Acetic acid ch3cooh 0.05 m

Food gelatin (Ge, type B 200/220 g blooms, <10 ppm of sulfur dioxide) was provided by Manuel Riesgo, S.A. (Madrid, Spain), and cellulose acetate (CA, 39.8 wt% of acetyl content, Mn ca. = 30,000 g/mol, DS = 2.45) and chitosan (degree of deacetylation 98%, Mv = 1.61 × 105 g·mol⁻¹) were supplied by Sigma Aldrich (Darmstadt, Germany). Acetone (CH₃)₂CO, Acetic acid CH₃COOH 0.05 M, DPPH (2,2-diphenyl-1-picrylhydrazyl) and gallic acid (C₇H₆O₅) were supplied by Sigma Aldrich (Darmstadt, Germany). The reagents used were all of analytical quality.

Cellulose acetate (CA, 39.8% acetylation, Mv = 30,000 g × mol⁻¹, DS = 2.45) and chitosan (CH, 98% deacetylation, Mv = 1.61 × 105 g × mol⁻¹) were purchased from Sigma Aldrich Chemie GmbH (Riedstrasse 2, Steinheim, Germany). The food gelatin (GE, type B 200/220 g blooms, containing < 10 ppm of SO₂) were provided by Manuel Riesgo, S.A. (Madrid, Spain). Zinc chloride (ZnCl₂), gallic acid (C₇H₆O₅), acetone (CH₃)₂CO, acetic acid CH₃COOH [0.05 M], and DPPH (2,2-diphenyl-1-picrylhydrazyl) were obtained from Sigma Aldrich Chemie GmbH (Riedstrasse 2, Steinheim, Germany). All other reagents and chemicals used in this study were of an analytical quality.