Determination of Phenolic Acids in Sugarcane Vinasse by HPLC with Pulse Amperometry

Figure 4

Effect of 0.20 mol·L⁻¹ acetate buffer (pH 5.0) concentration on the retention times of a mixture of polyphenols. CA: caffeic acid (3.60 mg·L⁻¹); FA: ferulic acid (3.88 mg·L⁻¹); GA: gallic acid (3.40 mg·L⁻¹); p-COA: p-coumaric acid (3.28 mg·L⁻¹); VA: vanillic acid (3.36 mg·L⁻¹). Conditions: isocratic elution with 0.20 mol·L⁻¹ acetate buffer : ultrapure water as mobile phase; flow rate of 0.8 mL·min⁻¹; detection potential of 0.80 V (versus Pd).