the Raman scattering line of waterâ€

[Mark Tracy]

Water is not fluorescent, but it does have strong vibrations in the IR . Raman scattering is a phenomenon where a photon strikes a molecule, transfers some energy to a vibrational mode and bounces off with a lower wavelength. The advantage of this is that water does not wear out the way a fluorescent dye does after continuous exposure to intense light. Also water is available everywhere.

So the S/N test measures the ratio of two emission wavelengths, one at the Raman scattered wavelength, one slightly higher at the baseline of the spectral peak.

Each manufacturer sets their own specification for this.

[rick1112]

dear AdrianF

i would like to know if JASCO Fluorescence detector for HPLC FP-2020 is taken over by waters??(you wrote:-Some years ago I had a Jasco detector which was excellent - I believe the waters detector was a rebadged Jasco at a higher price. )

i would like to know this as we have to comunicate with waters vendor regarding this???

thanks a lot

[AA]

The previous generation of Waters fluorescence detector (the 474) was an OEM product from another company (not sure who). The Waters 2475 is (was) designed and built only by Waters. And, as as matter of interest, the 2475 contains some of the biggest breakthroughs in fluorescence detector design in 20 years. I would disagree with a previous poster that the JASCO Model FP-2020 Intelligent Fluorescence Detector is recognized as the industry's most sensitive. I would put a 2475 under real world conditions using a variety of applications up against any other fluorescence detector as the most sensitive fluorescence detector out there.

AA

[AA]

Just for fun I checked the spec:

As the previous poster proudly mentioned:The JASCO Model FP-2020 Intelligent Fluorescence Detector is recognized as the industry's most sensitive detector with a signal-to-noise ratio of better than 350:1 for the Raman water peak.

Waters 2475 signal-to-noise ratio of >1000:1 for the Raman water peak.

1000 is usually better that 350, if sensitivity is what your after.