Abstract:
The current study represents a bioanalytical method for the estimation of rhein (Rh,
an active metabolite of diacerein, DIA) in rats treated with novel DIA eutectics to
investigate the pharmacokinetics of DIA. A simple protein precipitation technique
was used to extract Rh and the internal standard (IS), p-aminobenzoic acid, injected
into a Phenomenex Gemini C18 column. The separation was achieved by a gradient
elution comprising ammonium acetate (10 mM; pH 3.0) and acetonitrile in an 18 min
run time at a flow rate of 0.8 ml/min with retention times of 11.8 min (Rh) and
5.9 min (IS). The results revealed that the proposed method is linear over a range of
200–20,000 ng/ml (r
2 > 0.9988) of Rh and is precise and accurate. The method was
fully validated as per the US Food and Drug Administration guidelines and a pharma-cokinetic study in rats was performed for Rh following oral administration of the pure
DIA and newly developed eutectics. Therefore, the present method could be used to
estimate DIA to illustrate a comparative pharmacokinetic analysis. This can also be
applied to its related multicomponent formulations for future studies.
