Milli Q water purification system

Deionized water from a Milli-Q water purification system (Millipore Co.) Acetonitrile-water (4 1, v/v) dilute 200 mL of water to 1 L with acetonitrile Dow Corning Antifoam B emulsion Eisher No. CS-283-4... 

Deionized water from a Milli-Q water purification system (Millipore Co.)... 

Water was purified by using a Milli-RO-4 and a Milli-Q water purification system (Millipore Corp., Bedfort, MA 01730, USA). Unless otherwise stated Milli-Q-water quality was used. 

All solutions were prepared from analytically pure substances and deionized water (Millipore, Milli Q water purification system). Hg/HgO/1 M NaOH (E = 0.14 V) and Hg/Hg2SO4/0.5 M H2SO4 (E = 0.68 V) served as reference electrodes and were attached outside of the electrochemical chamber. All electrode potentials are given in reference to the standard hydrogen electrode (SHE) and are corrected for liquid junction potentials if necessary. 

Hyperforin (containing traces of adhyperforin) was obtained form Dr. W. Schwabe Pharmaceuticals (Karlsruhe, Germany). Methanol and acetonitrile were purchased from Caledon (Georgetown, ON, Canada) in HPLC-grade quality. Purified water from a Milli-Q water purification system (Millipore, Bedford, MA) was used. All other solvents and reagents (Tris buffer, ascorbic acid, formic acid and ammonium formate) were obtained from Sigma-Aldrich (Missisauga, ON, Canada). 

Simvastatin and lovastatin (internal standard) were obtained from U.S.P. Both hydrolyzed compounds (simvastatin acid and lovastatin acid) were obtained from Bristol-Myers Squibb Pharmaceutical Research Institute. Acetonitrile (in HPLC grade quality) as well as formic acid (88 %) were ordered from VWR Scientific (Piscataway NJ USA). In addition to that, glacial acetic acid and sodium acetate trihydrate (both ACS grade) were purchased from Baker JT (Phillipsburg NJ USA). Purified water from a Milli-Q water purification system (Millipore Bedford MA USA) was used. Blank plasma was obtained form Bioreclamation (Meadow E, NY USA). 

Sodium (Na), potassium (K), magnesium (Mg), and calcium (Ca), concentrations were measured by atomic absorption spectrophotometry (Perkin Elmer 2380 equipped with deuterium background corrector). Cd, Zr, and Cu concentrations were obtained in a quartz cell, by differential pulse anodic stripping voltammetry (DPASV) with a assy carbon thin-film mercury covered electrode (Tacussel polarographic equipment fitted with a Tacussel EDI type electrode). Pure water was produced by a Milli. Q water purification system (Millipore). Chlorate, sulfate and carbonate were measured using classical methods. 

The solvents were HPLC grade acetonitrile, EM OMNISOLV solvent, (EM Science, N.J.) and distilled, deionized water using a MILLI-Q water Purification System (Millipore Corp., MA). The ammonium acetate used to prepare the 0.5M solution which is added postcolumn to aid the thermospray ionization was Baker Analyzed Reagent (J. T. Baker, NJ). 

Reagents and Materials. Deionized water was obtained from a Millipore Milli-Q water purification system. Triazine standards were received from the U.S. EPA Pesticides and Industrial Chemicals Repository, Research Triangle Park, NC 27711. Immunoassay kits were supplied by ImmunoSysterns, Inc., 4 Washington St., Scarborough, ME 04074. 

The solutions of Cd in 1 M NaCl were prepared using Cd(N03)2 -4H20 (MERCK, pro analysi), NaCl (MERCK, pro analysi) and high-purity water which was obtained by passing distilled water through a Milli-Q water purification system. A supporting electrolyte of 1 M NaCl was used in all the experiments. 

The electrolyte solutions were prepared by use of water purified from deionized water with a Milli-Q Water Purification System. Chemicals (H2SO4 and alcohols) were of reagent grade and used without further purification. The electrolyte solution in the cell was in most cases stirred during measurements. The concentration unit, mol/dm, is abbreviated as M in the present work. 

The purification of acetonitrile was performed by distillation with CaH2 and P2O5 as drying agents. The concentration of water was analyzed by a gas chromatograph. Synthesized tetraethylammonium perchlorate (TEAP) [13] was used as the electrol e. Water was purified with a Milli Q Low-TOC system (Millipore) after distillation. 

Reagents. Acrylamide (Aldrich Chemical Company) was recrystallized from acetone twice before use. Electrophoresis grade sodium dodecyl sulfate (SDS) (Polysciences, Inc.) was used without further purification. Distilled water was purified additionally by treatment with a water purification system (Milli-Q, Millipore) to give water with a resistivity of greater than 18 Mft-cm. 

All chemicals used are of analytical-reagent grade, and water is obtained from a Millipore Milli-Q purification system. 

The polyelectrolytes used in this study are displayed in Table 1. Hydrophobic flexible polyelectrolyte molecules of poly(methacryloyloxyethyl dimethylbenzylammonium chloride) (PMBQ) with a molecular weight of 4.2 Mio g/mol was synthesized by free radical polymerization in water solution as described elsewhere [18,19], Poly(so-dium styrenesulfonate) (PSS) with molecular weight of 70 000 g/mol was purchased from Aldrich and was used without further purification. Water purified and deionized (reverse osmosis followed by ion exchange and filtration) by means of Milli-RO 5Plus and Milli-Q Plus systems (Millipore GmbH, Germany) was used as a solvent. 

Aldrich Chemical. (Milwaukee, WI). 1-Pyrenecarboxyaldehyde was from Lancaster Synthesis (Lancashire, England). All other reagents were of analytical or guaranteed reagent grade and used without further purification. Water was purified using a Milli-Q reagent system (Millipore, Bedford, MA). 

Water is obtained from a Milli-Q purification system (Milli-pore, Bedford, NA, USA). 

Reagent-grade p-ATP (p-Aminothiophenol or 4-Aminothiophaiol, 90%) was obtained from Aldrich Chemical Compmiy and was used without finther purification. Other reagents used in the experiments were of analytical reagent quality. Solutions were prepared using deionized water purified by a Milli-Pore Milli-Q purification system. 

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