High molecular weight poly vinyl chloride

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.

All reagents were purchased from Sigma Aldrich unless otherwise indicated: ruthenium (III) chloride, sodium alginate, high molecular weight chitosan, acrylamide, MBAA, acetic acid, high molecular weight poly (vinyl chloride), valinomycin, bis(2-ethylhexyl) sebacate, tetraphenyl borate, cyclohexanone, N,N′-methylenebisacrylamide, and N,N,N′,N′-tetramethylethylenediamine. Filter paper and all pH buffer solutions were purchased from Fisher Scientific. A Wio Terminal microcontroller was purchased from Seeed Studio. A peristaltic pump and resistors were purchased from Cool Components. A 10 µF capacitor was purchased from RS Components. Arduino pH-4502C pH meter was purchased from Morden Store. Screen-printed electrodes were purchased from Saida Technology. Compost was purchased from Mokuzai. Finally, tomato seeds (Gardener’s Delight variety) were purchased from Thompson and Morgan.

Ephedrine sulphate (EPH) was provided by (Chemical Industries Development CID, Cairo, Egypt). Tetrahydrofuran (THF) was purchased from (Scharlau, the Lab Sourcing Group, Barcelona, Spain). High molecular weight poly(vinyl) chloride (PVC), dibutyl phthalate (DBP), dioctyl phthalate (DOP), calix[4]arene-25,26,27,28-tetrol (CX-4), calix[6]arene (CX-6), calix[8]arene (CX-8), aniline were all purchased from (Sigma Aldrich, Missouri, USA). Sodium tetraphenylborate of purity 99% (TPB), 12-molybdophosphoric acid (PM), tricresyl phosphate (TCP), 2-nitrophenyl phenyl ether (NPPE), 2-nitrophenyl octyl ether (NPOE), and ammonium reineckate (AR) were all purchased from (Alfa Aesar, Massachusetts, USA). Tungstophosphoric acid hydrate (PT) was purchased from (Merck, Darmstadt, Germany). β-Cyclodextrin (β-CD) was purchased from (Acros Organics, New Jersey, USA). Potassium dihydrogen phosphate, prepared as 50 mM in distilled water, hydrochloric acid, and sodium hydroxide were purchased from (El-Nasr Pharmaceutical Chemical Company, Cairo, Egypt). Royal Regime Tea® bags, each tea bag contains 20% Cichorium intybus herb, 30% Cassia angustifolia leaves, and 50% Foeniculum vulgare fruits, batch # 12937, manufactured by Ottoman-Cairo ARE (Royal Herbs), Egypt. A herbal mixture of unknown composition purchased from a local apothecary.