Simultaneous Spectrophotometric Determination of Imipramine Hydrochloride with Chlordiazepoxide and Nortriptyline Hydrochloride with Fluphenazine Hydrochloride

Simultaneous spectrophotometric determination of fluphenazine HCl and nortriptyline HCl in presence of their potential impurities perphenazine and dibenzosuberone in bulk and pharmaceutical formulation

Fluphenazine HCl (FLU) is an anxiolytic, while Nortriptyline HCl (NOR) is an anti-depressant. They are co-formulated together to treat depression and schizophrenia. Perphenazine (PER) and dibenzosuberone (DBZ) are the pharmacopeial impurities of FLU and NOR, respectively. Four spectrophotometric and multivariate chemometric methods were developed to determine the two drugs together or in presence of their two impurities in their bulk and pharmaceutical formulation. Method (A) is the triple divisor-ratio derivative (TDR) method, where the zero order spectrum of each component was divided by a mixture of the other 3 components, then the peak amplitudes of the first derivative spectra of FLU, NOR and DBZ were measured at 265, 245.4 and 283.2 nm, respectively. Method (B) is the double divisor-ratio difference-dual wavelength (DD-RD-DW) method, in which each component spectrum mixture was divided by a binary mixture of 2 of the interfering components. In the resulting ratio spectra, the amplitude difference is calculated between 2 wavelengths at which the third interfering component has zero difference. Methods (C and D) are the principle component analysis (PCA) and partial least squares (PLS) models. Methods (A and B) failed to quantify PER (FLU impurity), while (C and D) succeeded to quantify all components. The four methods have been applied for the prediction of the FLU and NOR in their pharmaceutical formulation with good accuracy and precision. The proposed methods have been validated according to the ICH guidelines and the results were within the acceptable limits.

Four Greenness Evaluations of Two Chromatographic Methods: Application to Fluphenazine HCl and Nortriptyline HCl Pharmaceutical Combination in Presence of Their Potential Impurities Perphenazine and Dibenzosuberone

Nowadays, when analysts develop a new method, they are taking into consideration the green aspects of the developed method. Two chromatographic methods were developed for the determination of antidepressant pharmaceutical combination nortriptyline hydrochloride and fluphenazine hydrochloride in presence of their potential impurities and the methods were assessed using four tools; eco-scale, analytical greenness profile (AGP), analytical greenness metric approach (AGREE), and green analytical procedure index (GAPI). Method (A) was RP-HPLC, in which the separation was carried out on C18 column (250 × 4.5 mm, 5 µm) by gradient elution using mobile phase consisting of a mixture of water containing 0.1% H3PO4 (pH 2.25) and methanol, at a flow rate of 2 mL/min with DAD detection at 254 nm. Method (B) was TLC, in which the separation was carried out on silica gel TLC F254 plates. The mobile phase used was a mixture of methanol and acetone (9:1, v/v) with UV detection at 245 nm. The proposed methods agreed with ICH guidelines of method validation and were successfully applied for determination of the proposed components in their dosage form and the results were compared statistically to those obtained by the reported RP-HPLC method with no significant difference; which suggests the application of the developed methods for routine quality control analysis of these drugs.