Thermosensitive molecularly imprinted polymer coupled with HPLC for selective enrichment and determination of matrine in traditional Chinese medicine.

In this study, a temperature-sensitive molecularly imprinted polymer was prepared by using the bifunctional monomer with the critical phase transition characteristics. Infrared spectrometry, scanning electron microscopy, and specific surface area testing were used to characterize the polymers. Then, the recognizing properties of the polymers were studied. Based on the prepared smart polymers, an SPE-HPLC analytical method for the determination of quinolizidine alkaloids in the extracts of Sophora flavescens was established and verified. Finally, the smart polymers were applied to the enrichment of quinolizidine alkaloids in plant extracts. By changing the temperature and solvents of the solid phase extraction conditions, the extraction process can increase the concentration of quinolizidine alkaloids by 4.3 to 5.2 folds. The extraction process has mild conditions and less time consumption, avoiding the use of a large number of toxic reagents, which indicate that the extraction process are more efficient and environmentally friendly.

Dispersive clean-up process based on a magnetic graphene oxide nanocomposite for determination of 2-glycerol monopalmitate in olive oil prior to GC-FID and GC-MS analysis.

BACKGROUND: Recently, methods have been developed for the better quality control, fraud detection and analytical investigation of olive oil. Magnetic graphene oxide (GO) material is known for its reusability, high adsorption capability and stability in food sample preparation. Monopalmitine or 2-glycerol monopalmitate (2-GMP) is one of the main parameters in the quality assay and classification of olive oil, which can be classified as extra virgin ≤ 0.9% and olive pomace ≤ 1.2. Hence, newly synthesized magnetic GO (MGO) and commercial silica-gel were used as a dispersive solid-phase clean-up (d-SPE) sorbent to determine 2-GMP value in olive oil samples prior to gas chromatography (GC) analysis. The d-SPE method is validated with olive oil certified reference material (CRM) with respect to silica-gel and a MGO nanocomposite. RESULTS: The developed d-SPE method was applied for various virgin, refined and pomace olive oil samples to determine the value of 2-GMP%. The presence of 2-GMP in the samples was confirmed by GC-mass spectrometry analysis based on silylation derivatives of the analyte. Finally, the d-SPE-MGO method was determined 2-GMP% as 1.9% for pomace olive oil, 0.6% for refined olive oil, 0.4% for virgin olive oil and 3.1% for CRM. The MGO provided satisfactory clean-up recovery (124%) in the acceptable data range for CRM2018, and silica-gel also provided satisfactory recovery (83%) for CRM2018. The proposed method performed with higher sensitivity and efficiency for screening 2-GMP% in olive oil. CONCLUSION: The MGO based d-SPE method was applied for clean-up purposes to determine 2-GMP%. It proved superior via its advantageous features of super quickness, easy isolation with an external magnet and the highly efficient exclusion of all the coexisting interfering peaks conventionally generated with a standard silica-gel material. These methods based on MGO and silica-gel are reflected in the dispersive mode of extraction and can be used as alternatives to conventional methods. Considering the benefits of the consumption of significantly fewer sorbents and less time required regarding the dispersive methods, the methods can be utilized as alternatives in contrast to conventional techniques. © 2021 Society of Chemical Industry.

The pesticide residue analysis in commodities with high content of chlorophyll based on the quick, easy, cheap, effective, rugged, and safe method: A review.

In multiresidue analysis, the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) is one of the most popular techniques routinely used by researchers during pesticide analysis of food and vegetable samples. Originally, the QuEChERS method was developed for analysis of pesticide residues from fruits and vegetables, but rapidly gained popularity in the extraction of analytes from different matrices. This analytical approach shows several advantages over traditional extraction techniques: it requires lower sample and solvent amounts while shortening the time of sample preparation. However, it presents some limitations for complex matrices such as those containing high amounts of chlorophyll. To overcome the problem of strong matrix effect and influence of interferences, different approaches are applied. Most are concerning modifications of the cleanup step, that is, sorbent type and its amount. Optimization of other parameters, such as sample size, hydration level, extraction solvent, and buffering, also has an impact on overall performance. Combining proper sample preparation with modern highly sensitive and selective detection techniques enables receiving desired limits of quantification. This article presents an overview of strategies employed by researchers for analysis of green, high chlorophyll content commodities and results obtained in their studies.

Solid-phase extraction methods for nucleic acid separation. A review.

The separation and purification of biomacromolecules such as nucleic acid is a perpetual topic in separation processes and bioengineering (fine chemicals, biopharmaceutical engineering, diagnostics, and biological characterization). In principle, the solid-phase extraction for nucleic acid exhibits efficient phase separation, low pollution risk, and small sample demand, compared to the conventional liquid-phase extraction. Herein, solid-phase extraction methods are systematically reviewed to outline research progress and explore additional solid-phase sorbents and devices for novel, flexible, and high-efficiency nucleic acid separation processes. The functional materials capture nucleic acid, magnetic and magnetic-free solid-phase extraction methods, separation device design and optimization, and high-throughput automatable applications based on high-performance solid-phase extraction are summarized. Finally, the current challenges and promising topics are discussed.

Fabrication of a Magnetic Fluorinated Covalent Organic Framework for the Selective Capture of Benzoylurea Insecticide Residue in Beverages.

Efficient capture of benzoylurea insecticide (BU) residue in food is a vital procedure for food safe monitoring. Herein, a core-shell structured magnetic fluorinated covalent organic framework with good magnetic responsiveness and abundant fluorine affinity sites was successfully synthesized, suitable for magnetic solid-phase extraction (MSPE) of BUs. Using a room-temperature synthesis strategy, the magnetic fluorinated covalent organic framework was fabricated by in situ polymerization of 1,3,5-tris(4-aminophenyl) triazine (TAPT) and 2,3,5,6-tetrafluoroterephthaldehyde (TFTA) on the surface of carboxylated Fe3O4 nanoparticles. The competitive adsorption experiment and molecular simulation verified that this magnetic fluorinated covalent organic framework possesses favorable adsorption affinity for BUs. This magnetic fluorinated covalent organic framework could be easily regenerated and reused at least eight times with no reduction of enrichment performance. Combining this magnetic fluorinated covalent organic framework-based MSPE with high-performance liquid chromatography-tandem mass spectrometry, a novel sensitive method for the analysis of BUs was developed. In yellow wine and fruit juice samples, good linear correlations were obtained for BUs in the range of 10-2000 and 20-4000 ng·L-1, respectively. The limit of quantitation of the BUs ranged from 1.4 to 13.3 ng·L-1 in the two beverage matrices. Desirable precision was achieved, with intraday and interday relative standard deviations lower than 11%.

Sampling of Volatiles in Closed Systems: A Controlled Comparison of Three Solventless Volatile Collection Methods.

Complex inter-organismal communication among plants, insects, and microbes in natural and agricultural ecological systems is typically governed by emitted and perceived semiochemicals. To understand and ultimately utilize the role of volatile semiochemicals in these interactions, headspace volatiles are routinely collected and analyzed. Numerous collection systems are available (e.g., static or dynamic; adsorption or absorption) where the choice of technique should be dependent upon the plant, insect, or microbial ecological system studied, the information sought, and the limitations of each method. Within these constraints, it remains necessary that each method detects and provides the accurate in situ, or in vitro, volatile profile of the studied system. Herein, we analyzed and compared the pros and cons of three solventless, thermal desorption systems (SPME, Tenax/cold trap, SPDE) using a synthetic standard blend of compounds mimicking a simple natural blend (benzaldehyde, b-caryophyllene, (Z)-3-hexenol, 6-methyl-5-hepten-2-one, and limonene). Direct splitless injection and Super Q collections of the standard blend were used as controls. The results indicated that related qualitative, as well as quantitative differences, could be correlated with adsorbent sampling capacity and structural bias. The results for Tenax/cold trap and SPDE also were affected by sampled headspace volumes. All solventless techniques exhibited high analytical reproducibility, with SPME and SPDE providing ease of use, low cost, and minimal instrument modifications. The more complex Tenax/cold trap technique provided higher collection efficiency. Using these results, we provide guidance for technique selection for chemical communication applications.

Chitosan-Graphene Oxide Composite Membranes for Solid-Phase Extraction of Pesticides.

Solid-phase extraction (SPE) coupled to LC/MS/MS analysis is a valid approach for the determination of organic micropollutants (OMPs) in liquid samples. To remove the greatest number of OMPs from environmental matrices, the development of innovative sorbent materials is crucial. Recently, much attention has been paid to inorganic nanosystems such as graphite-derived materials. Graphene oxide has been employed in water-purification processes, including the removal of several micropollutants such as dyes, flame retardants, or pharmaceutical products. Polysaccharides have also been widely used as convenient media for the dispersion of sorbent materials, thanks to their unique properties such as biodegradability, biocompatibility, nontoxicity, and low cost. In this work, chitosan-graphene oxide (CS_GO) composite membranes containing different amounts of GO were prepared and used as sorbents for the SPE of pesticides. To improve their dimensional stability in aqueous medium, the CS_GO membranes were surface crosslinked with glutaraldehyde. The composite systems were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, swelling degree, contact angle, and mechanical measurements. As the GO content increased, a decrease in surface homogeneity, an improvement of mechanical properties, and a reduction of thermal stability of the CS-based membranes were observed. The increased dimensional stability in water, together with the presence of high GO amounts, made the prepared composite membranes more efficacious than the ones based just on CS in isolating and preconcentrating different hydrophilic/hydrophobic pollutants.

Current Applications of Magnetic Nanomaterials for Extraction of Mycotoxins, Pesticides, and Pharmaceuticals in Food Commodities.

Environmental pollutants, such as mycotoxins, pesticides, and pharmaceuticals, are a group of contaminates that occur naturally, while others are produced from anthropogenic sources. With increased research on the adverse ecological and human health effects of these pollutants, there is an increasing need to regularly monitor their levels in food and the environment in order to ensure food safety and public health. The application of magnetic nanomaterials in the analyses of these pollutants could be promising and offers numerous advantages relative to conventional techniques. Due to their ability for the selective adsorption, and ease of separation as a result of magnetic susceptibility, surface modification, stability, cost-effectiveness, availability, and biodegradability, these unique magnetic nanomaterials exhibit great achievement in the improvement of the extraction of different analytes in food. On the other hand, conventional methods involve longer extraction procedures and utilize large quantities of environmentally unfriendly organic solvents. This review centers its attention on current applications of magnetic nanomaterials and their modifications in the extraction of pollutants in food commodities.

Novel solid-phase extraction filter based on a zirconium meta-organic framework for determination of non-steroidal anti-inflammatory drugs residues.

In this study, a zirconium-based metal-organic framework UiO-66-NH2 modified cotton fiber (CF@UiO-66-NH2) was fabricated for the extraction of five common NSAIDs, namely ketoprofen, naproxen, flurbiprofen, diclofenac sodium, and ibuprofen. UiO-66-NH2 was synthesized and immobilized on the surface of cotton fiber using an environmentally friendly aqueous synthesis method. The prepared CF@UiO-66-NH2 composite of 50 mg was loaded into a 13 mm recessed filter for use as a solid-phase extraction (SPE) adsorbent material. The filter was then used to enrich NSAIDs in fish and shrimp muscle tissues followed by ultra-high performance liquid chromatography (UPLC) detection. Several key parameters were evaluated and optimized, including adsorption flow rate, pH value of sample, desorption flow rate, and the formic acid content of the eluent. Under optimized conditions, linear ranges of ketoprofen, naproxen, flurbiprofen, diclofenac sodium, and ibuprofen were 2.0-300.0 ng/mL, 1.4-280.0 ng/mL, 3.0-400.0 ng/mL, 1.0-500.0 ng/mL, and 14.0-560.0 ng/mL, respectively. The detection limits ranged from 0.12 ng/mL to 3.50 ng/mL with recoveries in the range of 72.95-116.99%, RSDs < 9.90%. The results demonstrated that the homemade filters based on CF@UiO-66-NH2 exhibited good reproducibility, stability and adsorption property for the determination of trace-level NSAIDs in complex matrix.

Recent advances in micro- and nanomaterial-based adsorbents for pipette-tip solid-phase extraction.

There are a lot of review papers of sample pretreatment, but the comprehensive review on pipette-tip solid-phase extraction (PT-SPE) is lacking. This review (133 references) is mainly devoted to the development of different types of micro- and nanosorbent-based PT-SPE, including silica materials, carbon materials, organic polymers, molecularly imprinted polymers, and metal-organic frameworks. Each section mainly introduces and discusses the preparation methods, advantages and limitations of adsorbents, and their applications to environmental, biological, and food samples. This review also demonstrates the advantages of PT-SPE like convenience, speed, less organic solvent, and low cost. Finally, the future application and development trend of PT-SPE are prospected.

High crystalline magnetic covalent organic framework with three-dimensional grapevine structure for ultrasensitive extraction of nitro-polycyclic aromatic hydrocarbons in food and environmental samples.

Developing and establishing an efficient pre-treatment approach for the precise extraction of nitrated-polycyclic aromatic hydrocarbons (N-PAHs) from real-life samples is critical for ensuring their safety. In this study, a novel crystalline magnetic covalent organic framework with a grapevine structure not a single core-shell, Fe3O4@TAPT-DMTA-COF, was fabricated via chemical bonding. Unchanging the reticulated structure and high crystallinity of TAPT-DMTA-COF, the combination made this material possess not only simple operation via magnetic decantation but also remarkable chemical stability. Fe3O4@TAPT-DMTA-COF had a large surface area (1578.45 m2/g), and rich electronegative triazine-groups, which makes it become a superior magnetic enrichment material for trace N-PAHs. For N-PAHs analysis, low limits of detection (LODs) (1.43-17.24 ng/L), excellent relative standard deviations (RSDs ≤ 11.52%), and wide linearity (10-5000 ng/L) were obtained. Real-life applications based on this composite have been successfully explored by capturing the N-PAHs emitted from food and environmental samples.

Development of a surfactant-assisted dispersive solid phase extraction using deep eutectic solvent to extract four tetracycline antibiotics residues in milk samples.

In this study, a new floating dispersive solid phase extraction method based on deep eutectic solvents has been developed in a home-made extraction device for the extraction of four tetracycline antibiotics from milk samples. In this approach, the sorbent (activated carbon) was dispersed in whole parts of solution with the aid of air stream and floated on top of the solution with the aid of the surfactant (lauryl betaine) and air bubbles. After collection of the sorbent, the adsorbed analytes were eluted with tetrabutyl ammonium chloride-propionic acid deep eutectic solvent under sonication. In this method, there was no need of organic dispersive and extraction solvents and the used sorbent was collected on top of the solution and collected without centrifugation. The validation parameters showed that low limits of detection (0.1-0.3 µg/kg) and quantification (0.6-1.0 µg/kg), acceptable enrichment factors (52-60), efficient extraction recoveries (80-91%), and satisfactory relative standard deviations (≤9.8%) were obtained. Eventually, the method was successfully applied on different milk samples and tetracycline was determined in them.

Hydrophilic molecularly imprinted polymers functionalized magnetic carbon nanotubes for selective extraction of cyclic adenosine monophosphate from winter jujube.

In this work, a green strategy was developed to prepare molecularly imprinted polymers functionalized magnetic carbon nanotubes in aqueous phase under mild conditions for cyclic adenosine monophosphate. Thanks to water solubility of chitosan, a natural polysaccharide which is rich in amino and hydroxyl groups, provided the feasibility to synthesize the green molecularly imprinted polymers for water soluble template in aqueous media. Coupled with high-performance liquid chromatography, the method exhibited a short equilibrium time (6 min), high adsorption capacity (22.42 µg/mg), high magnetic susceptibility, and good selectivity to template molecule with the imprinting factor of 2.94. A good linearity in the range of 0.020-3.0 mg/mL for target was obtained with a correlation coefficient of 0.9998. The limit of detection (signal-to-noise ratio = 3) and limit of quantitation (signal-to-noise ratio = 10) of the magnetic solid phase extraction method for cyclic adenosine monophosphate were 5 and 15 ng/mg, respectively. And the practical application of chitosan-based molecularly imprinted polymers as adsorbent to isolate and determine cyclic adenosine monophosphate in real natural samples (winter jujube) was demonstrated.

Hydrophilic carrageenan functionalized magnetic carbon-based framework linked by silane coupling agent for the enrichment of N-glycopeptides from human saliva.

In this work, a magnetic graphene material coated with mesoporous silica was selected as the substrate, 3-glycidoxypropyltrimethoxysilane and polyethyleneimine were sequentially bonded through chemical reactions, and then carrageenan was successfully introduced by electrostatic interaction; finally, hydrophilic nanocomposite material was prepared. Due to the large number of hydrophilic groups, and polyethyleneimine was connected by means of chemical bonds, this material exhibits good hydrophilicity and stability for glycopeptide enrichment. In the actual enrichment process, nanomaterial exhibits high selectivity (1:500), high sensitivity (2 fmol), and good repeatability (five cycles). In addition, the synthesized material also shows a good enrichment effect in the face of actual complex biological samples, which captured 40 N-glycopeptides from human saliva, indicating the application potential for enrichment of N-glycopeptides.

Nanoparticle-based polyacrylonitrile monolithic column for highly efficient micro solid-phase extraction of carotenoids and vitamins in human serum.

In this work, a biocompatible monolithic column based micro-solid-phase extraction (µ-SPE) method was developed for biological fluid analysis. A novel nanoparticle-based polyacrylonitrile monolithic column (C30 NP-PMC) was fabricated by incorporating triacontyl (C30) modified silica nanoparticles (NPs) into the polyacrylonitrile monolithic matrix through thermally induced phase separation. With efficient mass transfer and sorption capacity, C30 NP-PMC exhibited outstanding performance for the extraction of carotenoids and fat-soluble vitamins (FSVs) from human serum samples, superior to commercial C18 cartridges as well as liquid-liquid extraction (LLE) method. Under optimal conditions, the proposed µ-SPE method coupled with high-performance liquid chromatography-diode array detection (HPLC-DAD) achieved satisfactory limits of detection (LODs) (1.5-75.0 ng/mL) and good recoveries (85.0-106.5 %) with relative standard deviations (RSDs) of less than 12.1% by consuming lower sorbent (35.0 mg) and organic solvent (0.8 mL). Successful application of the developed method demonstrated the great potential of such monolithic sorbents for efficient isolation and preconcentration of trace analytes from blood samples.

Development of an analytical method for the quantitative determination of multi-class nutrients in different food matrices by solid-phase extraction and liquid chromatography-tandem mass spectrometry using design of experiments.

A simple and rapid analytical method based on solid-phase extraction (SPE) followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) with the aid of design of experiments (DOE) approach was developed and validated for simultaneous determination of multi-class nutrients (water- and fat-soluble vitamins and flavonoids) in various food matrices (vegetables, fruits, and cereals). The factors affecting the SPE method were optimized using DOE tools. The separation was achieved in 13 min using the C18 column by gradient LC programme. The SPE-LC-MS/MS method was validated in terms of limit of detection (1.29-29.17 ng/g), linearity range (25-1000 ng/g), coefficient of determination (0.993-0.999) and recovery (72.53-104.24%) for multi-class nutrients in different food samples. Inter- and intra-day precision were evaluated and found to be within acceptable range. The developed method finds extensive application in the routine analysis of multi-class nutrients in various food matrices.

Facile extraction and determination of organophosphorus pesticides in vegetables via magnetic functionalized covalent organic framework nanocomposites.

Facile enrichment and determination of trace organophosphorus pesticides (OPPs) in foods has been a constantly pursuing goal in food safety field. Herein, Zr4+-immobilized covalent organic frameworks (Fe3O4@COF@Zr4+) have been first constructed and utilized as the powerful adsorbents for magnetic solid-phase extraction (MSPE) of OPPs. Owing to the π-π stacking interaction, hydrogen bonding and Zr4+-phosphate coordination reaction, the composites exhibited excellent selectivity and superior affinity to OPPs. Under optimized conditions, the proposed MSPE method coupled with GC-FPD showed good linearity (R2 ≥ 0.9990) and yielded low limits of detection (0.7-3.0 µg kg-1) for OPPs. Moreover, the developed method was successfully employed for the quantitation of OPPs in spiked vegetable samples and obtained satisfactory recoveries in the range of 87-121% with the relative standard deviations (RSDs) ≤ 8.9%. These results demonstrated that the prepared nanoparticles hold unique advantages for trace OPPs analysis in foodstuffs.

Development of selective preconcentration/clean-up method for imidazolinone herbicides determination in natural water and rice samples by HPLC-PAD using an imazethapyr imprinted poly(vinylimidazole-TRIM).

The development of a novel molecularly imprinted solid-phase extraction (MISPE) method for simultaneous preconcentration of imazapyr (IMP), imazapic (IMZ) and imazethapyr (IMT) with determination by HPLC-PAD (High performance liquid chromatography - photodiode-array detector) is proposed. The polymer synthesis was performed using imazethapyr as template molecule and 1-vinylimidazole as functional monomer. The method is based on preconcentration of 100.0 mL of sample through 200.0 mg of molecularly imprinted poly(vinylimidazole-TRIM) (MIP-1VN) at pH 4.0, followed by elution with 2.0 mL of MeOH:CH2Cl2:HAc (34:62:4, v/v). The range of analytical curve (0.29-200.0, 0.21-200.0 and 0.15-200.0 µg L-1), limits of detection (0.09, 0.06 and 0.04 µg L-1) and preconcentration factors (92, 96 and 98) determined for the herbicides, IMP, IMZ and IMT, respectively, were greatly superior when compared with those ones obtained with commercial adsorbents. The analytical method was successfully applied to spiked surface water and rice samples with good results of recovery values (86-107%).

Highly sensitive determination of endocrine disrupting chemicals in foodstuffs through magnetic solid-phase extraction followed by high-performance liquid chromatography-tandem mass spectrometry.

BACKGROUND: Endocrine disrupting chemicals (EDCs), proved to be potential carcinogenic threats to human health, have received great concerns in food field. It was essential to develop effective methods to detect EDCs in food samples. The present study proposed an efficient method to determine trace EDCs including estrone (E1), 17ß-estradiol (E2), estriol (E3) and bisphenol A (BPA) based on magnetic solid-phase extraction (MSPE) coupled high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) in meat samples. RESULTS: Fe3 O4 @COF(TpBD)/TiO2 nanocomposites were synthesized via functionalization of magnetic covalent organic frameworks (COFs) with titanium dioxide (TiO2 ) nanoparticles, and used as absorbents of MSPE to enrich EDCs. The efficient EDCs enrichment relies on π-π stacking interaction, hydrogen bonding, and the interaction between titanium ions (IV, Ti4+ ) and hydroxyl groups in EDCs, which improves the selectivity and sensitivity. Under the optimized conditions, target EDCs were rapidly extracted through MSPE with 5 min. Combining Fe3 O4 @COF(TpBD)/TiO2 based MSPE and HPLC-MS/MS to determine EDCs, good linearities were observed with correlation coefficient (R2 ) ≥ 0.9989. The limits of detection (LODs) and limits of quantification (LOQs) were 0.13-0.41 µg kg-1 and 0.66-1.49 µg kg-1 , respectively. Moreover, the proposed method was successfully applied to real samples analysis. CONCLUSIONS: The established MSPE-HPLC-MS/MS method was successfully applied to determine EDCs in meat samples with rapidness, improved selectivity and sensitivity. It shows great prospects for EDCs detection in other complicated matrices. © 2020 Society of Chemical Industry.

Determination of patulin in apple juice by amine-functionalized solid-phase extraction coupled with isotope dilution liquid chromatography tandem mass spectrometry.

BACKGROUND: Patulin is a mycotoxin that mainly contaminates apple juice, which is a typical high sugar matrix. Many different adsorbents have been utilized to develop a sample pretreatment method to minimize the matrix interference from apple juice. RESULTS: A simple and reliable extraction method for the determination of patulin in apple juice has been developed. The sample preparation involves a simple one-step cleanup procedure using amine-functionalized polymeric solid-phase extraction cartridges (Retain AX) that effectively remove interferences and facilitate the quantification. Isotope dilution liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) was employed to minimize the matrix effect and ensure reliable results. The limit of detection was as low as 0.2 µg kg-1 , which was satisfactory with regard to current European, US, and Chinese legislation. Matrix-matched linearity (r2 = 0.9997) was established in the range of 1-400 µg kg-1 . Recovery was performed in samples spiked at three levels, and results were between 97.2% and 100.2%. CONCLUSION: The results indicated that, with one-step cleanup, the matrix effect was negligible and sensitivity was satisfactory. Our work provided a simple and reliable method for patulin detection in apple juice and is also very promising in routine quality control. © 2020 Society of Chemical Industry.