Hydrolysis macromolecules

Allcock, H. R., and Kwon, S., Glyceryl polyphosphazenes Synthesis, properties, and hydrolysis. Macromolecules. 21. 

Hydrolysis of polyacrylamide under basic conditions is guide rapid and can be used to introduce acrylate groups into macromolecules. 

At hydrolysis of polyacrylamide in 10 M NaCl at I00°C, the degree of hydrolysis becomes —95%, but in this case a degradation of the macromolecules is observed. Various modes of hydrolysis of polyacrylamide under basic conditions have been reviewed [2,12]. 

In our previous publication [4] we demonstrated that the ammonium salts of different organic and inorganic acids influence the reactions which are performed at the interaction of pectin with ammonia, as they accelerate the ammonolysis and retard the hydrolysis and degradation of the pectin macromolecules. 

Gao, Y., Katsuraya, K., Kaneko, Y., Mimura, T., Nakashima, H., and Uryu, T., Synthesis, enzymatic hydrolysis, and anti-HIV activity of AZT-spacer-curdlan sulfates, Macromolecules, 32, 8319, 1999. 

Part of this symposium was directed to the synthesis, properties and applications of inorganic and organometallic macromolecules with network structures. The section on organo-oxo macromolecules relevant to sol-gel processing addresses the interesting synthesis and challenging characterization efforts in this area. Brinker (p. 314) outlines the complex chemical and physical factors which affect network formation and structure resulting from the hydrolysis of a tetraalkoxysilane. 

Recently, highly branched macromolecular polyamidoamine dendrimers have been prepared with Co11 bound where the metal ions have additional exchangeable coordination sites.450 These macromolecules show a capacity for catalyzing the hydrolysis of phosphate esters, presumably via intermediate bound phosphoester species. 

Fig. 3.4 Schematic drawings illustrating the nucleation of silica precursor and possible mechanisms of reactions leading to silica formation. (A) The precursor hydrolysis. THEOS nucleates on a polysaccharide macromolecule through hydrogen bonds that are formed with hydroxy groups in the biomacromolecule. Per-...

Dissolve the protein or macromolecule to be thiolated at a concentration of lOmg/ml in 50mM sodium phosphate, 0.15M NaCl, pH 7.2. Other non-amine containing buffers such as borate, HEPES, and bicarbonate also may be used in this reaction. The effective pH for the NHS ester modification reaction is in the range of 7.0-9.0, but environments closer to neutrality will limit ester hydrolysis. 

Algaenans Hydrolysis resistant macromolecules of algal origin. 

Other 4-nitrophenyl esters have also been reported to be substrates of various hydrolases. For example, 4-nitrophenyl hexanoate (7.19) was hydrolyzed by bovine serum albumin [39], The affinity of the substrate for the macromolecule was found to be high (Km/n = 0.040 mM, where n is the number of sites), but the reaction itself was slow ( = 5 10-3 s-1, where k2 is the first-order rate constant of the formation of the phenol product from the enzyme-substrate complex). Another ester, 4-nitrophenyl pivalate (7.20), was hydrolyzed by cytoplasmic aldehyde dehydrogenase at a maximum velocity ca. 1/3 and an affinity ca. 1/20 those of the acetate [40], However, the rate-limiting steps were different for the two substrates, namely acylation of the enzyme for the pivalate, and acyl-enzyme hydrolysis for the acetate (see Chapt. 3). 

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