In this study, a smartphone-based quantitative dual detection mode device, integrated with gold nanoparticles (GNPs) and time-resolved fluorescence microspheres (TRFMs) lateral flow immunoassays ...(LFIA) for multiplex mycotoxins in cereals were established. The most frequently used visible light and fluorescence detection modes were integrated in one device. A user-friendly application was self-written to rapidly quantify results. GNPs-LFIA and TRFMs-LFIA were used to detect aflatoxin B1 (AFB1), zearalenone (ZEN), deoxynivalenol (DON), T-2 toxin (T-2), and fumonisin B1 (FB1). The visible limits of detection (vLODs) were 10/2.5/1.0/10/0.5, 2.5/0.5/0.5/2.5/0.5 μg/kg for the two methods, respectively. The quantitative limits of detection (qLODs) were 0.59/0.24/0.32/0.9/0.27, 0.42/0.10/0.05/0.75/0.04 μg/kg, respectively. The recoveries of both LFIAs ranged from 84.0%-110.0%. A parallel analysis in 30 naturally contaminated cereal samples was conducted by liquid chromatography–tandem mass spectrometry (LC-MS/MS), the results showed good consistency, indicating the practical reliability of the established methods. The developed two smartphone-based LFIAs provide a promising technique for multiplex, highly sensitive, and on-site detection of mycotoxins.
•GNP and TRFMs-LFIAs were developed to detect co-contamination of 20 mycotoxins from five classes.•A portable reading platform developed based on smartphone App has the advantage of universal data analysis.•Visible light and fluorescence detection modes are integrated in one device.
Achieving complete information about the chemical composition of complex samples requires the use of multianalytical platforms able to maximize the acquisition of high-quality data for unequivocal ...identification. However, this process requires long analysis times and several instruments. Food analysis is one of the analytical fields where the analysis of very complex samples has a huge impact. One of these complex samples is vermouth, a fortified wine based on the maceration of a large number of herbs, fruits, barks, seeds, and leaves. The application of conventional or even advanced analytical techniques like comprehensive two-dimensional (2D) liquid chromatography (LC × LC) does not provide enough separation power to resolve the complete profile of this sample. In this work, a novel 2DLC strategy called multi-
D LC × LC is developed. This new setup consists of the use of two different columns with different separation properties in the second dimension (
D) that can be selected during the LC × LC analysis accordingly to the chemical nature of the compounds eluted from the first dimension (
D). The vermouth sample was analyzed using a
D-PFP and a combination of HILIC (from 0 to 30 min) and C18 (from 30 to the end) columns in the
D. This setup increased both the peak capacity and the orthogonality of the analysis in comparison to the use of only one of the columns in the
D. Multi-
D LC × LC is presented as an integrated 2DLC tool that maximizes the separation capacity for very complex samples.
•Twelve polycyclic aromatic hydrocarbons were studied.•Appropriate performance characteristics were achieved.•Clean-up stage provided a reduction of 84% in the remaining co-extractives content.•High ...enrichment factor was obtained with limits of detection ≤0.3 µg kg−1.•Plackett–Burman design identified the variables that affect the extraction efficiency.
A sensitive GC–MS method is reported for the determination of twelve polycyclic aromatic hydrocarbons (PAHs) in baby food. The sample preparation involves QuEChERS extraction combined with low-density solvent dispersive liquid–liquid microextraction (LDS-DLLME) and ultra-low temperature (−80 °C). Plackett–Burman screening design was employed to identify the main sample preparation variables that affect the extraction efficiency, such as the volume of toluene used in LDS-DLLME. The suitability of proposed method was verified by analytical selectivity, linearity in solvent and matrix-matched calibration curves and adequate recoveries (72–112%) and precision (RSD values ≤11%), under repeatability and within-laboratory reproducibility conditions. High analytical sensitivity was achieved for the monitoring of PAHs at the strict limit of 1 µg kg−1 fixed by the European Commission for baby foods. The validated method was applied to thirty-two commercial baby food samples, and the investigated PAHs were not detected in any sample.
•Yellow and blue emitting carbon were synthetized in totally green way.•A novel molecular imprinting ratiometric fluorescence sensor was developed.•Mesoporous structure was applied to reduce mass ...transfer resistance.•Point-of-care detection of penicillin G residues in milk.
Instant detection of antibiotic residues in dairy products has been remained a challenge. Current methods require careful samples storage and handling, skilled personnel, and expensive instrumentations. Herein, we report the preparation of a ratiometric fluorescent sensor that contains different colored Carbon dots (CDs) as dual fluorophores, and a mesoporous structured molecularly imprinted polymer as a receptor (B/YCDs@mMIP) for penicillin-G (PNG) detection in milk. Upon PNG addition, only the fluorescence of yellow emissive CDs was quenched due to analyte blockage, while that of the blue emissive CDs stayed almost constant, which led to an obvious change in the fluorescence color from the yellow to blue. A linear response in the range of 1–32 nM with a detection limit of 0.34 nM and excellent recognition specificity for PNG over its analogs were also observed. Comparing our sensor with its counterparts, it exhibited a promising potential in the in-situ PNG detection in milk.
► UHPLC opens new perspectives to determine phenolics in complex food samples. ► Higher resolution, higher efficiency and faster separations are achieved in UHPLC. ► UHPLC–MS allows developing rapid, ...sensitive and selective methods. ► Application of UHPLC–MS to determine phenolics in plant origin foods and feeds.
Phenolic compounds, which are widely distributed in plant-derived foods, recently attracted much attention due to their health benefits, so their determination in food samples is a topic of increasing interest. In the last few years, the development of chromatographic columns packed with sub-2μm particles and the modern high resolution mass spectrometry (MS) have opened up new possibilities for improving the analytical methods for complex sample matrices, such as ingredients, foods and biological samples. In addition, they have emerged as an ideal tool for profiling complex samples due to its speed, efficiency, sensitivity and selectivity. The present review addresses the use of the improved liquid chromatography (LC), ultra-high performance LC (UHPLC), coupled to MS or tandem MS (MS/MS) as the detector system for the determination of phenolic compounds in food samples. Additionally, the different strategies to extract, quantify the phenolic compounds and to reduce the matrix effect (%ME) are also reviewed. Finally, a briefly outline future trends of UHPLC–MS methods is commented.
Recent investigations show that carbon-based and metal-based engineered nanomaterials (ENMs), components of consumer goods and agricultural products, have the potential to build up in sediments and ...biosolid-amended agricultural soils. In addition, reports indicate that both carbon-based and metal-based ENMs affect plants differently at the physiological, biochemical, nutritional, and genetic levels. The toxicity threshold is species-dependent and responses to ENMs are driven by a series of factors including the nanomaterial characteristics and environmental conditions. Effects on the growth, physiological and biochemical traits, production and food quality, among others, have been reported. However, a complete understanding of the dynamics of interactions between plants and ENMs is not clear enough yet. This review presents recent publications on the physiological and biochemical effects that commercial carbon-based and metal-based ENMs have in terrestrial plants. This document focuses on crop plants because of their relevance in human nutrition and health. We have summarized the mechanisms of interaction between plants and ENMs as well as identified gaps in knowledge for future investigations.
•There is lack of consistency in the responses of plants to NPs’ exposure.•Plant responses depend on exposure conditions and NP characteristics.•Most of reports focus on seed germination and plant growth.•Mechanisms of interaction between plants and NPs are not well understood.•Further studies at the transcriptomic and genetic levels are needed.
The use of powerful mass spectrometric detectors in combination with liquid chromatography has played a vital role to solve many problems related to food safety. Since this technique is especially ...well suited for, but not restricted to the analysis of food contaminants within the food safety area, this review is focused on providing an insight into this field. The basic legislation in different parts of the world is discussed with a focus on the situation within the European Union (EU) and why it favors the use of liquid chromatography–mass spectrometry (LC–MS). Main attention in this review is on the achievements that have been possible because of the latest advances and novelties in mass spectrometry and how these progresses have influenced the best control of food allowing an increase in the food safety and quality standards. Emphasis is given to the potential and pitfalls of the different LC–MS approaches as well as in its possibilities to address current hot issues in food safety, such as the development of large-scale multi-residue methods and the identification of non-target and unknown compounds. Last but not least, future perspectives and potential directions are also outlined highlighting prospects and achievements.
Azo dyes as widely applied food colorants are popular for their stability and affordability. On the other hand, many of these dyes can have harmful impacts on living organs, which underscores the ...need to control the content of this group of dyes in food. Among the various analytical approaches for detecting the azo dyes, special attention has been paid to electro-analytical techniques for reasons such as admirable sensitivity, excellent selectivity, reproducibility, miniaturization, green nature, low cost, less time to prepare and detect of specimens and the ability to modify the electrode. Satisfactory results have been obtained so far for carbon-based nanomaterials in the fabrication of electrochemical sensing systems in detecting the levels of these materials in various specimens. The purpose of this review article is to investigate carbon nanomaterial-supported techniques for electrochemical sensing systems on the analysis of azo dyes in food samples in terms of carbon nanomaterials used, like carbon nanotubes (CNT) and graphene (Gr).
Hyperspectral imaging was exploited for its potential in direct and fast determination of Pseudomonas loads in raw chicken breast fillets. A line-scan hyperspectral imaging system (900–1700nm) was ...employed to obtain sample images, which were then further corrected, modified and processed. The prepared images were correlated with the true Pseudomonas counts of these samples using partial least squares (PLS) regression. To enhance model performance, different spectral extraction approaches, spectral preprocessing methods as well as wavelength selection schemes based on genetic algorithm were investigated. The results revealed that extraction of mean spectra is more efficient for representation of sample spectra than computation of median spectra. The best full wavelength model was attained based on spectral images preprocessed with standard normal variate, and the correlation coefficients (R) and root mean squared errors (RMSEs) for the model were above 0.81 and below 0.80log10CFUg−1, respectively. In development of simplified models, wavelengths were selected by using a proposed two-step method based on genetic algorithm. The best model utilized only 14 bands in five segments and produced R and RMSEs of 0.91 and 0.55log10CFUg−1, 0.87 and 0.65log10CFUg−1 as well as 0.88 and 0.64log10CFUg−1 for calibration, cross-validation and prediction, respectively. Moreover, the prediction maps offered a novel way for visualizing the gradient of Pseudomonas loads on meat surface. Hyperspectral imaging is demonstrated to be an effective tool for nondestructive measurement of Pseudomonas in raw chicken breast fillets.
► Hyperspectral imaging was used to detect Pseudomonas loads in chicken fillets. ► Different spectral extraction and preprocessing methods were compared. ► Wavelengths were selected by a proposed scheme based on genetic algorithm. ► PLS models using full and selected wavelengths were established and validated. ► Pseudomonas loads were successfully visualized in prediction maps.
•A 2D Au@Ag nanodot array was constructed at the biphase system for SERS analysis.•The 2D Au@Ag nanodot array can generate vigorous electromagnetic fields.•The assay is capable of measuring ...fungicides in fruit juices with low LOD values.•SERS provides a rapid and sensitive way of detecting contaminants in foods.
The design of a novel and reliable plasmonic platform for detecting multiple chemical contaminants in the complex matrix is an exciting topic in the food industry. Herein, a high-performance surface-enhanced Raman scattering (SERS) two-dimensional (2D) nanodot array was designed through liquid-liquid interfacial self-assembly of the core-shell nanoparticles (Au@Ag NPs) and exploited for assessment of dual-fungicides in pear, apple, and orange juices. The 2D Au@Ag nanodot array delivered good uniformity and reproducibility with the substrate-to-substrate relative standard deviation values of 10.51%. This substrate could be used for detecting thiram and thiabendazole in aqueous solutions with the limit of detection of 0.0011 and 0.051 ppm, respectively. Furthermore, satisfactory recoveries ranging from 76–134% for the juices were obtained, demonstrating that the high-throughput 2D Au@Ag nanodot arrays are promising for their applications as sensitive SERS platforms for monitoring chemical contaminants in food products, especially in the beverage industry.
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