Cellulose dialysis tubing

The first pH sensor was developed at NIH (Bethesda, Maryland) and made use of phenol red as acid-base indicator, covalently bound to polyacrylamide microspheres10 such microspheres are contained inside a cellulose dialysis tubing (internal diameter 0.3 mm) connected to a 250 pm plastic fibre (Figure 2). The probe was inserted into either the tissue or the... 

The semipermeability behavior of a polymer him can be measured by equipment that permits measurements of the diffusion of a small-molecule dye through the membrane. In the phosphazene systems investigated, the rate of diffusion varied with the polymer side group ratio. A typical polymer with roughly 50% of the side groups as methylamino and 50% as trifluoroethoxy showed a faster transmission of dye molecules in water than did standard cellulose dialysis tubing. 

Resuspend the precipitated protein obtained from step 10-31 in a second 10 ml cold water. Remove the undissolved protein by centrifugation and combine this supernatant solution with that obtained in step 10-31. This is supernatant V. Note its volume and remove a 0.5 ml sample for assay purposes. The insoluble protein precipitate may be discarded. 10-33. Cut a convenient length (15 to 18 in.) of cellulose dialysis tubing (jin. diameter). Wet the tubing with distilled water and tie two knots in one end of it, as shown in Figure 10-7. 

In this experiment, we will simply be looking for chiral descrimination in ML binding to DNA. The two enantiomers are designated as A-ML and A-ML in Figure 8.7. After equilibrium, an excess of the enantiomer not preferentially bound (A-ML) to the DNA is found in analysis chamber B, which can be detected by circular dichroism spectroscopy. To carry out this experiment, you will use small volumes 1 ml in each A and B chamber. Bel-Art products (Pequannock, NJ, USA) sells a conveniently small dialysis cell for a price that is reasonable for a small inorganic lab section. Alternatively, SPECTRA/ POR j regenerated cellulose dialysis tubing is commercially available in 6.4 mm diameter. 

Ionic reaction by-products are removed by dialysis. The hydrosol is placed in 2-cm diameter cellulose dialysis tubing [VWR] that has been previously cleaned by dialysis. After addition of the hydrosol, the tubing is tied off at each end and placed in a large bath. The water in this bath is changed until its resistivity reaches that of pure, glass-distilled water (SlO ft —cm). The hydrosol is then freeze-dried to remove water and obtain the final product. 

To demonstrate the size of colloidal particles, we perform a dialysis experiment in which two solutions are separated by a semipermeable membrane. The membrane has pores through which small molecules, but not large molecules and colloids, can diffuse. Cellulose dialysis tubing (such as catalog number 3787 from A. H. Thomas Co.) has 1- to 5-nm pores. 

Cellulose dialysis tubings were from Serva (Heidelberg, Germany). 

Cellulose dialysis tubings were from Serva, (Heidelberg, Germany). Papain crystal suspension, chondroitinase ABC and heparin lyases were achieved from Sigma (Munich, Germany). 

Dialysis tubing (from Sigma Cat. No. D9652), flat width 33 mm, diameter 21 mm, cellulose (retains > 90% cytochrome c, MM 12.4 kDa, in solution over a 10 h period supplied in rolls, dry may contain glycerol and sulfur compounds in more than trace amounts washing instructions supplied). 

Following the incubation, the remaining octyl glucoside and free, non-incorporated into liposomes mAb 2C5 were removed by dialysis using cellulose ester dialysis tubes with a cutoff size of 300 kDa against 4 L HBS (pH 7.4) for 2 days at 4°C. 

Regenerated cellulose dialysis bags, molecular cut-off 6 8 kDa (e.g., Spectra/Por , Spectrum). Before use, soak the membrane in water for at least 30 min and rinse with distilled water. Standard polypropylene clips (e.g., Spectra/Por Closures, Spectrum) can be employed to seal the tubes. 

Dialysis membranes can be animal membranes and cellophane, but mostly used membranes are made of cellulose. Now, various-sized dialysis tubes, made by the American Union Carbide and American medical spectrum, are commonly used. The MWCO of the tubes are usually around 10,000. In order to improve the efficiency of dialysis, a variety of devices can also be used, including various types of Zeineh dialyzer (Biomed Instruments Inc. US), by which the speed and efficiency of dialysis can be greatly increased. 

While it would be difficult to enumerate all of the efforts in the area of implants where plastics are involved, some of the significant ones are (1) the implanted pacemaker, (2) the surgical prosthesis devices to replace lost limbs, (3) the use of plastic tubing to support damaged blood vessels, and (4) the work with the portable artificial kidney. The kidney application illustrates an area where more than the mechanical characteristics of the plastics are used. The kidney machine consists of large areas of a semi-permeable membrane, a cellulosic material in some machines, where the kidney toxins are removed from the body fluids by dialysis based on the semi-permeable characteristics of the plastic membrane. A number of other plastics are continually under study for use in this area, but the basic unit is a device to circulate the body fluid through the dialysis device to separate toxic substances from the blood. The mechanical aspects of the problem are minor but do involve supports for the large amount of membrane required. 

General Procedure for the Stepwise Hydroformylation/Reductive Amination on Allylated Hyperbranched Polyglycerols (PG). Synthesis of Hydroaminomethylated Hyperbranched PG-dendrimers. PG-Allyl, Rh(acac)(CO)2 and XANTPHOS were dissolved in dry toluene and placed in an autoclave. The autoclave was pressurized with CO/H2 (1 1, 30 bar), heated at 70 °C for 5d. After cooling, the amine was added to the crude PG-aldehyde (1H NMR was used to confirm full conversion) and stirred for 1-2 h. After stirring, Rh(acac)(CO)2 was added and the autoclave was pressurized with CO/H2 (1 6, 70 bar) and heated at 85 °C for 2-5 days. After cooling, the solvent was removed in vacuo and the crude mixture was purified by dialysis (benzoylated cellulose tubing) to give the re-... 

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