Autographic assay for the rapid detection of antioxidant capacity of liquid and semisolid pharmaceutical formulations using ABTS●+immobilized by gel entrapment

ZAMPINI I.C., ; ORDOÑEZ R.M., ; ISLA M.I.

AAPS PHARMSCITECH

SPRINGER

Lugar: Berlin; Año: 2010 vol. 11 p. 1159 - 1163

1530-9932

An autographic assay suitable for the detection of antioxidant compounds in a complex matrix (liquid and semi-solid pharmaceutical formulations) or in isolated compounds was described. The preformed radical monocation of 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS?+) was generated by oxidation of ABTS with potassium persulfate and reduced in the presence of hydrogendonating antioxidants. For a further comparative estimation of its applicability and sensitivity, different medicinal plant extracts, hydrogels and antioxidant compounds were dot seeded or chromatographed on silica gel (TLC) and revealed with ABTS?+ solution (System I) or ABTS?+ immobilized by gel entrapment (System II). Both systems were effective and able to detect antioxidant activity in a micromolar range in seconds. System II was more sensitive and reproducible than System I. This micromethod is quick, inexpensive, and particularly helpful whether it works with numerous samples or on a small scale