All used chemicals were of extra-pure analytical reagent grades. High molecular weight poly (vinyl chloride) (PVC), polyvinyl butyral (PVB), methacrylic acis (MAA), ethylene glycol dimethacrylate (EGDMA), single-walled carbon nano tubes (SWCNTs), venlafaxine hydrochloride, desvenlafaxine hydrochloride (ODV.HCl) and 2-nitrophenyl octyl ether (o-NPOE) were purchased from Sigma Aldrich (St. Louis, Mo, USA). Tetrahydrofuran (THF), benzoyl peroxide (BPO), dimethyl sulfoxide (DMSO) and methanol were obtained from Fluka AG (Buchs, Switzerland). The different dosage forms were collected from local pharmacies, which are commercially expressed as Pristiq (76 and 152 mg/tablet) for ODV.
The reference method was the reversed-phase liquid chromatographic method for the quantification of desvenlafaxine [6 (link)]. A total of 20 μL of the sample was injected into a column C18 (5 μm, 250 mm × 4.6 mm i.d.). The amount of ODV was determined using a UV detector operated at a wavelength of 228 nm
Stock solutions of 10−2 M desvenlafaxine hydrochloride were prepared by dissolving 0.38 g of the salt drug in 100 mL of double distilled water. Serial dilutions occurred to obtain different concentrations of the drug (10−2–10−7 M), using 10 mM phosphate buffer at pH 6.0. All solutions were kept at 4 °C.
The reference method was the reversed-phase liquid chromatographic method for the quantification of desvenlafaxine [6 (link)]. A total of 20 μL of the sample was injected into a column C18 (5 μm, 250 mm × 4.6 mm i.d.). The amount of ODV was determined using a UV detector operated at a wavelength of 228 nm
Stock solutions of 10−2 M desvenlafaxine hydrochloride were prepared by dissolving 0.38 g of the salt drug in 100 mL of double distilled water. Serial dilutions occurred to obtain different concentrations of the drug (10−2–10−7 M), using 10 mM phosphate buffer at pH 6.0. All solutions were kept at 4 °C.