A peroxidase-based method for the determination of dopamine, adrenaline, and alpha-methyldopa in the presence of thyroid hormones in pharmaceutical forms

作者：Poliakov Alexey E^*; Dumshakova Anastasia V; Muginova Svetlana V; Shekhovtsova Tatiana N

来源：Talanta, 2011, 84(3): 710-716.

DOI：10.1016/j.talanta.2011.01.074

• Horseradish and soybean peroxidases
• Catecholamines
• Thyroid hormones
• Pharmaceutical analysis

The analytical properties of two commercial plant peroxidases isolated from horseradish roots and soybean hulls in the catalysis of the transformation of some catecholamines were demonstrated in the absence and presence of thyroid hormones (L-thyroxine and 3,3',5'-iodothyronine). For the first time the reactions of dopamine, adrenaline, and alpha-methyldopa oxidation with H(2)O(2) catalysed by horseradish peroxidase with the addition of L-thyroxine as the amplification agent were studied and proposed as the indicator reactions for the simple and rapid enzymatic determination of the indicated catecholamines in their concentration ranges 0.5-300, 4-300. and 100-400 mu M. respectively. The catalytic activity of the enzyme (characterized by the reaction rate) was controlled spectrophotometrically. The optimum conditions for the indicator reactions were thoroughly characterized. The mechanism of the stimulatory effect of L-thyroxine on the oxidation of the catecholamines was discussed. The developed enzymatic procedures were successfully applied for the determination of dopamine, adrenaline, and alpha-methyldopa in some pharmaceutical forms.

• 出版日期2011-5-15