Azobis hydrochloride

Water-soluble azo compounds include 4,4 -azobis(4-cyanovaleric acid) (29) and the amidinium hydrochlorides (22 and 23). 

MIP films, applied to a QCM transducer, have been employed for chiral recognition of the R- and 5-propranolol enantiomers [107]. MIP films were prepared for that purpose by surface grafted photo-radical polymerization. First, a monolayer of 11-mercaptoundecanoic acid was self-assembled on a gold electrode of the quartz resonator. Then, a 2,2 -azobis(2-amidinopropane) hydrochloride initiator (AAPH), was attached to this monolayer. Subsequently, this surface-modified resonator was immersed in an ACN solution containing the MAA functional monomer, enantiomer template and trimethylolpropane trimethacrylate (TRIM) cross-linker. Next, the solution was irradiated with UV light for photopolymerization. The resulting MIP-coated resonator was used for enantioselective determination of the propranolol enantiomers under the batch [107] conditions and the FIA [107] conditions with an aqueous-ACN mixed solvent solution as the carrier. The MIP-QCM chemosensor was enantioselective to 5-propranolol at concentrations exceeding 0.38 mM [107]. 

Recently, carboxyl- and amino-functionalized polystyrene latex particles were synthesized by the miniemulsion copolymerization of styrene and acrylic acid or 2-aminoethyl methacrylate hydrochloride (AEMH) [70, 71]. The reaction was started by using an oil-soluble initiator, 2,2 -azobis(2-methylbutyronitrile) (V-59). Two types of surfactant, i.e., ionic negatively charged SDS or positively charged CTMA-Cl, and nonionic Lutensol AT50 (which is a PEO hexadecyl ether with an EO block length of about 50 units) were used to stabilize the initial droplets and final particles. 

Measure oxygen consumption during controlled lipid oxidation induced by thermal decomposition of 2,2 Azobis(2-aminopropane) hydrochloride AAPH Based on inhibition of production of 2,2 Azinobis(3-ethylbenzthiazoline)-6-sulfonic acid ABTS radical cation and mM concentration of a Trolox solution having antioxidant capacity equivalent to 1.0-mM solution of test substance... 

Hydroxytyrosol dose dependently (1-10 p,M) prevented peroxyl radiczil dependent oxidation by the water soluble azo compound AAPH, 2,2 -azobis(2-amidinopropane)hydrochloride. At 5 )xM of the anti-oxidant the lag-time before oxidation took place increased to 2 hrs [55]... 

The ability of flavonoids to enhance the resistance to oxidation and to terminate free-radical chain reactions in lipophilic systems can be monitored using low-density lipoproteins (LDL) as a model (Rice-Evans et al., 1996). The LDL oxidation is initiated either by copper or by a peroxyl radical [2,2 azobis(2-amidinopropane hydrochloride) (AAPH)] (Abuja et al., 1998). Hexanal liberated from the decomposition of oxidized n-6 polysaturated fatty acids in LDL may be determined by static headspace gas chromatography (Frankel and Meyer, 1998). Also, bleaching of P-carotene (Velioglu et al., 1998 Fukumoto and Mazza, 2000) and the tracing by HPLC (Fukumoto and Mazza, 2000) of malonaldehyde formed in lipid emulsion systems in the presence of iron (Tsuda et al., 1994) have been used to measure antioxidants in lipophilic systems. 

Olive oil wastewaters are rich in antioxidant compounds, particularly in hydroxytyrosol derivatives (Visioli et al., 1999). Hydroxytyrosol strongly inhibited low-density lipoprotein oxidation stimulated by 2,2 -azobis(2-aminopropane) hydrochloride (Aruoma et al., 1998). Further investigations point out that hydroxytyrosol and oleuropein are potent scavengers of superoxide radicals (Visioli et al, 1998). Tyrosol and hydroxytyrosol are dose-dependently absorbed by humans and eliminated as their glucuronide conjugates, indicating a good bioavailability (Visioli et al., 2000). 

The free radical-scavenging capacity of oleuropein and hydroxy-tyrosol was tested, using some radical generators. As a radical initiator, AAPH 2,2 -azobis (2-amidinopropane)-hydrochloride) was used for peroxyl radicals generation, because it is a common free radical found in the body [59] and has often been used in several antioxidant activity assays [60]. It appears to be slightly less reactive than OH-radical [61]. 

Z-L-Asp(OH) -L-Phe-OMe is available from Indofine Chemical Co. (Somerville, NJ, USA). Z-L-Aspartic acid, Z-D-aspartic acid, L-phenylalanine methyl ester hydrochloride and D-phenylalanine methyl ester hydrochloride are from Sigma (St. Eouis, MO, USA). Acetic anhydride, methacrylic acid, 4-vinylpyridine, and ethylene glycol dimethacrylate are from Merck (Darmstadt, Germany). 2,2 -Azobis(2,4-dimethyl-valeronitrile) is fromWako Pure Chemicals Industries (Osaka, Japan). Anhydrous acetonitrile for polymer preparation is obtained from Eab-Scan (Dublin, Ireland). 

Krainev, A.G. and D.J. Bigelow. Gomparison of 2,2 -Azobis(2-amidinopropane) hydrochloride (AAPH) and 2,2 -Azobis(2,4-dimethylvaleronitrile) (AMVN) as Free-Radical Initiators a Spin-Trapping Study. /. Chem. Soc., Perkin. Trans. 2,... 

Both phosphohpid-containing dehpidated human low-density hpoprotein ghosts and trihnolein-reconstituted low-density hpoprotein were devoid of antioxidants and were extremely susceptible to 2,2 -azobis-(2-amidino propane) hydrochloride-induced oxidation but, paradoxically, were rather resistant to copper-mediated oxidation (Visioli et al. 2000). The dynamic reduction of Cu(II) to Cu(I) was quantitatively decreased in low-density hpoprotein ghosts and in trihnolein-reconstituted low-density Hpoprotein, also lacking the initial rapid reduction and the subsequent inhibition phases, due to the absence of endogenous antioxidants. Conversely, the rate of copper reduction was hnear and hkely due to hpid peroxides, either already present of formed during copper-induced oxidation. 

AAPH, 2, 2 -azobis(2-amidinopropane) hydrochloride, a generator of aqueous peroxyl radicals (Frei et al., 1988, 1989). 

The flavanol catechin prevented plasma lipid peroxidation that was induced by azo compounds such as the water-soluble 2,2-azobis, 2-amidinopropane hydrochloride (AAPH) or the lipid-soluble 2,2-azobis, 2,4-dimethylvaleronitrile... 

Polymerization of vinyl fluoride in an aqueous medium with azobis-(isobutyramidine) hydrochloride and ammonium iodide [256]. 

The inhibitory effect of PG and DG on free radical-induced hemolysis and depletion of intracellular glutathione (GSH) in human erythrocytes has been studied [29]. The mechanism of erythrocyte hemolysis induced by thermolysis of 2,2 -azobis(2-amid-inopropane)hydrochloride (AAPH) has been correlated with lipid peroxidation and oxidation of membrane proteins. This process also provokes the depletion of intracellular GSH. The results obtained showed that PG and DG inhibit hemolysis, the effect being dose dependent. 

Ximenes, V. F., M. G. Lopes, M. S. Petronio, L. O. Regasini, D. FI. S. Silva, and L. M. da Fonseca. 2010. Inhibitory effect of gallic acid and its esters on 2,2 -azobis(2-amidinopropane)hydrochloride (AAPH)-induced hemolysis and depletion of intracellular glutathione in erythrocites. J. Agric. Food Chem. 58 5355-5362. 

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