A rapid and sensitive stability-indicating green RP-HPTLC method for the quantitation of flibanserin compared to green NP-HPTLC method: Validation studies and greenness assessment

A rapid and sensitive stability-indicating green reversed-phase high-performance thin-layer chromatography (SI-G-RP-HPTLC) method was established and validated for the detection of flibanserin (FBN) compared to the stability-indicating green normal-phase high-performance thin-layer chromatography (SI-G-NP-HPTLC) method. The G-RP-HPTLC-densitometry analysis of FBN was conducted using acetone/water (80:20, v/v) solvent system as the mobile phase, while, the G-NP-HPTLC-densitometry analysis of FBN was conducted using ethyl acetate/methanol (95:5, v/v) solvent system. The quantitation of FBN was carried out at λ_max = 204 nm for both of the techniques. The SI-G-RP-HPTLC and SI-G-NP-HPTLC methods were found to be linear in the range of 100–1600 and 200–1600 ng/band, respectively. The system suitability parameters for both of the methods were found to be acceptable for the quantitation of FBN. The SI-G-RP-HPTLC technique was found to be more rapid, accurate, precise, and sensitive for the determination of FBN compared to the SI-G-NP-HPTLC technique. The SI-G-RP-HPTLC technique was observed as more selective and stability-indicating for the determination of FBN in the presence of its degradation products. The FBN contents of commercial film-coated tablets were found to be 98.76% using the SI-G-RP-HPTLC technique, while, the FBN contents of commercial film-coated tablets were recorded as 96.28% using the SI-G-NP-HPTLC technique. The greenness of both of the green methods was assessed using AGREE software which utilized 12 principles of green analytical chemistry. The eco-scales of SI-G-RP-HPTLC and SI-G-NP-HPTLC methods were predicted as 0.86 and 0.80, respectively. The obtained eco-scale values for both of the methods suggested excellent greenness of both of the methods. Based on these observations and validation studies, the SI-G-RP-HPTLC methodology was considered as superior over the SI-G-NP-HPTLC technique for pharmaceutical analysis. Accordingly, the SI-G-RP-HPTLC technique could be utilized for the quantitation and stability evaluation of FBN in commercial products containing FBN.