Sodium hydrogen phosphate

Finasteride was purchased from Soha Helal (Tehran, Iran). Propylene glycol, Span 20, Tween 80, oleic acid, sodium dihydrogen phosphate and sodium hydrogen phosphate were obtained from Merck (Darmstadt, Germany). Transcutol P was donated by the Gattefosse (Lyon, France). The dialysis bags used in the present study was purchased from Tuba Azma Co. (Tehran, Iran). All chemicals and solvents were analytical grade. In addition, fresh double distilled water was used in the experiments.

Tetrachloroauric (ш) acid trihydrate (HAuCl₄·3H₂O), melamine (99%), and potassium ferricyanide/ferrocyanide (K₃[Fe(CN)₆])/(K₄[Fe(CN)₆]) were purchased from Sigma‐Aldrich. 1,2‐Phenylene‐diamine (C₆H₈N₂), graphite powder, sodium dihydrogen phosphate (NaH₂PO₄), sodium hydrogen phosphate (Na₂HPO₄), potassium nitrate (KNO₃), sodium tetrahydroborate, sodium hydroxide (NaOH), potassium chloride (KCl), dimethylformamide (DMF), potassium permanganate (KMnO₄), hydrochloric acid (HCl), sulfuric acid (H₂SO₄), ethanol, methanol, acetic acid, ascorbic acid, l‐histidine, glycine, cyanuric acid, and phenylalanine were bought from Merck. For characterization of modified electrode and investigation of its performance, electrochemical cyclic voltammetry (CV) technique in model solution (5.0 mM Fe(CN)₆^4‐/3‐ in 0.1 M potassium chloride) was used. All aqueous solutions were prepared with double‐deionized distilled water.

L-tartaric acid 150.087 g/mol (LGC, Teddington, UK, batch G1057978, purity 97.9%), meloxicam 351.40 g/mol (batch 4198, purity 99.8%), methanol 32.04 g/mol (Merck, Darmstadt, Germany, purity 99.9%), sodium hydrogen phosphate (Merck, purity 99.8%), and sodium dihydrogen phosphate (Merck, purity 99.5%) were commercially available and used without further purification. All working solutions for the solubility tests were prepared using a deionized water/buffer solution of pH 7.4. To prepare 0.2 L of the phosphate-buffered solution, mix 19 mL of solution 2 M of sodium phosphate monobasic with 81 mL 2 M of sodium phosphate dibasic and bring to the mark with deionized water.

The research objects were 150 samples of natural dry red (Cabernet, Merlot) and white (Aligote, Riesling, Pinot Noir) Russian-made grape wines obtained by traditional technologies from European and hybrid grape varieties by industrial producers “Myskhako”, “Fanagoria”, “Kubanvino”, “UVK”, “Villa Victoria”, “Chateau Taman”, “Chateau la Grand Vostok”, as well as blends based on dry wines and made in experimental conditions “Cabernet Sauvignon”, “Merlot” and “Pinot Noir”. The wines were produced in 2010–2013 (alcohol content - 9–13% by volume, acidity - 4–7 g/dm³).
For chromatographic and electrophoretic studies, analytical standards of proline, arginine, serine, valine, glycine and threonine, 18-crown ether-6, purchased from Sigma Aldrich (Santa Ana, CA, USA) were used. Cyclodextrin, sodium hydrogen phosphate, potassium dihydrogen phosphate, phenylisothiocyanate, sodium carbonate were of analytical purity and were purchased from Merck (Germany), and b-Cyclodextrin, tartaric acid, H₃PO₄, HCl, NaOH, Na₂B₄O₇x10H₂O were purchased from Vekton (Russia).
A stock solution of each analyte (100 mg/L in double-distilled water) was prepared daily, stored at 4 °C and diluted with double-distilled water.

For the cholinesterase inhibitory test assays, DTNB (5,5-dithiobis-[2-nitrobenzoic acid]) (99.9%) and standard anticholinesterase compound galanthamine hydrobromide (>99%) were purchased from Sigma-Aldrich (Steinheim, Germany). The electric eel acetylcholinesterase (AChE, Type-VI-S, EC 3.1.1.7, 425.84 U/mg) and horse serum butyrylcholinesterase (BuChE, EC 3.1.1.8, 11.4 U/mg) were purchased from Sigma (Steinheim, Germany). The substrate of AChE, acetylthiocholine iodide (>99%) from Applichem (Darmstadt, Germany), and the substrate of BuChE, butyrylthiocholine iodide (>99%) from Fluka (Steinheim, Germany) were purchased.
The chemicals and solvents, sodium carbonate, sodium hydrogen phosphate, sodium dihydrogen phosphate, and hexane, dichloromethane, ethylacetate, ethanol, methanol, butanol, and silica gel for column chromatography (1.07734) and silica gel 60 F254 TLC plates (1.05554), potassium hydroxide, sodium sulphate, hydrochloride acid, and diethyl ether were purchased from Merck (Darmstadt, Germany).

Ultra-performance liquid chromatography (UPLC)-grade acetonitrile, isopropanol, methanol, ethyl acetate and purified water were purchased from Biosolve B.V. (Valkenswaard, the Netherlands). Acetic acid, ammonium hydroxide, ammonium acetate and 2-proponal were acquired from Sigma-Aldrich (Zwijndrecht, the Netherlands). Sodium dihydrogen phosphate dihydrate, sodium hydrogen phosphate and sodium acetate were obtained from Merck (Darmstadt, Germany).

All reference and standard chemicals including gallic acid, ferulic acid, p-hydroxybenzoic acid, chlorogenic acid, syringic acid, vanillic acid, sinapic acid, p-coumaric acid, salicylic acid, cinnamic acid, benzoic acid, rutin, kaempferol, catechin, quercetin, 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•), carrageenan, Folin-Ciocalteu reagent and butylated hydroxyanisole (BHA) were acquired from Sigma-Aldrich (St Louis, MO, USA). ELISA kits from Elabscience and all other chemicals and reagents used in this study, such as ferric chloride, trichloroacetic acid, sodium hydrogen phosphate, sodium dihydrogen phosphate and methanol, were of analytical grade unless otherwise specified and acquired from Merck Co. (Darmstadt, Germany).