A porphyrin-based fluorescence method for zinc determination in commercial propolis extracts without sample pretreatment

MARÍA SUSANA DI NEZIO.; JULIO SANTOS REBOUCAS; MARCELO FABIÁN PISTONESI; VICTOR HUGO E ARAÚJO PINTO; WALLACE DUARTE FRAGOSO; GASTÒN D. PIERINI; MARÍA EUGENIA CENTURIÓN; CLARISSA GOMES DE CARVALHO MAIA

LUMINESCENCE : THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE.

JOHN WILEY & SONS LTD

Lugar: LOndres; Año: 2017 vol. 32 p. 1227 - 1232

1522-7235

AbstractThe quantification of zinc in over‐the?counter drugs as commercial propolis extracts by molecularfluorescence technique using meso‐tetrakis(4‐carboxyphenyl)porphyrin (H2TCPP4) was developedfor the first time. The calibration curve is linear from 6.60 to 100 nmol L−1 of Zn2+. Thedetection and quantification limits were 6.22 nmol L−1 and 19.0 nmol L−1, respectively. The reproducibilityand repeatability calculated as the percentage variation of slopes of seven calibrationcurves were 6.75% and 4.61%, respectively. Commercial propolis extract samples from fourBrazilian states were analyzed and the results (0.329?0.797 mg/100 mL) obtained with thismethod are in good agreement with that obtained with the Atomic Absorption Spectroscopy(AAS) technique. The method is simple, fast, of low cost and allows the analysis of the sampleswithout pretreatment. Moreover the major advantage is that Zn‐porphyrin complex presentsfluorescent characteristic promoting the selectivity and sensitivity of the method.