How sensitive is the ion exchange LC method to pH in: Rilpivirine concentrations in seminal plasma in HIV infected patients, Victoria Watson, et al?

11 November 2014 1 3K Report

I am trying to reproduce the chromatography described in this document and am consistently eluting my compound when switching back to the A solvent. I have purchased a second column and remade solvents several times. I am experiencing very high carry over and am not seeing TFV-DP until well after I transition back to the A solvent. Any troubleshooting advice is appeciated.

Conference Paper Rilpivirine concentrations in seminal plasma in HIV infected patients

Victoria Watson

Dear Andrew

I am a little confused? The conference paper you have highlighted re: Rilpivirine concentrations in seminal plasma in HIV infected patients does not provide a LC-MS/MS assay detection for TFV-DP.

If you are however looking at the TFV-DP method from : Development and validation of a LC-MS/MS assay to quantify intracellular tenofovir-diphosphate (TFV-DP) and emtricitabine-triphosphate (FTC-TP), then the answer is 'extremely sensitive'. The full methodology can be found in my PhD Thesis, if you would like me to email you a link to this please email contact me at [email protected]

Kind regards Vicky

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