Acrylamide/bisacrylamide, solution preparation

Buffer system according to Davies and Rosenbaum [178]. This buffer system has been worked out for preparative purposes. 100 ml of acrylamide solution (prepared from 3.67% acrylamide, 5% bisacrylamide, in 0.012 M Tris, 0.013 M cacodylate (pH... 

The gel was prepared by mixing 66 ml of gel buffer (0.01 M Cd(C104)2, 0.01 M sodium polyphosphate, pH 11) 7.4 ml acrylamide solution (44.4 g of acrylamide, 1.2 g of methylene-bisacrylamide in 100 ml water) and 62.4 ml water in round bottom flask and deaerated for 5 min with a water pump. Then 1.2 ml of freshly prepared ammonium persulfate solution (150 mg in 10 ml water) and 0.1 ml of N,N,N, N tetramethylethylenediamine (TEMED) were added and mixed carefully to avoid the introduction of air. Finally, 100 ml of the resulting solution was poured carefully, to minimize the introduction of air, into a 25 mm-diameter tube. The monomer solution was overlayered with water to remove the meniscus and reduce the entry of air. The polymerization was allowed to proceed overnight at room temperature. The resulting gel, having a polymer concentration of 2.5% and a cross-link density of 2.6%, was used in a home made apparatus. ... 

Premixed blends of acrylamide and bisacrylamide prepared with varius ratios of monomers were purchased from Eastman Kodak Chemical Company (Rochester, NY). The 37.5 1 and the 19 1 preparations were used for the study. Gels made from these mixtures will be referred to as 2.6% and 5% cross-linked polyacrylamides, respectively. Five grams of each monomer blend were added to 95-g portions of distilled water. Solution was achieved by mixing for 1 h. To each sample was added 1 ml each of a 1% solution of N, N, N, N -tetramethylethylenediamine (Eastman Chemical Co., New Haven, CT) and a 10% solution of ammonium persulfate (Mallinckrodt Laboratory Chemicals, Phillipsburg, N.1). The solutions were poured into an open polyethylene mold and allowed to cure for 12 h at room temperature. The gels were carefully removed and placed in an excess of distilled sterile water for 48 h. The water was replaced several times during the equilibration period. It was felt that this was sufficient to remove unreacted monomers and impurities. The gels were then cut with a steel-ruled die into circles 40 imn in diameter. 

To resolve folded and unfolded conformations of the 387 nt Tetrahymena ribozyme, we use 8% acrylamide (29 1 mono bisacrylamide) in 34 mMTris, 66 mM Hepes (pH 7.5), 0.1 mM EDTA, and 3 mM MgCl2 (THEM3). Hepes is used instead of borate to maintain the native structure of the ribozyme (Buchmueller and Weeks, 2004 Pyle et ah, 1990), whereas the MgCl2 concentration is chosen to be just sufficient to maintain the RNA in its folded state. Twenty-five milliliters of acrylamide solution per gel is prepared and degassed using RNase-free water. 200 /iL 10% ammonium... 

Another successful example is the separation of a series of steroids listed in Fig. 6.11 using a monolithic capillary column prepared by redox initiated polymerization of a solution of acrylamide 4, methylene bisacrylamide 5, vinylsulfonic acid 12, and dodecyl acrylate 18 in N-methylformamide/TRIS-boric acid buffer (pH 8.2) to which polyethylene glycol) (MW 10,000) was added (overall composition 5% T, 60% C, 10% vinylsulfonic acid, 15% lauryl acrylate, 3% polyethylene glycol)). The capillary tube was first vinylized and its part beyond the detection window was coated with linear polyacrylamide to avoid band broadening. Since laser induced fluorescence was used to decrease the detection limit of the method to about 100 attomoles for neutral steroids, all of the analytes were first tagged with dansylhydrazine. Fig. 6.12 shows an... 

Acrylamide and bisacrylamide may be recrystallised if desired ( 8.2.1.). The stock solution contains 19 g acrylamide and 1 g bisacrylamide in 100 ml water. The stock solution of catalyst contains 6.4 ml of DMAEC (Eastman Kodak) in 100 ml. It is reiterated that not all commercial agarose preparations give satisfactory results, and one of those listed in 8.2 should be used to ensure success. 

This gel is prepared from three stock solutions (A) 25 ml of a 0.08 M buffer solution (the nature and the pH of the buffer depends on the problem being studied and will be discussed later) in twice distilled water containing 0.25 ml of N,N,N, N -tetramethylethylenediamine (TEMED) (B) 3.75 g of acrylamide and 0.5 g of N,N -methylene-bisacrylamide (Bis) in 12.5 ml of water (C) 35 mg of ammonium persulfate in 12.5 ml of water. These solutions are stored in brown glass bottles at +4°C. 

Inverse emulsions were also prepared, and (the otherwise difficult) encapsulation with water-soluble monomers like acrylamide was performed [58]. In a first step, a colloidal dispersion was prepared by dispersing the silica particles in an aqueous solution of acrylamide containing a water-soluble dispersant, a crosslinking agent like Af,Af-methylene bisacrylamide and an initiator. The colloidal system was dispersed in decane containing a suitable surfactant. 

Diketone compounds, like acetylacetone, are known to exist in forms of enol and diketo tautomers (Fig. 60c). [200] A conversion from enol to diketo occurs with UV irradiation. Watanabe et al. [201] prepared a hydrogel of a cantilever shape by two-photon photopolymerizing a comonomer solution containing caryloylacetone, acrylamide, and MlsT-methylene bisacrylamide. They illuminated UV (244 nm) light from one side of the cantilever, which was then deflected due to the photoconversion-induced volume expansion. Compared with the previous two mechanisms, here the tautomerization reaction isn t reversible and needs an aqueous ambient for operation, therefore, the UV irradiation of the cantilever is more like a final step of the prototyping. 

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