Of Bromophenol Blue

Procedure. Take an aliquot portion of the unknown slightly acid solution containing 0.1-0.5 mg iron and transfer it to a 50 mL graduated flask. Determine, by the use of a similar aliquot portion containing a few drops of bromophenol blue, the volume of sodium acetate solution required to bring the pH to 3.5 1.0. Add the same volume of acetate solution to the original aliquot part and then 4 mL each of the quinol and 1,10-phenanthroline solutions. Make up to the mark with distilled water, mix well, and allow to stand for 1 hour to complete the reduction of the iron. Compare the intensity of the colour produced with standards, similarly prepared, in any convenient way. If a colorimeter is... 

Similarly, all pH indicators mentioned can be used for measurement of acidic and basic gases. Figure 14 shows the example of deprotonated bromophenol blue when dissolved in silicone and upon exposure to ammonia when the color of bromophenol blue changed from yellow to blue40 41. 

For the cationic surfactants, the available HPLC detection methods involve direct UV (for cationics with chromophores, such as benzylalkyl-dimethyl ammonium salts) or for compounds that lack UV absorbance, indirect photometry in conjunction with a post-column addition of bromophenol blue or other anionic dye [49], refractive index [50,51], conductivity detection [47,52] and fluorescence combined with postcolumn addition of the ion-pair [53] were used. These modes of detection, limited to isocratic elution, are not totally satisfactory for the separation of quaternary compounds with a wide range of molecular weights. Thus, to overcome the limitation of other detection systems, the ELS detector has been introduced as a universal detector compatible with gradient elution [45]. 

Materials Required Benzethonium chloride 0.15 g Chloroform 50 ml bromophenol blue solution (Dissolve with heating 0.2 g of bromophenol blue in 3 ml of 0.1 M NaOH and 10 ml of ethanol (96%). Allow to cool and dilute to 100 ml with ethanol 96%] 50 ml sodium tetraphenyl borate solution (1% w/v in chloroform) 50 ml sintered-glass crucible No 4. 

Prepare a small well containing a mix of bromophenol blue and xylene cyanol in order to follow the migration. 

Sodium dodecyl sulfate (SDS) sample buffer stock solution Dissolve 1.51 g Tris base to 15 ml of distilled water, and then add 25 ml of 50% glycerol into the mixture. Stir to dissolve and then adjust pH to 6.8 with HCl. Dissolve 5 g of SDS in this buffer and make up to 50 ml with distilled water. Dissolve 0.01 g of bromophenol blue and stir overnight. 

Prepare the sample in buffer E with a protein concentration not more than 20 mg/ml. Heat the solution to 95 °C for 2-3 min and supplement with some crystals of sucrose or a droplet of glycerol or 1/10 volume of bromophenol blue in 50% sucrose solution. 

Mix the probe 1 1 with Soln. A and add a trace of bromophenol blue. Fill tbe wells completely with sample. 

Place the slide into a horizontal electrophoresis apparatus, fill the tanks with Soln. A, and connect the small ends of the slide to the electrode tanks by moistened filter paper wicks. Fill the well directed towards the anode with antiserum dilution and pipet antigen solution containing traces of bromophenol blue in that well which is nearby tbe cathode. 

What assumption is made about the relative electrophoretic mobility of bromophenol blue dye and plasmid DNA ... 

The mobility of bromophenol blue must be greater than that of any proteins in the sample. 

In the determination, 2 g of the diisocyanate should be accurately weighed out into a conical flask and 5 ml of chlorobenzene added. In the case of naphthalene diisocyanate, it is recommended that the mixture be warmed slightly to assist dissolution. To this mixture there is then added 25 ml of the standard dibutylamine solution. The reaction is rapid and takes only a few minutes for completion, when a clear solution is obtained. After adding 2 or 3 drops of a 1% alcoholic solution of bromophenol blue and 100 ml of methanol, the excess dibutylamine can be titrated with 1 N hydrochloric acid. 

Evaporation forces the whole sample rapidly towards a straight and narrow zone at the center. This can easily be observed if the serum sample is stained with a trace of bromophenol blue (V7). Only after some time do the j- and y-globulins migrate backward toward the starting line, while the albumin and a-globulin migrate normally forward for some time (Fig. 5). This migration of the fractions is slower than the first rheophoretic movement. 

Procedure Pipet 10.0 mL of the Sample Solution into a 250-mL flask, and add 40 mL of chloroform, 50 mL of Salt Solution, and 10 drops of bromophenol blue TS. Titrate with Tetra-n-butylammonium Iodide Solution to the first appearance of a blue color in the chloroform layer after vigorous shaking. Calculate the percent C2oH37Na07S by the formula... 

Identification Dissolve 500 mg of sample in 5 mL of 1 2 hydrochloric acid, and add an excess of 1N sodium hydroxide. A red-brown precipitate forms. Allow the solution to stand for several minutes, and then filter, discarding the first few milliliters. Add 1 drop of bromophenol blue TS to 5 mL of the clear filtrate, and titrate with 1 N hydrochloric acid to a green color. Add 10 mL of a 1 8 solution of zinc sulfate, and readjust the pH to 3.8 (green color). A white precipitate forms (distinction from orthophosphates). 

Procedure Weigh accurately the quantity of sample specified in the monograph, and transfer it into a 125-mL Erlenmeyer flask. Add 30 mL of Hydroxylamine Hydrochloride Solution, mix thoroughly, and allow to stand at room temperature for 10 min, unless otherwise specified in the monograph. Titrate with 0.5 A alcoholic potassium hydroxide to a greenish yellow endpoint that matches the color of 30 mL of Hydroxylamine Hydrochloride Solution in a 125-mL flask when the same volume of bromophenol blue TS has been added to each flask, or preferably titrate to a pH of 3.4 using a suitable pH meter. Calculate the percentage of aldehyde (A) by the equation... 

Bromophenol Blue TS Dissolve 100 mg of bromophenol blue in 100 mL of 1 2 alcohol, and filter if necessary. 

Hydroxylamine Hydrochloride TS Dissolve 3.5 g of hydroxylamine hydrochloride (NH2OH HCl) in 95 mL of 60% alcohol, and add 0.5 mL of a 1 1000 solution of bromophenol blue and 0.5 N alcoholic potassium hydroxide until a green tint develops in the solution. Then add sufficient 60% alcohol to make 100 mL. 

Hydroxylamine Hydrochloride, 0.5 N (35 g NH2OHHCl per 1000 mL) Dissolve 35 g of hydroxylamine hydrochloride in 150 mL of water, and dilute to 1000 mL with anhydrous methanol. To 500 mL of this solution add 15 mL of a 0.04% solution of bromophenol blue in alcohol, and titrate with 0.5 N Triethanolamine until the solution appears green-blue by transmitted light. Prepare this solution fresh before each series of analyses. 

X SDS/EDTA buffer—Dissolve 3.51 g of Tris HC1 and 0.335 g of Tris free base in 50 ml of 0.5 M EDTA, pH 8.0. Adjust the pH to 7.0 with dilute NaOH or HC1 if necessary. Add 30 ml of glycerol, 10 ml of /3-mercaptoethanol, and 10 ml of distilled water. Dissolve (avoid foaming) 8 g of SDS into this solution, as well as 4 mg of bromophenol blue. Store the solution tightly capped at room temperature. 

X DNA sample buffer—Dissolve 0.25 g of xylene cyanole FF and 0.25 g of bromophenol blue in 70 ml of distilled water. Add and thoroughly mix in 30 ml of glycerol. Store the solution at room temperature. 

Microfluidic Free Interface Diffusion 1 hour Equilibration of Bromophenol Blue... 

Schilling, K. and Waldmann-Meyer, H., The interaction of bromophenol blue with serum albumin and gamma-globuhn in acid medium. Arch. Biochem. Biophys. 64, 291-301, 1956 Cohen, A.H., Temperature jump studies of the binding of bromophenol blue to beta-lactoglobulin in the vicinity of the N-R transition, J. Biol. Chem. 245,738-745,1970 Harruff, R.C. and Jenkins, W.T., The binding of bromophenol blue to aspartate aminotransferase. Arch. Biochem. Biophys. 

There are two possible types of kinetics for the two-step mechanism shown above, in that either the first or second step may be rate-limiting. It is thought that it is most commonly the first, diffusion-controlled step which is rate-limiting, as exemplified by the reactions listed in Table 20. The observed rate process is the formation of the coloured anions of Bromophenol Blue, I, and Magenta E, II, and the coloured cation of Nile Blue, III, viz. 

---