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EKY
Junior

Thailand,
2019-01-04 03:08

Posting: # 19727
Views: 206
 

 Distribution to erythrocytes of Methylphenidate [Bioanalytics]

According to available data that methylphenidate and its metabolites are distributed between plasma (57%) and erythrocytes (43%) in blood.

In the bioanalysis for quantification of methylphenidate in plasma, there are some hemolysis samples.

Has anyone experienced that hemolysis samples (plasma) affect the bioanalysis or the reported plasma concentrations?

Can the respective plasma concentrations from hemolysis samples be fallacious?

Best Regards,
Ohlbe
Hero

France,
2019-01-06 19:07

@ EKY
Posting: # 19736
Views: 139
 

 Distribution to erythrocytes of Methylphenidate

Dear EKY,

» According to available data that methylphenidate and its metabolites are distributed between plasma (57%) and erythrocytes (43%) in blood.

If I interpret correctly what you wrote, concentrations are comparable in plasma and erythrocytes. So hemolysis will not release massive amounts of the drug or metabolites in plasma, contrary to e.g. ciclosporine.

» Can the respective plasma concentrations from hemolysis samples be fallacious?

Yes, possibly, by other ways. If you are using LC-MS/MS, you may have differences in matrix effects in hemolysed samples, but you are supposed to check for this during method validation. If you are using HPLC/UV, you may get chromatographic interferences. Whatever the method, you may have problems with recovery, or with analyte stability (see for instance this paper).

Regards
Ohlbe
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