Polyacrylamide amino-functionalized

While the equations do not necessarily indicate this, only a small amount of ATP (less than 1/1000 of the amount produced by weight) needs to be added in order to initiate the reaction, as the reaction will be perpetuated by the product ATP. The three enzymes are immobilized to a cross-linked polyacrylamide gel by reaction of their primary amino functions with active esters on the polymer surface. 

Dry strength additives are usually water soluble, hydrophilic natural or synthetic polymers, the commercially most important of which are starch, natural vegetable gums and polyacrylamides. These polymers are often made in cationic form by the introduction of tertiary or quaternary amino groups into the polymer, and are therefore polyelectrolytes. They are thus also able to function to some extent as drainage and retention aids. 

The first task was to design a linker between the primary amine functionality on the resin and the hydrazine function that ultimately binds the macrocyclic aldehyde. As mentioned above, the employed resin (PEGA1900) features a primary amino group at the end of a PEG spacer connected to the polyacrylamide backbone. To assure monofunctionalization, the amino group was monobenzylated, thereby preventing possible proximity problems. Subsequently, the resulting secondary amine was provided with a handle for the introduction of the hydrazine functionality (see Scheme 29). 

Meldal and coworkers developed polyacrylamides cross-linked with poly(ethylene glycol), referred to as PEGA, as supports for solid-phase synthesis and on-bead enzymatic assays [181-183]. Functionalization of the polymer was performed in a similar fashion as in the case of other polyacrylamides, i.e. either by copolymerization with N-acryloylsarcosine ethyl ester followed by aminolysis with ethylenediamine, or by copolymerization with an amino group containing monomer. The monomers used for a high-capacity (0.4-0.8 mmol/g [182]) and a low-capacity (0.2-0.4 mmol/g [181]) PEGA support are sketched in Figure 2.7. 

Molecules of type I are the classical product of reactions between monofunctional reactants. In many cases, they can be considered to be derived from the functionalization of a substrate or, reciprocally, of an amine, in order to attach chemical moieties purposely designed for specific uses, without substantially affecting the essential molecular structure. This is the case, for instance, of the antibiotic substance 494, which assumes hydrophilic properties upon aminomethylation of the pharmacologically active substrate having an amino acidic residue, or of the complexant agent 495,- as well as of the polyacrylamide Mannich base 502. - ... 

Different types of floeculants can be prepared by aminomethylation the amino-methyl derivatives of polyacrylamide represent the most widely adopted class of compounds, which includes high-molecular-weight floeculants (502, 517 in Table 38, 562 in Table 40), and has been widely patented. The large amount of research on these pnxlucts is concerned, in particular, with is(x lcctric points, the content of functionalized co-units, the extent of amido groups hydrolysis, and the use of copolymcrs. -"- Applications of acrylamide copolymers grafted onto starch or other polysaccharides arc also considered. ... 

The above task, once accomplished, allows the researcher to view the sequence of DNA bases (read from the polyacrylamide gel) in terms of a series of consecutive codons (triplets of bases that code for amino acids). The next task is to search for the translation start site and the translation stop site. Once the entire sequence of the polypeptide has been acquired from the DNA sequence, the researcher may compare the amino acid sequence with those of all known proteins. This task, which is performed on the computer, can reveal whether or not the polypeptide being studied is closely related to another, better characterized polypeptide. If a close match is found, the researcher may gain insight into the functions of the gene being sequenced. 

Available from Pharmacia Biotech as Immobiline, these are "derivatives of acrylamide with different dissociation constants. For acidic Immobiline (with pK 3.6 or 4.6), carboxylic acid is chosen as a functional group for the bases, tertiary amino groups are selected. When different pK values of Immobiline are mixed in appropriate proportions, together with acrylamide, bisacrylamide, TEMED, and ammonium persulfate, the buffering groups responsible for ereating the pH gradient become covalently attached to the polyacrylamide base. 

Electrophoresis is an analytical method for identifying amino acids by observing their migration as a function of pH under an applied electric field gradient. The technique is referred to as paper or gel electrophoresis depending on whether the support used is paper or a polyacrylamide gel. In paper electrophoresis, a strip of paper is saturated with a buffer solution and then a solution of unknown amino acids is placed at the center of the paper. Electrodes are connected to the ends of the paper... 

Monomer 3 essentially serves to functionalise the polyacrylamide polymer after liberation of the primary amino group of the P-alanine moiety. The hexamethylenediamine groups serve as spacers in order to spatially separate the reactive groups. Monomer 3 was later on replaced by acryloylsarcosin methylester 4 (Scheme 1.5.5. ), which is chemically closer to the basic monomer, in order to achieve a homogenous distribution of the functional groups. 

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