Tris buffer, solution preparation stock

Detection solution 660 pL NBT stock solution + 330 pL BCIP stock solution mixed in 10 mL Tris buffer. Always prepare this mixture fresh before use. 

Unlabeled progesterone (Prog) (Aldrich, 98%) A stock 1 mM solution of progesterone is prepared in methanol (Scharlab, gradient HPLC grade, 99.99%) and stored at 4°C. More diluted solutions are prepared daily by dilution with 0.1 M Tris buffer solution of pH 7.0. 

The calf thymus dsDNA and ssDNA (as lyophilized powder) were obtained from Sigma-Aldrich Company (Germany). dsDNA/ssDNA stock solutions (lOOmg/L) were prepared with TE solution (10 mM Tris-HCl, 1 mM EDTA, pH 8.00) and kept frozen. More dilute solutions of DNA were prepared with 0.05 M acetate buffer solution containing 20 mM NaCl (ABS pH 4.80) ultrapure distilled water. Other chemicals were of analytical reagent grade. 

A stock solution of MDA is prepared as described previously, by dilution of 1 mmol to 100 ml with sulphuric acid (1% v/v). The concentration of MDA is determined by UV-spectrophotometry assuming a molar absorption coefficient of 13700 M-1 cm-1 at 245 nm. This solution is then diluted in 0.1 M Tris buffer (pH 7.0) and brought to... 

Using your Cr aqueous stock solution prepare a solution of approximately 5 x 10-5 m [Cr(phen)3]3+ (aq) in 50 mM Tris-HCl buffer, determining the actual concentration as precisely as possible. Obtain a UV-vis spectrum and a luminescence spectrum of this solution. 

Reagents. A 1.00 X10 4 mol/L stock solution of EHC was prepared in alcohol. HSA (Sigma) was directly dissolved in water to prepare a stock solution of 1.00 g/L, and stored at 0-4°C. The buffer solution was adjusted to 7.4 with 0.10 mol/L Tris and 0.10 mol/L HC1. All reagents were of analytical reagent grade and used without further purification. Doubly distilled water was used throughout. 

Buffer A 20x stock solution (for antigen retrieval) NaCl-Na citrate buffer (2.96 M NaCl, 0.34 M Na3C6H507), pH 7.4. To prepare 1 L in 950 mL ddH20, dissolve 173.3 g NaCl + 88.2 g Tris-Na citrate. Adjust pH and add ddH20 to bring to final volume to 1 L. 

The purification of kid pregastric lipase was described earlier [20]. The surfactants cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), bis(2-ethylhexyl) sodium sulfosuccinate (Aerosol-OT) (AOT), soybean lecithin, Tween 20, sodium taurocholate (NaTC), and Triton X-100 (TX-lOO) were purchased from Sigma. Stock solutions of surfactants were prepared in 50 mM Bis-Tris buffer, pH 6.5, 25°C. The substrates 4-nitro-phenyl butyrate (4-NPB) and tributyrin were also purchased from Sigma. 

Cascade Blue diamine derivatives are soluble in aqueous solution. A concentrated stock solution may be prepared in water, dissolved quickly, and an aliquot immediately added to a buffered reaction medium. For aqueous reactions, 0.1M MES, pH 4.7-6.5, may be used to stabilize the pH during the coupling process. Avoid amine- or carboxylate-containing buffers such as Tris or glycine, since these can compete with the coupling reaction. 

Reaction of AMCA-NHS with proteins proceeds efficiendy in the pH range 7—9. Avoid buffers containing amines that can compete in the coupling reaction, such as Tris or glycine, and avoid imidazole buffers since they promote hydrolysis of the NHS ester. AMCA-NHS is relatively insoluble in aqueous buffers. The compound must be first dissolved in organic solvent prior to addition of a small aliquot to the reaction mixture. A concentrated stock solution may be prepared in DMSO and stored up to 2 weeks refrigerated or frozen without loss of activity. The solid and all solutions of AMCA-NHS should be protected from light to avoid photodecomposition of the fluorophore. 

Hepes is used at 10-25 mM and is added to medium from a stock solution (1 M) whose preparation is described in Appendix 1, Table A1.5. As well as Hepes, other zwitterionic buffers have been used in cell culture medium. TRICINE (lV-[Tris-hydroxymethyl)-methyl]gly-cine, pKa = 7.79 at 37°C) has been used in Eagle s MEM (Spendlove et al., 1971) and in Swim s 577 (Gardner, 1969) and TES, (iV-[(Tris-hydroxymethyl)methyl]-2-aminoethanesulphonic acid, pKa = 7.16 at 37°C) has been used in Eagle s MEM, BME and in medium 199 (Williamson and Cox, 1968 Massie et al., 1972). These buffers are used in varying concentrations (10-50 mM). Eagle (1971) suggests combinations of buffers which can be used to buffer the medium over the range 6.4-8.35. 

Mouse tissue (mouse tail) lysis buffer (2X) 8 M urea, 20 mM EDTA (prepared from a stock solution of 0.5 M, pH 8.0, 1% N-lauroylsarcosine (Sigma-Aldrich, Cat. No. L-9150) (make stock solution, 30%), 0.2 M Tris-Cl, and 0.4 M NaCl. The 2X lysis buffer is diluted to IX with distilled water. Proteinase K is added to 100 pg/mL when needed. 

Standards The stock solution of Apidra is prepared by dissolving about 500 xg (exact weight) Apidra in 5 ml of 0.1 M Tris/HCI buffer, pH 9. This solution (100 ig/ml) is further diluted in insulin free human serum to a concentration of 20.0 ng/ml (nominal value). The standards (10, 5, 2.5, 1.25, 0.63, 0.31, 0.16 ng/ml) are prepared by serial dilution of the stock solution in insulin free human serum matrix (e.g. WBAG Resources GmbH). 

Protein molecular weight standards—Suggested standards are phosphorylase (97,400 Da), bovine serum albumin (66,200 Da), ovalbumin (45,000 Da), carbonic anhydrase (31,000 Da), soybean trypsin inhibitor (21,500 Da) and lysozyme (14,400 Da) at 1 mg/ml each in a single mixture in 0.01 M Tris chloride buffer, pH 7.0 (prepared by dilution of the stock 1 M buffer above). Approximately 2 ml of this solution will be required. 

TE buffer—Prepare a 1 M stock solution of Tris by dissolving 121.1 g of Tris free base in 700 ml of distilled water. Adjust the pH to 7.5 with concentrated HC1. Prepare a 0.5 M EDTA stock solution by dissolving 93 g of Na2EDTA 2H20 in 400 ml of distilled water. Adjust the pH to 8.0 by slowly dissolving in NaOH pellets. Bring the final volume of the solution to 500 ml with distilled water. To prepare the TE buffer, add 1 ml of the 0.5 M EDTA stock solution and 10 ml of the 1 M Tris stock solution to 989 ml of distilled water. 

The assay buffer to determine the activity of experimental agents consisted of 20 mM Tris (pH 8) containing 10 xM ZnCl2. A 1 mM substrate of s-DNP-L-Lys-D-Amp stock solution in DMSO was prepared and selected experimental agents drawn from a reservoir of methyl alcohol diluted with water. 

The acrylamide concentration is chosen for the first dimension (acid gel), and may be 10% for fractionation of RNA mixtures containing maximum chain lengths of about 80 nucleotides (as applied by De Wachter and Fiers to a typical viral RNA partial digest), and is then made twice as high in the second (neutral) gel. The concentration of cross-linker (Bis) is 1/30 that of acrylamide. The buffer in reservoir and gel is 0.025 M citric acid, 6 M urea for the first dimension, and 0.04 M Tris-citric acid, pH 8, for the second dimension. Table 8.3 summarises the concentrations and amounts of stock solutions conveniently used for the preparation of each gel, as well as the catalyst, which is added iimnediately before the gel is poured. 

A stock solution (10 mg/ml) of naphthol AS-MX, or naphthol AS phosphate, or naphthol AS-BI phosphoric acid sodium salt (Sigma) in DMF is prepared and diluted 50 times with 100 mM Tris-HCl buffer, pH 8.2. The solution is stable at 4°C for several weeks (in their original work. Mason and Sammons used naphthol AS phosphate and a buffer of pH 9.0). The substrate solution is prepared by dissolving Fast Blue BBN or Fast Red TR (1 mg/ml) in the naphthol stock solution. 

A 10 mmol L stock coelenterazine solution was prepared by dissolving coelenterazine (Nanolight Technology, Prolume Ltd. Pinetop, AZ, USA) in methanol for use at a final concentration of 10 /tmol L". All coelenterazine solutions were stored at -20 °C and working solutions were kept on ice in the dark during preparation. Diluent buffers comprised distilled water (dH20), Phosphate buffered saline (PBS), Buffer A (10 mmol L Tris [pH 7.8], 1 mmol L EDTA, 0.6 mol L NaCl), 7H9 medium supplemented with Tween-80 with or without 10% OADC (oleic acid, albumin, dextrose, catalase), Luria-Bertani (LB) broth with or... 

Proteins were obtained from various vendors. Stock solutions of 1 mg/ml were freshly prepared in 2% SDS + 2% B-mercaptoethanol. Appropriate dilutions of the stock were made and then diluted 1 1 with a 1.5% agarose buffer composed of 27mM Tris adjusted to pH 8.0 with HCl and 0.1% SDS. The protein-agarose mixture was heated to 95° for 5 minutes and drawn into a capillary tube with an internal diameter of 1.5 mm. After the agarose solidified it was extruded and a piece was run on a one dimension SDS 10-20% gradient gel as previously described. 

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