Methylene Blue NDSRI

Guidance, Documents, Resources
1

Does anyone work on Quantification of N-desmethyl-N-nitroso-methylene blue NDSRI in methylene Blue on LCMS/MS ?
We tried to develop the method for the NDSRI but we are getting recovery higher side. Tried various diluents but not succeed.

Thanks
Vivek

2

thanks for sharing , May i know your selection of solvent and LCMS ion precursor type

3

Mobile phase
0.1% TFA in Water
0.1% TFA in Methanol
Diluent mix of both
LCMS ion precursor type ESI+ mass 299.3
Fragment 269.2 & 252.2

4

Hi, Have you tried to increase the sample concentration

5

Yes, If we increase the sample conc. the impurity also increasing. In as such sample impurity is coming near LOQ level.

6

Just for context…

SMILES: CN(C)c1ccc2c(c1)sc-3cc(=N+C)ccc3n2.[Cl-]

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1 Like
7

Hello Vivek,

Good to know that you are working on this NDSRI and would be helpful which limits are applied for this NDSRI in methylene blue API