Measurement of Tween 80 in Pharmaceuticals

[KarenJ]

Hi,

Does anyone know of a method for quantitating the levels of Tween 80 (polysorbate 80) in solution formulations? I've seen one reference that uses Evaporative Light Scattering detection. The boiling point of Tween 80 is listed in the MSDS as 100C. Will ELSD work well for an analyte with a boiling point this low?

Karen J

[Mark Tracy]

Tween-80 has various amounts of water in it, hence the low boiling point. Actually, it works well on an evaporative light scattering detector. The bad news is that it is a complex mixture with many peaks. We have run it here on our Acclaim Surfactant column, but I don't have a link to a sample chromatogram.

[JMB]

Karen,

L. M. Nair et al. Journal of Chromatography A
Volume 1012, Issue 1 , 12 September 2003, Pages 81-86

This is probably the ref. that you mention. Chromatography to give single peak, with ELSD is used.

LOQ = 40 ug/mL and LOD = 15 ug/mL are quoted.

JMB

[tom_mizukami]

Tween 80 is a complex mixture, I think I would stay away from HPLC.

You could measure the uptake of a fluorscent dye in or onto tween micelles. Here is a paper http://wwwsoc.nii.ac.jp/jsac/analsci/pdfs/a19_0737.pdf

Of course you could use an HPLC with a restriction capillary or reaction coil instead of a column.

Tom

[JMB]

Tom,

Yes, Tween 80 certainly is a complex mixture, however the reference that I cited describes the use of a very steep gradient (MeOH 30 ---> 90 %, 4 min) on a C-18 column to compress the many peaks into a single (fronting) peak for quantitation purposes.

JMB

[tom_mizukami]

Hi JMB,

I'm not doubting that it can be done, but why bother with a column at that point.

Tom

[JM]

Why you need to quantify a excepient , which is mix of several components?? normally this type of excepient ( like Tween-80 and Cremophor ) not quntified but a id test is done . If you try to elute all of the tween-80 componets by high organic chances are that all your drug product will also elute. Also pls note this type of natural originated exceipient components vary with the time and region .

JM

[KarenJ]

JM,

We aren't qualifiying the Tween 80 as an excipient. We have been asked to compare the levels of Tween in several finished parenteral products.

Thanks,

Karen J

[JMB]

Tom--I think Karen needs to measure Tween 80 in formulations, so cannot use FIA since ELSD is not selective.

JM--I take the point about drug also eluting at high %ORG, however the paper shows a satisfactory example. Their description of the "gradient" is a little ambiguous--seems probable that they run at 30%ORG for 4 min then step to 90%ORG to drive off the Tween as a single peak while leaving the drug on the column (rather than a linear 30 --> 90% org ramp).

Karen-- IF you try the method and IF it works for your API/Tween formulation please let us know.

Thanks,

JMB

[KarenJ]

Thanks to everyone for their input. I will let you know if we end up trying this.

KarenJ