Analysis of Aspirin and Dipyridamole in a Modern Pharmaceutical Formulation-Drug Release Study and Permeability Assessment

Oral administration of dipyridamole (DIP) with acetylsalicylic acid (ACA) is recommended in thromboembolic conditions or for the treatment of myocardial infarction and stroke. The present study presents an alternative dosage form of these two active ingredients, consisting of a honey core and a dark chocolate coating. The composition masks the bitter taste, is palatable and ensures compliance of a wide range of patients, mainly pediatric. For the simultaneous quantitative determination of the analytes, a Diode Array Detector/Fluorescence Detector (HPLC-DAD/FLD) method was used with a C18 column (250 mm × 4.6 mm, 5 μm) and an isocratic two-phase system (A: H2O 0.2% formic acid—B: Acetonitrile-H2O 90:10 v/v) 65:35 v/v. The method was validated according to ICH guidelines (r2 > 0.999, RSD < 2.3%, % Recovery > 95.4%), and a stability study of the two active ingredients as well as salicylic acid (SAL), which is a hydrolysis product of ACA, was followed. Finally, a digestion protocol (oral cavity–stomach–intestine) for edible materials was applied to determine the release rate of ACA, DIP and SAL in the gastrointestinal tract, while an in vitro permeability study (Papp) was subsequently performed in Franz cells. The results show satisfactory behavior of ACA and DIP and provide a trigger for further studies of the formulation.