TY - JOUR
T1 - Analysis of Chlorogenic Acids in Coffee with a Multi-walled Carbon Nanotube Electrode
AU - Takahashi, Shota
AU - Wada, Ryotaro
AU - Muguruma, Hitoshi
AU - Osakabe, Naomi
N1 - Funding Information:
This research was funded by Grant-in-Aide for Scientific Research C 19K05172 of Japan Society for the Promotion Science.
Publisher Copyright:
© 2020, Springer Science+Business Media, LLC, part of Springer Nature.
PY - 2020/4/1
Y1 - 2020/4/1
N2 - An electrochemical analysis using a multi-walled carbon nanotube (MWCNT) electrode is applied to examine chlorogenic acids (3-cafeoylquinic (3CQ), 4-cafeoylquinic (4CQ), 5-cafeoylquinic (5CQ), 3,4-dicafeoylquinic (34dCQ), 3,5-dicafeoylquinic (35dCQ), 4,5-dicafeoylquinic (45dCQ), 3-feruloylquinic (3FQ), 4-feruloylquinic (4FQ), and 5-feruloylquinic (5FQ) acid), which are the main ingredients of coffee polyphenols. The MWCNT electrode shows an excellent performance in the electrochemical quantification of chlorogenic acids. Cyclic voltammetry (CV) of all the chlorogenic acids shows redox peak pairs ranging between + 0.27 and + 0.31 V that are assigned to the redox reaction of the catechol group. Changes in the current due to individual chlorogenic acids at the peak potentials are proportional to their concentrations (3CQ, 4CQ, and 5CQ: linear range 0.4–194 μM, sensitivity 1.8 μA μM−1 cm−2; 34dCQ, 35dCQ, and 45dCQ: linear range 9.5–194 μM, sensitivity 4.3 μA μM−1 cm−2; and 3FQ, 4FQ, and 5FQ: linear range 5–194 μM, sensitivity 0.094 μA μM−1 cm−2). High-performance liquid chromatography (HPLC) analysis of coffee infusions shows that chlorogenic acids are almost entirely composed of 3CQ, 4CQ, and 5CQ. The total amounts of 3CQ, 4CQ, and 5CQ in coffee infusions obtained by HPLC show good agreement with those obtained by CV using the MWCNT electrode. This result indicates that the redox peak current can quantify the total amount of chlorogenic acid in a coffee infusion.
AB - An electrochemical analysis using a multi-walled carbon nanotube (MWCNT) electrode is applied to examine chlorogenic acids (3-cafeoylquinic (3CQ), 4-cafeoylquinic (4CQ), 5-cafeoylquinic (5CQ), 3,4-dicafeoylquinic (34dCQ), 3,5-dicafeoylquinic (35dCQ), 4,5-dicafeoylquinic (45dCQ), 3-feruloylquinic (3FQ), 4-feruloylquinic (4FQ), and 5-feruloylquinic (5FQ) acid), which are the main ingredients of coffee polyphenols. The MWCNT electrode shows an excellent performance in the electrochemical quantification of chlorogenic acids. Cyclic voltammetry (CV) of all the chlorogenic acids shows redox peak pairs ranging between + 0.27 and + 0.31 V that are assigned to the redox reaction of the catechol group. Changes in the current due to individual chlorogenic acids at the peak potentials are proportional to their concentrations (3CQ, 4CQ, and 5CQ: linear range 0.4–194 μM, sensitivity 1.8 μA μM−1 cm−2; 34dCQ, 35dCQ, and 45dCQ: linear range 9.5–194 μM, sensitivity 4.3 μA μM−1 cm−2; and 3FQ, 4FQ, and 5FQ: linear range 5–194 μM, sensitivity 0.094 μA μM−1 cm−2). High-performance liquid chromatography (HPLC) analysis of coffee infusions shows that chlorogenic acids are almost entirely composed of 3CQ, 4CQ, and 5CQ. The total amounts of 3CQ, 4CQ, and 5CQ in coffee infusions obtained by HPLC show good agreement with those obtained by CV using the MWCNT electrode. This result indicates that the redox peak current can quantify the total amount of chlorogenic acid in a coffee infusion.
KW - Caffeoylquinic acid
KW - Chlorogenic acid
KW - Coffee infusion
KW - Cyclic voltammetry
KW - Multi-walled carbon nanotube
KW - Redox reaction
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U2 - 10.1007/s12161-020-01714-6
DO - 10.1007/s12161-020-01714-6
M3 - Article
AN - SCOPUS:85078362254
SN - 1936-9751
VL - 13
SP - 923
EP - 932
JO - Food Analytical Methods
JF - Food Analytical Methods
IS - 4
ER -