Electrocomposite Developed with Chitosan and Ionic Liquids Using Screen-Printed Carbon Electrodes Useful to Detect Rutin in Tropical Fruits

Abstract

This work reports the development of a composite of the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BP4) and chitosan (CS) described in previous reports through a new method using cyclic voltammetry with 10 cycles at a scan rate of 50.0 mV s−1. This method is different from usual methods such as casting, deposition, and constant potential, and it allows the development of an electroactive surface toward the oxidation of rutin by stripping voltammetry applied to the detection in tropical fruits such as orange, lemon, and agraz (Vaccinium meridionale Swartz), with results similar to those reported in previous studies. In addition, the surface was characterized by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and Raman spectroscopy. The limit of detection was 0.07 µmol L−1 and the relative standard deviation (RSD) of 10 measurements using the same modified electrode was 0.86%. Moreover, the stability of the sensor was studied for six days using the same modified electrode, where the variation of the signal using a known concentration of rutin (RT) was found to be less than 5.0%. The method was validated using a urine chemistry control spiked with known amounts of RT and possible interference was studied using ten substances including organic and biological compounds, metal ions, and dyes. The results obtained in this study demonstrated that this electrodeveloped composite was sensitive, selective, and stable.

A Simple Electroanalytical Method for Detecting Carminic Acid in Foods through a Glassy Carbon Electrode Modified with Chitosan in the Presence of Allura Red

“…Similar carbon electrodes modified with Cs have been previously used to detect sunset yellow [15] and rutin combined with ionic liquids, [18] and rutin combined with graphene [18] …”

“…This change in surface area is among the possible causes of the increased activity of Cs-modified glassy carbon electrodes. [17] Similar carbon electrodes modified with Cs have been previously used to detect sunset yellow [15] and rutin combined with ionic liquids, [18] and rutin combined with graphene. [18] In this new report, the surface of the active area was calculated with much lower concentrations of Fe 2 + /Fe 3 + (CN) 6 compared to the concentration normally reported between 5.0 and 10.0 mmol/ L. The results are shown in Figure 2.…”