Sensitive Electrochemical Sensor Based On an Aminated MIL-101(Cr) MOF for the Detection of Tartrazine

Abstract

The aminated metal–organic framework H 2 N-MIL-101(Cr) was used as the carbon paste electrode (CPE) modifier for the determination of tartrazine (Tz) in soft drinks. The amino material was characterized by electrochemical impedance spectroscopy and showed significantly faster electron transfer with lower charge-transfer resistance (0.13 kΩ) compared to the electrode modified with the unfunctionalized MIL-101(Cr) material (1.1 kΩ). The H 2 N-MIL-101(Cr)-modified CPE [H 2 N-MIL-101(Cr)-CPE] was then characterized by cyclic voltammetry (CV) using [Fe(CN) 6 ] 3– and [Ru(NH 3 ) 6 ] 3+ ions as the redox probes, showing good accumulation of [Fe(CN) 6 ] 3– ions on the electrode surface. A CV scan of Tz in Britton Robinson buffer solution revealed an irreversible system with an oxidation peak at +0.998 V versus Ag/AgCl/KCl. Using CV and differential pulse voltammetry, an electrochemical method for quantifying Tz in aqueous medium was then developed. Several parameters that affect the accumulation and detection steps were optimized. Optimal detection of Tz was achieved after 180 s of accumulation in Britton Robinson buffer solution (pH 2) using 2 mg of H 2 N-MIL-101(Cr) material. Under optimal conditions, the sensor exhibited a linear response in the concentration range of 0.004–0.1 μM and good detection sensitivity (35.4 μA μM –1 ), and the detection limit for Tz was found to be 1.77 nM (S/N = 3). Satisfactory repeatability, stability, and anti-interference performance were also achieved on H 2 N-MIL-101(Cr)-CPE. The sensor was applied to commercial juices, and the results obtained were approximately similar to those given by UV–vis spectrophotometry.

Advances in Metal-Organic Frameworks MIL-101(Cr)

“…Sensors have penetrated into a wide range of fields, such as industrial production [ 181 , 182 , 183 ], environmental protection [ 184 ], bioengineering [ 179 , 185 ], medical diagnosis [ 186 , 187 , 188 , 189 ], marine exploration, and so on. MIL-101(Cr) also had great application value in sensing due to its characteristics [ 190 , 191 ]. Haghighi et al [ 192 ] reported a new quartz gas sensor by using MIL-101(Cr) as a sensing material for the detection of formaldehyde gas in the environment.…”

Modified Electrochemical Sensors for the Detection of Selected Food Azo Dyes: A Review

“…The study encompassed a range of substances, including nutrients such as iron, manganese, copper, zinc, magnesium, calcium, sugar, and vitamins B1, B6, E, and C, which were found in soft drinks depending on their composition. The sports drinks tested contained fiber, proteins, carbohydrates, salts, preserva- [51] Copyright (2022), under the terms of the CC-BY-NC-ND 4.0 license., b) Cu 2 + modified Zr-based metal-organic framework-CTAB-graphene for sensitive electrochemical detection of SY [53] Copyright (2022), with permission from Elsevier and c) Determination of SY and TZ in drinks using screen-printed carbon electrodes modified with reduced graphene oxide and NiBTC frameworks. [54] Copyright (2020), with permission from Elsevier.…”

“…The presence of a large number of multifunctional pores, developed by the organic ligands and metals present, greatly contributes to these benefits. [53][54][55][56][57][58]…”

“…Figure 4. Scheme a) Sensitive electrochemical sensor based on an aminated MIL-101(Cr) MOF for the Detection of TZ[51] Copyright (2022), under the terms of the CC-BY-NC-ND 4.0 license., b) Cu 2 + modified Zr-based metal-organic framework-CTAB-graphene for sensitive electrochemical detection of SY[53] Copyright (2022), with permission from Elsevier and c) Determination of SY and TZ in drinks using screen-printed carbon electrodes modified with reduced graphene oxide and NiBTC frameworks [54]. Copyright (2020), with permission from Elsevier.…”

Cr-MOF-Based Electrochemical Sensor for the Detection of P-Nitrophenol

“…Compared with other traditional techniques, electrochemical sensing methods have the advantages of good selectivity, high sensitivity, simple operation, and fast response time [ 7 , 8 , 9 ]. The detection performance of an electrochemical sensor depends on the chemical properties of the modified materials used in the working electrodes [ 10 , 11 ].…”