Neomycin Related Substances

[Chris]

Anyone know of any good methods for the determination of Neomycin related substances? All the ones I can find have mass spec or pulsed ampeometric detection.

Thanks

[Bruce Hamilton]

The reason for the use of PAD or MS is the virtual absence of suitable UV absorption in the molecule and the related substances.

I note that the EP uses PAD, so would suggest that as the first option.

Bruce Hamilton

[krystynakk]

The reason for the use of PAD or MS is the virtual absence of suitable UV absorption in the molecule and the related substances.

I note that the EP uses PAD, so would suggest that as the first option.

Bruce Hamilton

what about elsd detector?

[Bryan Evans]

I remember seeing a poster at ASMS, comparing HILIC vs. IP reversed phase for aminoglycosides. I believe the reversed phase methods
with ODS phase and ion pairing additives (HFBA) showed the best results (in terms of selectivity from matrix).

I'm sorry but I don't have the reference.

[Bryan Evans]

Meant "specificity"

In terms of ELSD, as long as the compound is less volatile
than the mobile phase - shouldn't be a problem.

Maybe someone on the forum can list a good reference
for you

[XL]

ELSD is an "universal" detector for semi- or non-volatile compounds. If you inject "enough" amount of Neomycin related substances (usually higher than 20 ng), you might be able to see it. However, the detection could be heavily affected by sample matrix because of its universality.

By comaprison, PAD is very "specific." In addition, its sensitivity can be several orders of magnitude better than ELSD.

Attached is somewhat related information that you might find useful.
http://www1.dionex.com/en-us/acclaim_li ... 25918.html

Let me know if you need additional information.

[Bryan Evans]

Imtakt has a new LC-ELSD application for aminoglycoside antibiotics.
They separated the analytes on 4 different ODS phases:

http://www.imtakt.com/TecInfo/TI426E.pdf