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- Posts: 74
- Joined: Tue Apr 12, 2011 9:13 am
Hello,
is there anybody who already made the experience that analyzing a powder mixture of direct compressed tablets results in a lower assay as the assay obtained when resulting tablets are analyzed?
My expectation was that the assay of the tablets might be somewhat lower based on extraction problems due to non-complete tablet disintegration.
The samples are extracted with mobile phase:
- 2 g sodium octane sulfonate / 300 mL, pH 3.5 (acetic acid)
- 260 mL of this solution are mixed with 740 mL of MeOH
I use an ACE 3 C18 column; flow = 1.0 mL/min; 240 nm
No problems with injection precision.
The chromatorgraphy per se look ok.
Powder: within spec
Tablets: OOS
Tablets contain mainly lactose and povidone, magnesium stearate as lubricant.
Thank you very much for your help; a similar problem might already have been solved by anybody, perhaps.
Florian
is there anybody who already made the experience that analyzing a powder mixture of direct compressed tablets results in a lower assay as the assay obtained when resulting tablets are analyzed?
My expectation was that the assay of the tablets might be somewhat lower based on extraction problems due to non-complete tablet disintegration.
The samples are extracted with mobile phase:
- 2 g sodium octane sulfonate / 300 mL, pH 3.5 (acetic acid)
- 260 mL of this solution are mixed with 740 mL of MeOH
I use an ACE 3 C18 column; flow = 1.0 mL/min; 240 nm
No problems with injection precision.
The chromatorgraphy per se look ok.
Powder: within spec
Tablets: OOS
Tablets contain mainly lactose and povidone, magnesium stearate as lubricant.
Thank you very much for your help; a similar problem might already have been solved by anybody, perhaps.
Florian
