Dialyzer, preparation

Before assaying the activity, C2 toxin must be trypsinized (Ohishi et ai, 1980 Ohishi, 1987). To prepare the activated toxin, incubate the dialyzed preparation with trypsin at a final concentration of 200 ng/ml in 50 mM PB, pH 8.0, for 30 min at 37 °C. Terminate the trypsinization by adding twice the weight of soybean trypsin inhibitor into the reaction mixture. 

Hyaluronidase has an absolute requirement for cations, as dialyzed preparations show no activity toward dialyzed substrates. K+, Na+, Ca2+, Mg2+, and Mn2+ all have stimulating properties toward hyaluronidase. The monovalent cations show the strongest stimulating effects and act over a broader range of concentration than divalent cations [50]. Testicular, serum, and lysosomal hyaluronidase seem to have different sensitivities toward NaCl [54,61]. A noncompetitive mechanism was proposed to explain the activation of hyaluronidase by Na+ [59,62]. 

Dialyzed preparation In 0.02M Trls, pH 9.0, eluted from a DEAE-Sephadex G25 column with a linear gradient of 0.05-0.5M KCl In 0.02M Trls, pH 9,0 15 18... 

Gralen (59) has used the ultracentrifuge to study the molecular weight of globin obtained from horse hemoglobin by splitting off the hemes with the acid acetone technique of Anson and Mirsky. Neutralized and dialyzed preparations of the globin were not entirely monodisperse, but the main component was characterized by ... 

Fig. 4. Schematic of a hemodialyzer. The design of a dialyzer is close to that of a sheU and tube heat exchanger. Blood enters through an inlet manifold, is distributed to a parallel bundle of fibers, and exits into a coUection manifold. Dialysate flows countercurrent in an external chamber the blood and dialysate are separated from the fibers by a polyurethane potting material. Housings are typically prepared from acrylate or polycarbonate. Production volume is...

Each interferon preparation was ultracentrifuged at 20,000 revolutions per minute for one hour to remove tissue debris and inactivated virus. The supernatant was dialyzed against distilled water (1 400) for 24 hours at4°C. The material was then freeze-dried. The dried product was reconstituted in one-tenth of the original volume in distilled water and dispensed into ampoules. Reconstituted solutions were assayed for interferon activity, examined for toxicity, and tested for sterility. 

Purification of photoprotein. The dialyzed photoprotein solution was centrifuged to remove precipitates, and then subjected to fractional precipitation by ammonium sulfate, taking a fraction precipitated between 30% and 50% saturation. The protein precipitate was dissolved in 50 ml of 10 mM sodium phosphate, pH 6.0, containing 0.1 mM oxine ( pH 6.0 buffer ), dialyzed against the same buffer, and the dialyzed solution was adsorbed on a column of DEAE-cellulose (2.5 x 13 cm) prepared with the pH 6.0 buffer. The elution was done by a stepwise increase of NaCl concentration. The photoprotein was eluted at 0.2-0.25 M NaCl and a cloudy substance (cofactor 1) was eluted at about 0.5 M NaCl. The photoprotein fraction was further purified on a column of Sephadex G-200 or Ultrogel AcA 34 (1.6 x 80 cm) using the pH 6.0 buffer that contained 0.5 M NaCl. 

The solution is dialyzed against the same buffer using a hollow fiber assembly, and then added onto a column of Affi-Gel Blue (50-100 mesh, 2 x 15 cm, Bio-Rad) prepared with the same buffer. The column is washed with the same buffer. Then luciferase is eluted with 50 mM Tris-HCl, pH 8.5, containing 5mM EDTA, 3 mM DTT, and 0.5 M NaCl (Hastings and Dunlap, 1986, state that it may be preferable to omit the Affi-Gel step because of difficulties encountered). 

The permeability tests for alkali metal ions in the aqueous solution were also conducted. When an aqueous salt solution moves to cell 2 through the membrane from cell 1, the apparent diffusion coefficient of the salt D can be deduced from a relationship among the cell volumes Vj and V2, the solution concentration cx and c2, the thickness of membrane, and time t6 . In Table 12, permeabilities of potassium chloride and sodium chloride through the 67 membrane prepared by the casting polymerization technique from the monomer solution in THF or DMSO are compared with each other and with that the permeability through Visking dialyzer tubing. The... 

To prepare the mild-alkali-extract, dry watermelon cell walls were suspended in a solution of 0.1 N NaOH, and allowed to react with stirring at room temperature for 15 minutes. A pH of 13, as indicated by pH paper, was kept constant during this period by addition of 0.1 N NaOH. To ensure complete reaction, the treatment was continued overnight at 4 °C. The soluble portion was separated by centrifugation at 10,000 RPM for 20 minutes in a Sorval GSA rotor. The insoluble portion was washed twice with water. The supernatants were combined and, after neutralization to pH 7.0 with acetic acid, dialyzed against distilled water and freeze dried. 

Preparation of enzyme. Culture fluids of three days on glucose 0.5% (w/v) and then four days on pectin 0.5% (w/v), cleared by passing through glass fibre filter, were used for the purification of PNL. A small quantity was remainder, dialyzed, and assayed for enzyme actitity and the remained was precipitated. 

Hydrolytic stability studies were performed by preparing one wt.-% aqueous solutions in culture tubes, adjusting the solutions to the desired pH and placing the sealed tubes in an oven at the desired temperature. The tubes were removed at various times, cooled to roam temperature, dialyzed and freeze-dried. 

Dialyze the phycobiliprotein into 50mM sodium borate, 0.3M NaCl, pH 8.5 (Note Commercial preparations of these proteins come as an ammonium sulfate suspension). 

Polystyrene latices used as an adsorbent were prepared by the Kotera-Furusawa-Takeda method(8 to reduce the spurious effects of surface active substances. The average diameter(D) and the surface gharge density(ao) of the latex particles were determined D=2000 A and 0O = 1.5 uC/cm. A silica sample was prepared by the method described by Stttber et al.(9), and was composed of highly mono-disperse spherical particles of 1900 X in diameter. These colloids were used after dialyzing exhaustively against distilled water to remove the ionic impurities. 

As stressed by Herman-Boussier (H5), the Hp may rapidly lose its HbBC during the isolation procedure, even at neutral pH. She claims that her aqueous, nonsaline Hp solutions, especially of type 2-2, rapidly lose their HbBC which can, however, be preserved for months in the presence of (NH4)2S04 (0.4 M) or in KHCOs (0.02 M). This contrasts with our pure preparation, which can be dialyzed against distilled water without loss of HbBC. This difference in stability of the purified Hp is... 

On the other hand, marked inactivation of the amylase (86 to 87 %) occurred when solutions of the same purified pancreatic amylase preparations were dialyzed under the same conditions but in the absence of substrate.41 These results give experimental evidence for the suggestion often advanced that the amylase unites with its substrate, in this case with the larger less readily dialyzable products of the hydrolysis of starch, and thus is protected from appreciable inactivation due to dialysis. 

Micelle solutions of PlPAAm-Ci8H35 was prepared by direct dissolution of the polymer in cold water (4°C) due to its good water solubility [23]. Each solution of PIPAAm-PSt, PlPAAm-PBMA, and PIPAAm-PLA was prepared by dissolving each copolymer in DMF, A-ethylacetamide, and DMAc, respectively. The solutions were put into a dialysis bag (MWCO = 13,000) and dialyzed against distilled water at 10°C, 20°C, and 4°C, respectively, for 24 hours. The micelles were purified with ultrafiltration membrane of 200,000 molecular weight cut off at 4°C. The aqueous solution was lyophilized to leave a white powder of micelles. 

EAAm was synthesized in our laboratory as described previously [24]. Copolymers of DMAEMA and EAAm were prepared by free radical polymerization as follows 7.8 g of distilled monomers (mixtures of DMAEMA and EAAm) and 0.02 g of AIBN as an initiator were dissolved in 100 mL of a (50/50 by volume) water/ethanol mixture. The feed compositions for poly(DMAEMA-co-EAAm) are shown in Table 2. The ampoule containing the solution was sealed by conventional methods and inunersed in a water bath held at 75°C for 15 h. After polymerization, all polymers were dialyzed against distilled-deionized water at 4°C and freeze-dried. 

Prepare an IgG solution of at least 3 mg/mL in sodium borate buffer. If the antibodies have been stored in sodium azide, the azide must be removed prior to conjugation. Dialyze extensively against the borate buffer (see Note 2). 

D-glucosidase preparations were concentrated and dialyzed with an Amicon model DC-2 Hollow Fiber Ultraconcentrator equipped with HlPlO-20 or HlPlOO-20 cartridges. 

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