Wavelength-Shift-Based Colorimetric Sensing for Peroxide Number of Edible Oil Using CsPbBr₃ Perovskite Nanocrystals

Abstract

The peroxide number of edible oil relates to its quality. The classical determination methods for the peroxide number are still unsatisfactory due to their complexity and poor reproducibility in the analytical process and their incapability of field rapid detection. In this study, a novel wavelength-shift-based visual method has been developed for the peroxide number determination of edible oil using halide perovskite nanocrystals (CsPbBr3 NCs). In the analysis, the edible oil sample underwent redox reactions with a part of oleylammonium iodide (OLAM-I) in advance. Then, the halogen exchange occurred between the added CsPbBr3 NCs and the iodide ions from the residual OLAM-I. The resulting wavelength shift of the fluorescence emission reflects the peroxide number in the edible oil sample. Under the ultraviolet light excitation at 365 nm, the apparent color of the photoluminescence could directly be compared with a color chart to determine and qualify the peroxide number. Using the approach, the visual detection of the peroxide number of edible oil samples on site could be realized. The detection process takes only ∼15 min and is convenient and accurate.

It is an All‐Rounder! On the Development of Metal Halide Perovskite‐Based Fluorescent Sensors and Radiation Detectors

“…The peroxide number can be measured by calculating the amount of iodine produced by the reaction of peroxides with iodide ion. [76,104] The CsPbBr 3 NCs can undergo anion exchange reaction with halide ions resulting in fluorescence shifting. The halide ion exchange can be used to detect the peroxide number by measuring the iodide ions in the edible oils.…”

“…The LOD of peroxide was found as 0.139 mg/100 g. The reported LOD in this study was much lower than in many other methods. [76] Recently, Huangfu et al [77] detected the quality of edible oil by estimating the total polar materials in the edible oil. Determination of the quality of edible oil by measuring the total polar materials is a very reliable method.…”

Colorimetric Sensing of Benzoyl Peroxide Based on the Emission Wavelength-Shift of CsPbBr3 Perovskite Nanocrystals

“…The photogenerated electrons and holes of LHPs can not only be separated to produce an electric current, but can also be combined to produce light through radiation. LHPs have the characteristics of narrow emission peak, high color purity, and accurate adjustment of emission wavelength through halogen composition in the whole visible region, which indicates application potential in lighting [3][4][5], optical display [6][7][8], laser [9,10], and optical sensing and detection [11][12][13]. However, the fluorescence quantum yield (PLQY) of the macro-sized LHPs is generally not very high, since (a) LHPs have a low generation energy of ion defects (especially halogen defects) and are prone to produce a large number of ion vacancy defects during crystallization; and (b)…”

“…Recently, as shown in Table S1, there have been several reports on the studies and applications of colorimetric sensing based on the wavelength-shift of the halogen exchange characteristics of CsPbX 3 NCs. Chen et al developed a novel colorimetric sensing approach for the peroxide number determination of edible oil, in which the edible oil sample underwent redox reactions with OLAM-I, and then a halogen exchange occurred between the added CsPbBr 3 NCs and the iodide ions from the residual OLAM-I [11]. A colorimetric sensing approach for the determination of Cl − in sweat by the heterogeneous halide exchange between CsPbBr 3 NCs in n-hexane and Cl − in an aqueous solution has also been presented [23].…”

Sensitive Fluorescent Sensor for Hydrogen Sulfide in Rat Brain Microdialysis via CsPbBr3 Quantum Dots

“…However, the protective layer strategy might affect the dispersion or solubility of perovskite quantum dots in aqueous solution. Because of the instability and insolubility of perovskite quantum dots in aqueous solution, most of the currently reported fluorescent sensors without any modification of perovskite quantum dots are suitable for the detection of targets in nonpolar solvents. − Given the promising application of perovskite quantum dots in a fluorescent sensing platform, it is still necessary to develop some method that can realize the application of perovskite quantum dots in aqueous solution or biological tissue samples without any modification.…”