Study on the stability of adrenaline and on the determination of its acidity constants.
In this work, the results are presented concerning the influence of time on the spectral behaviour of adrenaline (C(9)H(13)NO(3)) (AD) and of the determination of its acidity constants by means of spectrophotometry titrations and point-by-point analysis, using for the latter freshly prepared samples for each analysis at every single pH. As the catecholamines are sensitive to light, all samples were protected against it during the course of the experiments. Each method rendered four acidity constants corresponding each to the four acid protons belonging to the functional groups present in the molecule; for the point-by-point analysis the values found were: log beta(1) = 38.25 +/- 0.21, log beta(2) = 29.65 +/- 0.17, log beta (3) = 21.01 +/- 0.14, log beta(4) = 11.34 +/- 0.071.
Corona-Avendaño
S
S
Departamento de Química, Universidad Autónoma Metropolitana (Iztapalapa), Av. San Rafael Atlixco 186, Col. Vicentina, CP, México 09340, DF, Mexico.
Alarcón-Angeles
G
G
Rojas-Hernández
A
A
Romero-Romo
M A
MA
Ramírez-Silva
M T
MT
D000042:Absorption; D004837:Epinephrine / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D013057:Spectrum Analysis; D013997:Time Factors
D004837:Epinephrine