Simultaneous spectrophotometric determination of synthetic dyes in food samples after cloud point extraction using multiple response optimizations

Nanoparticle Assisted Fabric Phase Sorptive Extraction for Azo Dye Determination in the Industrial Sewage

Currently, one of the significant environmental problems is the presence of azo dye materials in water sources. In this study, for the first time, a fast and sensitive sample preparation approach using nanoparticle-assisted fabric phase sorptive extraction (NFPSE) followed by high-performance liquid chromatography was examined to remove some azo dyes such as methyl red and sunset yellow from aqueous solutions. Primarily, the significance of several parameters affecting NFPSE, such as fabric type, the kind of sorbent, the number of contacts with sol-gel and the time of contact, was investigated. In addition, experiments were performed to determine the effect of different adsorption parameters, such as sample volume, adsorption time, adsorbent value, desorption time, ionic strength and pH. It was found that the calibration curve was linear within two ranges of concentrations (0.05-0.1 and 0.5-15 ng/L for methyl red; 0.05-0.5 and 0.5-15 ng/L for sunset yellow) with correlation coefficients better than 0.9683. The limit of detection was 0.014 ng/L for methyl red and 0.015 ng/L for sunset yellow. Repeatability Relative Standard Deviation (RSD) with three replicated experiments was 1.5-10% for methyl red and 2.5-5.8% for sunset yellow. Relative recovery percentages of 88-96% for methyl red and 62-92% for sunset yellow were obtained in the samples. Moreover, the results have shown that acceptable accuracy, precision and linearity make the "fabric phase sorptive extraction" a proper method for the determination of dyes from industrial sewage samples.

Spectrophotometric determination for green hydrophobic deep eutectic solvent-based microextraction of Brilliant Blue FCF (E133) from beverages

In this study, a simple, sensitive, and rapid method called green hydrophobic deep eutectic solvent-based liquid-liquid microextraction was developed to extract Brilliant Blue FCF dye from beverages. This method utilizes hydrophobic DES obtained by forming tetrabutylammonium bromide and 1-octanol in a 1:5 ratio as green extraction solvent. The transition of Brilliant Blue FCF to the DES phase occurred on its own, without the need for any reagents such as added salt or tetrahydrofuran. Several crucial factors were tried to get the best extraction efficiency, including species, DES volume and molar ratio, solution pH, ultrasonication, and centrifugation time. Under optimum conditions, extraction recoveries were achieved in the range of 95.1-101.3 % with the method developed for Brilliant Blue FCF. The detection and determination limits were observed to be 4.1 μg l-1 and 12.1 μg l-1, respectively. In addition, the relative standard deviation values for the method's accuracy were found to be 2.23 % and 3.48 % within and between days, respectively. It has been established that the developed method is highly environmentally friendly thanks to the application of the Analytical GREENness (AGREE) and Green Analytical Procedure Index (GAPI) tools. This study shows that DES applications can be carried out without the use of emulsifiers and dispersants by prioritizing the use of hydrophobic DES compounds as environmentally friendly and green extraction solvents in food samples.

Development of a highly sensitive ultra-small ratiometric fluorescence nanosphere probe for Sunset Yellow detection

A highly sensitive ultra-small ratiometric fluorescence nanosphere probe was successfully manufactured to detect Sunset Yellow (SY). The probe, CMCS@N, S-CDs/Rh6G, was formed through the encapsulation of N, S-CDs and Rh6G within carboxymethyl chitosan (CMCS) through in situ cross-linking. Remarkably, our nanosphere probe had an average grain diameter of 6.80 nm and exhibited excellent dispersibility without the need for additional solvents. The probe exhibited a strong linear relationship with SY concentration in the range of 0.26-100 μM, with a low detection limit of 0.078 μM. Furthermore, SY demonstrated strong fluorescence quenching capability on our nanosphere probe, with the fluorescence quenching mechanism involving a combined effects of inner filter effect (IFE) and static quenching. Notably, our nanosphere probe retained the bacteriostatic properties of CMCS, with a substantial bacteriostasis rate of 77.58 %, introducing novel potential applications.

Lab-on kit: A 3D printed portable device for optical and electrochemical dual-mode detection

The hyphenation of electrochemical methods and optical methods in a single portable device is expected to be a challenging combination to enhance the information which can be gained on complex chemical systems. In this paper, a low-cost spectrophotometric device based on low-cost electronics integrated with an electroanalytical cell equipped with a screen printed electrode (SPE) and assembled exploiting a DIY approach, is presented. This easy to use device allowed spectrophotometric and electroanalytical measurements to be performed simultaneously providing simultaneous information and enabling concomitant comparison and autovalidation of the results collected. The analytical robustness and precision of the proposed system was successfully tested on solutions containing mixtures of Patent Blue (E-131) and Brilliant Blue (Erioglaucine E-133), two food dyes displaying optical and redox properties very similar to each other.

Voltammetric Sensor Based on the Combination of Tin and Cerium Dioxide Nanoparticles with Surfactants for Quantification of Sunset Yellow FCF

Sunset Yellow FCF (SY FCF) is one of the widely used synthetic azo dyes in the food industry whose content has to be controlled for safety reasons. Electrochemical sensors are a promising tool for this type of task. A voltammetric sensor based on a combination of tin and cerium dioxide nanoparticles (SnO2-CeO2 NPs) with surfactants has been developed for SY FCF determination. The synergetic effect of both types of NPs has been confirmed. Surfactants of various natures (sodium lauryl sulfate (SLS), Brij® 35, and hexadecylpyridinium bromide (HDPB)) have been tested as dispersive media. The best effects, i.e., the highest oxidation currents of SY FCF, have been observed in the case of HDPB. The sensor demonstrates a 4.5-fold-higher electroactive surface area and a 38-fold-higher electron transfer rate compared to the bare glassy carbon electrode (GCE). The electrooxidation of SY FCF is an irreversible, two-electron, diffusion-driven process involving proton transfer. In differential pulse mode in Britton-Robinson buffer (BRB) pH 2.0, the sensor gives a linear response to SY FCF from 0.010 to 1.0 μM and from 1.0 to 100 μM with an 8.0 nM detection limit. The absence of an interferent effect from other typical food components and colorants has been shown. The sensor has been tested on soft drinks and validated with the standard chromatographic method.

A surfactant-mediated microextraction of synthetic dyes from solid-phase food samples into the primary amine-based supramolecular solvent

An effective and simple surfactant-mediated microextraction of synthetic dyes from solid-phase food samples into the primary amine-based supramolecular solvents is presented for the first time. The developed procedure involved two stages: (i) an isolation of dyes from a solid-phase food sample into a micellar solution of the primary amine; (ii) a preconcentration of the extracted dyes into the supramolecular solvent phase generated from the obtained micellar solution under a coacervation process. The microextraction procedure was applied for the determination of synthetic dyes in confectionery, dried fruits, and spices samples. The supramolecular solvent formed from aqueous micelle aggregates of 1-octylamine due to coacervation induced by thymol provided maximum extraction recovery values for synthetic dyes. In the proposed two-stage extraction procedure the micellar solution of primary amine was a media for analytes isolation from solid-phase and their followed preconcentration.

An Electrochemical Sensor Based on Carbon Paper Modified with Graphite Powder for Sensitive Determination of Sunset Yellow and Tartrazine in Drinks

The paper describes the development of an electrochemical sensor to be used for the determination of synthetic food colorants such as Sunset Yellow FCF (SY) and Tartrazine (TZ). The sensor is a carbon paper (CP) electrode, manufactured by using hot lamination technology and volume modified with fine-grained graphite powder (GrP). The sensor (GrP/CP) was characterized by scanning electron microscopy, energy dispersive spectrometry, electrochemical impedance analysis, cyclic, linear sweep and differential pulse voltammetry. The mechanism of SY and TZ electrochemical oxidation on GrP/CP was studied. The developed sensor has good electron transfer characteristics and low electron resistance, high sensitivity and selectivity. Applying the differential pulse mode, linear dynamic ranges of 0.005–1.0 μM and 0.02–7.5 μM with limits of detection of 0.78 nM and 8.2 nM for SY and TZ, respectively, were obtained. The sensor was used to detect SY and TZ in non-alcoholic and alcoholic drinks. The results obtained from drink analysis prove good reproducibility (RSD ≤ 0.072) and accuracy (recovery 96–104%).

Application of sodium bicarbonate in extraction and determination of synthetic colorant in processed grain products

As the only standard of its kind, GB5009.35-2016 provides the determination of water-soluble synthetic colorants in processed grain products with high starch content for the purpose of food safety risk monitoring. However, it's only applicable to candy products and liquid foods as beverages, but not solid grain products. Extraction is a critical and essential step in the overall analytical process for determination. This paper provides an improved method for extraction of synthetic colorants in food products presenting high starch content. The samples were successively extracted with methanol-water (4:6, v/v) containing 2.7% sodium bicarbonate, and the target analytes were purified by solid phase extraction column. The obtained eluent was concentrated in constant volume, separated by ODS-SP C18 column and determined by diode array detector. The limits of detection were in the range of 2.21 ~ 8.62 ng/mL for 6 synthetic colors. The average recoveries at the spiked levels of 10, 30, 50 μg/kg varied in the range of 79.3 ~ 101.4% with RSD (n = 6) around 0.2 ~ 6.7%. The developed sodium bicarbonate based extraction method was successfully applied to speciation analysis of water soluble azo synthetic colorant in starchy food, such as millet, grits, brown rice, rice flour, cornmeal and cornflakes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-021-05199-x.

An optimization approach for fast, simple and accurate determination of indigo-carmine in food samples

This study report optimization of vortex-assisted natural deep eutectic solvent based liquid-phase microextraction (VA-NADES-LPME) for determination of indigo-carmine in some food samples by UV-Visible spectrophotometer. To ensure efficient extraction, nine different NADES were prepared and tested for the extraction of indigo-carmine. In order to increase extraction efficiency of indigo-carmine, the effects of VA-NADES-LPME variables and their interactions were optimized with central composite design. The optimized method exhibited a linear range between 10 and 900 ng mL^-1. Limit of detection, limit of quantification and enrichment factor were determined as 3.3 ng mL^-1, 10 ng mL^-1 and 135-fold, respectively. The applicability of the optimized method was investigated in selected food samples using the matrix-matching calibration curve. Using optimised experimental conditions (pH of 3.2, 75 µL of NADES-4, 285 µL of THF, and 4 min vortexing), satisfactory recovery results were found in the range of 95.9-104.2% with 1.4-3.7% of relative standard deviation. Finally, the optimized method was economical, simple, green, requires less laborious sampling, and provides superior accuracy and precision in trace-level analysis.

Hydrophobic magnetic nanoparticle assisted catanionic surfactant supramolecular solvent microextraction of multiresidue antibiotics in water samples

A novel extraction technique i.e. hydrophobic magnetic nanoparticle (MNP)-assisted in situ supramolecular solvent (SUPRAS) microextraction was proposed, and it was applied for the analysis of sulfonamides (SAs) and fluoroquinolones (FQs) in aqueous samples, coupled with high performance liquid chromatography-UV detection (HPLC-UV). In this extraction method, hexafluoroisopropanol-mediated salt-free catanionic surfactant based SUPRAS in situ microextraction was initially carried out; then, the SUPRAS was quickly adsorbed by the hydrophobic magnetic nanoparticles and gathered by an external magnetic field. This can greatly shorten the separation time and overcome the dependence on centrifugation, and also perform a secondary extraction of free analytes (not extracted by SUPRAS) from water samples. The magnetic separation ability of different hydrophobic MNPs was evaluated by adsorbing supramolecular aggregates from the water sample. The effective parameters affecting the extraction efficiency of the analytes were investigated and optimized using the one variable at a time method. About 3 min was required to realize the extraction of analytes with an enrichment factor (EF) of 12-53 for SAs and 79-118 for FQs. Compared with the centrifugation-assisted SUPRAS microextraction, the hydrophobic MNP-assisted SUPRAS microextraction obtained much better extraction and preconcentration efficiency. The proposed novel extraction method with HPLC-UV provided LODs of 0.21-0.76 ng mL-1 for SAs and 0.10-0.18 ng mL-1 for FQs. Good linearity was obtained with correlation coefficients ranging from 0.9962 to 0.9999. The intra- and inter-day recoveries of the target antibiotics were in the range of 92.0-111.3% with RSD% below 10.4%. The method was successfully applied to determine SAs and FQs in real water samples, such as lake water, river water, reservoir water, and wastewater.

Doehlert design in the optimization of procedures aiming food analysis - A review

In the present paper is presented a review on the application of Doehlert design in the optimization of some of the steps of analytical procedures aimed the analysis of food samples. The theoretical principles and the main characteristics of this type of design are described. In addition, the main advantages and limitations of Doehlert design over other designs (Central Composite Design and Box-Behnken) and its application in the area of food analysis are discussed. Finally, to illustrate its potential, some examples of Doehlert design application in other areas of food chemistry without the purpose of analytical determination will be briefly presented.

Disposable Electrochemical Sensor for Food Colorants Detection by Reduced Graphene Oxide and Methionine Film Modified Screen Printed Carbon Electrode

A facile synthesis of reduced graphene oxide (rGO) and methionine film modified screen printed carbon electrode (rGO-methionine/SPCE) was proposed as a disposable sensor for determination of food colorants including amaranth, tartrazine, sunset yellow, and carminic acid. The fabrication process can be achieved in only 2 steps including drop-casting of rGO and electropolymerization of poly(L-methionine) film on SPCE. Surface morphology of modified electrode was studied by scanning electron microscopy (SEM). This work showed a successfully developed novel disposable sensor for detection of all 4 dyes as food colorants. The electrochemical behavior of all 4 food colorants were investigated on modified electrodes. The rGO-methionine/SPCE significantly enhanced catalytic activity of all 4 dyes. The pH value and accumulation time were optimized to obtain optimal condition of each colorant. Differential pulse voltammetry (DPV) was used for determination, and two linear detection ranges were observed for each dye. Linear detection ranges were found from 1 to 10 and 10 to 100 µM for amaranth, 1 to 10 and 10 to 85 µM for tartrazine, 1 to 10 and 10 to 50 µM for sunset yellow, and 1 to 20 and 20 to 60 µM for carminic acid. The limit of detection (LOD) was calculated at 57, 41, 48, and 36 nM for amaranth, tartrazine, sunset yellow, and carminic acid, respectively. In addition, the modified sensor also demonstrated high tolerance to interference substances, good repeatability, and high performance for real sample analysis.

Simultaneous Preconcentration and Spectrophotometric Determination of Two Colorants (E110 and E133) in Some Foodstuffs Using a New Mussel-Inspired Adsorbent

BACKGROUND

A naturally occurring material, namely sporopollenin (SP), was subjected to an easy physical surface modification process called a polydopamine coating. The treatment changed the acid-base properties of the surface, so that in the new form the SP surface gained a very attractive character for anionic dyes.

OBJECTIVE

The aim of the study was to develop preconcentration and subsequent spectrophotometric determination methods for two anionic colorants, brilliant blue (BB) and sunset yellow (SY), using polydopamine-coated (PDC) SP.

METHOD

The experiments were carried out in a column system, and the effects of experimental parameters were studied to determine optimal conditions for the quantitative, simultaneous spectrophotometric determination of the dyes.

RESULTS

The dyes could be detected at µg/L levels in their binary mixtures, so the detection limits were found to be 1.5 and 4.3 µg/L in the linear dynamic ranges of 0.0-3.5 and 0-8 µg/mL for BB and SY, respectively. The proposed material and procedure led to quantitative recoveries of between 95 and 100% for the dyes.

CONCLUSIONS

The procedure was applied to real food samples containing BB and SY and both dyes were successfully determined in liquid and solid foodstuffs. The mussel-inspired surface modification is proposed as a useful process to modify the surface of SP.

HIGHLIGHTS

The mussel-inspired polydopamine dip-coating method was adopted to modify the surface of SP for the first time. The PDCSP was successfully used to create a new adsorptive preconcentration method for simultaneous spectrophotometric determination of BB and SY in foodstuffs.

Determination of Sulfonamides in Milk by Cloud Point-Salting Out Extraction and Ultra-High-Performance Liquid Chromatography Tandem Mass Spectrometry

A method involving cloud point-salting out extraction (CPSOE) coupled with UHPLC-MS/MS was developed for the determination of eleven sulfonamides in milk. In this study, the type and concentration of the surfactant, de-emulsification condition, pH value, volume of n-butanol, equilibration temperature and time were optimized. For this developed method, the linear range of SAs was from 0.05 to 50 μg L-1, and the correlation coefficients were higher than 0.997. The average recoveries for SAs were from 61.32 to 91.67%, and the LOQs were less than 0.06 μg kg-1.

Simultaneous Spectrophotometric Determination of Brilliant Blue and Tartrazine in Diverse Sample Matrices after Solid Phase Extraction

Background

Brilliant blue (BB) and tartrazine (TZ) are manufactured from petroleum and its products. These are the most popular consumed food dyes and are widely used in foodstuffs. Therefore, overuse of these dyes in foodstuffs and consumption of excessive amounts of these dyes can lead to health problems in humans.

Objective

The aim of this study was to develop a simple separation and preconcentration method for simultaneous spectrophotometric determination of BB and TZ dyes.

Methods

A column solid-phase separation extraction method combined with UV-Vis spectrophotometry was preferred and developed for single and simultaneous determination of BB and TZ dyes.

Results

The preconcentration factor was obtained as 80. Relative standard deviations were below than 4%. Detection limits of the method were determined as 0.29 and 1.21 µg/L for BB and TZ, respectively. Recovery values were obtained between 95–99% and 96–100% for BB and TZ, respectively. 10.9–235.7 µg/g and 1.7–8.0 µg/mL of BB contents of real samples were determined for solid and liquid samples, respectively. TZ concentrations of solid and liquid samples were ranged between 18.7–220.7 µg/g and 5.9–7.5 µg/mL, respectively.

Conclusions

Quantitative extraction results and satisfactory recovery values showed that method was successful and applicable for determination of BB and TZ concentrations in real pharmaceutical, industrial, and foodstuff samples.

Highlights

The method has exhibited a high preconcentration factor and effective separation against to matrix ions. The method did not need an experienced operator with high operation experience. Elution solvent can be chosen according to the availability of the chemicals in the laboratory and cheapness of the chemicals.

Response Surface Optimization of Cactus Pear (Opuntia ficus-indica) with Lantana camara (L. camara) Fruit Fermentation Process for Quality Wine Production

Fermenting blended fruits has been used to improve fruit wine quality. Cactus pear and Lantana camara fruits have well-known nutritive and health benefits. The purpose of this study was to investigate cactus wine quality improvement by applying response surface optimization method of cactus pear and Lantana camara fruits juice fermentation process. Wine quality responses were optimized at an experimental strategy developed using central composite rotatory design by varying fermentation process variable temperature, inoculum, and Lantana camara fruit juice concentration for six days. The developed fermentation models were significant (p < 0.01) to predict alcohol, total phenol content, and sensory property of the final wine accurately. From the statistics calculations, fermentation temperature of 24.8°C, inoculum concentration 10.16% (v/v), and Lantana camara fruit juice concentration of 10.66% (v/v) were the overall optimum values to produce cactus pear fruit wine with alcohol 9.53 ± 0.84% (v/v), total phenol content 651.6 ± 54 (mg L^-1 equivalent to gallic acid), and sensory value of 8.83 ± 0.29. The Lantana camara fruit juice concentration added had shown significant (p < 0.05) enhancement on total phenol content and sensory values of the final wine. The results can be used for large-scale wine production in order to reduce its postharvest losses.

Synthetic Food Dyes – Some Aspects Of Use And Methods Of Determination

Color is one of the key ingredients for increasing the appetizing of food, so food dyes have become firmly established in food production technologies. However, with the acquisition of toxicity data of synthetic food dyes (SFD), there were restrictions and standards for their content in food have emerged. Numerous papers published in recent years demonstrate the importance of the problem of the use and definition of SFD. The review contains over 180 literary references in the field of usage and methods of determination of synthetic food dyes, among them regulatory documents (regulations), official internet resources of international and Ukrainian organizations, review articles and original works. Varieties of chromatography, enzyme-linked immunoassay, optical and electrochemical methods are used to identify and determine SFD. Special attention was paid to voltammetry (VA) as a method that is cheaper than chromatography and completely satisfies selectivity, sensitivity, reliability requirements and is compatible with the concept of green analytical chemistry, as it doesn't need organic solvents. Moreover, single sweep voltammetry can be considered as a screening method with low limits of determination and rapid respons

Simultaneous biosorption of Arsenic (III) and Arsenic (V): Application of multiple response optimizations

In this work, simultaneous biosorption of As(III) and As(V) by Sargassum glaucescens was optimized using multiple response optimizations and Doehlert experimental design. The optimum condition for simultaneous biosorption of As(III) and As(V) were: biosorbent dosage 0.47 g L-1, pH 5.9 and initial concentration 120.34 mg L-1 with maximum overall desirability of 0.94. Different isotherms were fitted to biosorption equilibrium data and the Freundlich isotherm was the most suitable model. Based on thermodynamic study, the biosorption of arsenic species onto alga was endothermic and spontaneous. Kinetic results indicated that intraparticle diffusion model was the best kinetic model. Biosorption capacity of S. glaucescens and other biosorbents were also compared.

A Comparative Study of Advanced Stationary Phases for Fast Liquid Chromatography Separation of Synthetic Food Colorants

Food analysis demands fast methods for routine control and high throughput of samples. Chromatographic separation enables simultaneous determination of numerous compounds in complex matrices, several approaches increasing separation efficiency and speed of analysis were involved. In this work, modern types of column with monolithic rod or superficially porous particles were employed and compared for determination of eight synthetic food dyes, their chromatographic performance was evaluated. During method optimization, cyano stationary phase Chromolith Performance CN 100 × 4.6 mm and Ascentis Express ES-CN 100 × 4.6 mm, 5 µm were selected for the separation of polar colorants. The separation was performed by gradient elution of acetonitrile/methanol and 2% water solution of ammonium acetate at flow rate 2.0 mL min-1. Mobile phase composition and the gradients were optimized in order to enable efficient separation on both columns. The method using fused-core particle column provided higher separation efficiency, narrow peaks of analytes resulted in increased peak capacity and shortening of analysis time. After the validation, the method was applied for analysis of coloured beers, soft drinks and candies.

Ultrasonically synthesis of Mn- and Cu- @ ZnS-NPs-AC based ultrasound assisted extraction procedure and validation of a spectrophotometric method for a rapid preconcentration of Allura Red AC (E129) in food and water samples

This study is devoted on Allura Red as food colorant preconcentration and determination in beverage, fruit juice and drink water samples is based on usage of Mn- and Cu- @ ZnS-NPs-AC as new sorbent for ultrasound-assisted-dispersive solid-phase microextraction (UA-DSPME) combined with ultraviolet-visible spectrophotometric based method (UV-Vis). Contribution of volume of eluent, pH, sorbent mass and sonication time on response following conduction of 28 experiments were optimized and investigated while their significantly justified according to p-value. Values of "Prob > F" less than 0.0500 is proportional with their significant influence on recovery of analyte. Under the optimum conditions 0.14 mL of THF; pH of 2.5; 8 mg of sorbent and 3 min sonication time guide and help achievement of limit of quantification (LOQ) and limit of detection (LOD) of 6.08 and 20.26 ng mL^-1, respectively. The accuracy of method was validated according to calculation of recovery following spiking 400 and 600 ng mL^-1 to blank solution and recovery as more reliable indication of accuracy 93.41 and 102.17% recoveries with RSD < 3.5%, which demonstrate the successful applicability of present method for real sample analysis. The maximum sorbent capacity was 50.0 mg g^-1 based on Langmuir isotherm as best model with high correlation coefficient. Combination of UA-DSPME and UV-Vis lead to higher sensitivity and lower cost for accurate and repeatable monitoring of Allura Red level in beverage, fruit juice and drink water samples with acceptable recovery and reasonable RSD%.

Highly reproducible and sensitive silver nanorod array for the rapid detection of Allura Red in candy

Allura Red (AR) is a highly stable synthetic red azo dye, which is widely used in the food industry to dye food and increase its attraction to consumers. However, the excessive consumption of AR can result in adverse health effects to humans. Therefore, a highly reproducible silver nanorod (AgNR) array was developed for surface enhanced Raman scattering (SERS) detection of AR in candy. The relative standard deviation (RSD) of AgNR substrate obtained from the same batch and different batches were 5.7% and 11.0%, respectively, demonstrating the high reproducibility. Using these highly reproducible AgNR arrays as the SERS substrates, AR was detected successfully, and its characteristic peaks were assigned by the density function theory (DFT) calculation. The limit of detection (LOD) of AR was determined to be 0.05 mg/L with a wide linear range of 0.8-100 mg/L. Furthermore, the AgNR SERS arrays can detect AR directly in different candy samples within 3 min without any complicated pretreatment. These results suggest the AgNR array can be used for rapid and qualitative SERS detection of AR, holding a great promise for expanding SERS application in food safety control field.