Browsing by Author "Lopez Alarcon, C."

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    Transdermal penetration of diclofenac in the presence of AAPH-derived peroxyl radicals
    (TAYLOR & FRANCIS LTD, 2009) Rojo Vergara, C.; Lopez Alarcon, C.; Alvarez Figueroa, M. J.
    In vitro transdermal delivery of diclofenac across pig skin in the presence of AAPH-derived peroxyl radicals (2,2'-azo-bis(2-amidinopropane)dihydrochloride) has been studied. The transdermal absorption of diclofenac was estimated using high-performance liquid chromatography after its incubation in vertical cells. The diclofenac transdermal penetration was highly modified by peroxyl radicals. In the presence of AAPH, lower diclofenac absorption was observed. This effect was inhibited by ferulic acid. This could be explained by diclofenac-peroxyl radical interactions. In the pretreatment skin with AAPH, lower diclofenac absorption was higher than control experiments. This behavior should be considered in the topical administration of pharmaceutical preparations containing diclofenac.
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    USE OF THE ORAC-PYROGALLOL RED/ORAC-FLUORESCEIN RATIO TO ASSESS THE QUALITY OF ANTIOXIDANTS IN CHILEAN WINES
    (SOC CHILENA QUIMICA, 2011) Lopez Alarcon, C.; Ortiz, R.; Benavides, J.; Mura, E.; Lissi, E.
    We have recently proposed that ORAC (Oxygen Radical Absorbance Capacity) methods employing fluorescein (ORAC-FL) and pyrogallol red (ORAC-PGR) as target molecules could be considered as complementary indexes. In particular, the ratio ORAC-PGR/ORAC-FL would reflect the average quality of the antioxidants present in a particular sample. In the present work, we evaluated the antioxidant capacity and the total phenol content of twelve Chilean wines (red, rose, and white) employing ORAC and Folin-Ciocalteau methods, respectively. Red wines showed higher Folin and ORAC values than rose and white wines. However, the ORAC-PGR/ORAC-FL ratio of all tested wines was close to 0.5. The results show that it is important to consider both, the phenol content of the sample (measured by ORAC-FL or Folin indexes) and their average reactivity (measured by the ORAC-PGR/ORAC-FL ratio). Both factors are considered relevant in the evaluation of the antioxidant capacity of wines.