Proteins arginine-Sakaguchi

All other available methods for determining serum total proteins have been discussed above in relation to albumin, and their limitations indicated. All methods suffer from differences in the individual protein s contribution of the parameter being measured. However, the tyrosine (Folin-Ciocalteu) and arginine (Sakaguchi) equivalence methods (S7) and the near-ultraviolet spectrophotometric methods are more severely affected in this respect than other methods, and are therefore unreliable for total serum protein analysis. 

For use, add 270 mL of solution (2) to 30 mL of solution (1). Rosolic acid (indicator). Dissolve 1 g of rosolic acid (Cj,Hj Oj) in 10 mL of ethanol and add 100 mL of distilled water. Sakaguchi Reagent (for the presence of arginine in proteins or peptides). To 10 drops of the saturated protein or peptide solution, add 5 drops of 6 N NaOH followed by 5 drops of 0.05% (mass/mass) ethanolic 1-naphthol solution and 10 drops of... 

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