Guanidinobutyric acid

The effects on the dynamics of photo-injected electrons where not systematically studied, despite scattered reports on the influence of amines, which induce surface deprotonation, and lower surface charge with a resulting negative shift in band edge position and an increase in the open circuit potential, Voc [103], The opposite effect is induced by Li+ ions, which intercalate in the oxide structure. Guanidinium ions increase Voc when used as counterions in place of Li+. Other adsorbing molecules that influence both Voc and short circuit current are polycar-boxylic acids, phosphonic acids, chenodeoxycholate and 4-guanidinobutyric acid. 

An internal standard should always be used for every analysis carried out. This is an amino acid that is known to be absent from the sample under investigation. For instance in blood plasma analysis either of the non-physio-logical amino acids, nor-leucine or a-amino-/3-guanidinobutyric acid, may be used. This should be added in a known amount to the sample prior to any sample pre-treatment (for example, removal of protein). 

Another pathway of ai nine catabolism, shown particularly to occur in insects, is the deamination of L-aiginine by an L-amino acid oxidase to a-keto-i-guanidinovalerate and the oxidative decarboxylation of this compound to y-guanidinobutyrate 171, 172). The latter compound subsequently has been isolated from the urine of the rat and man 173). 

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