Saturation centrifugal filtration

Solid ammonium sulfate is added to the solution to 35% saturation. After filtration, ammonium sulfate is added to the filtrate to 95% saturation. The respiratory components are precipitated. The precipitate is collected with the aid of Hyflo Super-Cel and is dissolved in distilled water and centrifuged to remove the Hyflo Super-Cel. The resulting supernatant is dialyzed against running water for 1 day at below 10°C. The insoluble matter formed during dialysis is removed by centrifugation. 

Barium nitrate is prepared by reaction of BaCO and nitric acid, filtration and evaporative crystallization, or by dissolving sodium nitrate in a saturated solution of barium chloride, with subsequent precipitation of barium nitrate. The precipitate is centrifuged, washed, and dried. Barium nitrate is used in pyrotechnic green flares, tracer buUets, primers, and in detonators. These make use of its property of easy decomposition as well as its characteristic green flame. A small amount is used as a source of barium oxide in enamels. 

Add 24.3 g solid ammonium sulfate per 100 ml EDTA-filtrate (yields a 40% saturation) and stir at 4 °C for 30 min. Collect the precipitate by centrifugation. Wash the pellet once with 30% saturated ammonium sulfate (3 vol. Soln. E -i- 7 vol. ddH20), spin down again and dissolve the precipitated IgY in a small volume of Soln. A (about 1/10 of the original yolk volume). Dialyze against TBS and determine the IgY content spectrophotometrically. 

Dry-cleaning machines are usually provided with a centrifugal pump to force the liquid through a filter, and with a blower to move and filter the solvent vapour phase also. After the cleaning cycle, the solvent is drained from the cleaning chamber and may be reused, provided that the level of dissolved contaminants is not approaching saturation, otherwise it is regenerated by distillation or cleaned by mechanical filtration. 

To 3 mL of immune and preimmune antisera of immunized and non-immunized New Zealand white rabbits, respectively, add a saturated solution of ammonium sulfate dropwise at 4°C to obtain a 45% saturated solution. Separate the supernatant after 4h from the solid by centrifugation (4000 x g, 10 min). Dissolve the solid in 1.5 mL of PBS and dialyze against PBS 0.5 mM (4 x 5 L) and Milli-Q water (1 x 5 L) at 6°C. Filtrate a solution of the antibodies in PBS 20 mM by passing them through a 0.45 pm filter and purify with a HiTrap Protein A HP column. Finally, dialyze and lyophilize the antibodies as above described. 10 mg of pure antibody is obtained. 

The filtrate containing the sodium ferrate is transferred to a 250-ml. beaker, which is put in a water bath at 20°, and 100 ml. of saturated potassium hydroxide solution is added with stirring. Stirring is continued for 5 minutes, after which the suspension is filtered through a fritted-glass filter of medium porosity and large surface area (centrifugation may be substituted for filtration here).f The filtrate is discarded. 

SOLUBILITY OF PRECIPITATES A large number of reactions employed in qualitative inorganic analysis involve the formation of precipitates. A precipitate is a substance which separates as a solid phase out of the solution. The precipitate may be crystalline or colloidal, and can be removed from the solution by filtration or by centrifuging. A precipitate is formed if the solution becomes oversaturated with the particular substance. The solubility (5) of a precipitate is by definition equal to the molar concentration of the saturated solution. Solubility depends on various circumstances, like temperature, pressure, concentration of other materials in the solution, and on the composition of the solvent. 

Purification of Monoclonal Antibody. Immunoglobulins were precipitated from the pooled ascites by addition of an equal volume of saturated ammonium sulfate [50% (NH4)2S04]. The precipitate was collected by centrifugation (20 min 10,240 X g), dissolved in 0.01 M sodium phosphate (pH 6.8), and reprecipitated. After the second ammonium sulfate precipitation, the pellet was dissolved in a minimum volume of 0.01 M sodium phosphate (pH 6.8) and centrifuged for 10 min at 10,600 X g). The resulting supemate was applied to a P6G, gel filtration polyacrylamid, column (Bio-gel Biorad, Rockville Center, NY 1.5 X 40 cm). Fractions containing protein were pooled and applied to a hydroxyapatite column that had been equilibrated with 0.01 M sodium phosphate (pH 6.8). Proteins were eluted with a linear gradient of 0.01 to 0.3 M sodium phosphate. 

---