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Rapid and effective analysis of foodborne bacteria is crucial for preventing and controlling bacterial infections. Here, we present the synthesis of a self-reporting molecularly imprinted polymer (MIP) as an inner reference probe (IR), and the in-situ growth of metal-organic frameworks on transition metal carbon nitrides (MOF/Ti 3 C 2 T X -MXene) as a signaling nanoprobe (SP). These advancements are then applied in a ratiometric electrochemical bioassay for Staphylococcus aureus (S. aureus) using a hybrid recognition mechanism. When S. aureus is present, the aptamer-integrated MIP (MIP@Apt) efficiently captures it, followed by binding with SP to form a sandwich structure. This leads to decreased current response of IR (I IR) and increased current intensity of SP (I sp), enabling quantification through utilization of the I SP to I IR ratio. The biosensor shows a wide detection range (10–108 CFU mL−1) and low detection limit of 1.2 CFU mL−1. Its feasibility for testing complex samples indicates the potential application in food analysis. • A self-reporting molecularly imprinted polymer was developed for ratiometric electrochemical detection of bacteria. • In-situ growth of MOF on Ti 3 C 2 T x -MXene was proposed, demonstrating exceptional analytical performance. • This study introduced a novel hybrid recognition mechanism utilizing triple synthetic receptors. • The method successfully demonstrated its detection capability in 1-fold diluted complex matrices. [ABSTRACT FROM AUTHOR]

Trichlorfon (TCF) has the possibility of contaminating agricultural crops and posing some health risks to humans. Herein, an electrochemiluminescence (ECL) sensor based on Fe, Cu dual-atom catalysts (Fe/Cu-N-C DACs) and Au@Luminol was developed for the ultrasensitive detection of TCF. Fe/Cu-N-C with diatomic sites has a very high catalytic activity and can be used as a co-reaction accelerator to activate H 2 O 2 to generate a large number of hydroxyl radicals which triggered a strong cathodic ECL signal of luminol. TCF molecularly imprinted polymer (MIP) was further introduced as a specific recognition element, and the interaction between the template molecule and the functional monomer was verified by molecular docking technique. The developed sensing platform was successfully applied to the ultrasensitive detection of TCF with a linear range from 1.0 pg/mL to 5.0 μg/mL with a low detection limit (0.39 pg/mL). This study broadens the application of DACs in ECL sensing. [Display omitted] • Fe/Cu-N-C dual-atom catalyst was developed as an accelerator for luminol-H 2 O 2 system. • At cathodic conditions Fe/Cu-N-C catalyst activates H 2 O 2 to produce ROS, accelerating luminol ECL emission. • Development of a MIP-ECL sensor for trace trichlorfon detection. • Molecular docking verified interaction on template molecule and functional monomer. [ABSTRACT FROM AUTHOR]

The development of a highly selective and sensitive method for detecting chlortetracycline (CTC) is crucial for safeguarding public health and food safety. Herein, a novel ratiometric fluorescence sensor called SiC@ZIF-8@MIP was constructed to specifically recognize and sensitively detect CTC. The sensor has the advantages of fast response speed (7 min), wide linear range (0.1–18 μg mL−1), and low limit of detection (4.56 ng mL−1). With the addition of CTC, the fluorescence of SiC@ZIF-8@MIP is quenched at 410 nm due to the internal filtration effect (IFE) and a new fluorescence signal is generated at 515 nm by CTC due to the aggregation induced emission effect (AIE). Additionally, for rapid on-site detection of CTC, a smartphone is applied to digitize fluorescence images of SiC@ZIF-8@MIP, helping individuals read and analyze the images. This detection method is a promising strategy for on−site assessments of food safety and public health safety. [Display omitted] • A novel ratiometric fluorescence sensor, SiC@ZIF-8@MIP, was developed. • The dual recognition signals of SiC QDs and MIP were introduced. • Ratiometric fluorescence sensor constructed based on IFE and AIE effects. • Smartphone-based visual detection was a promising analytical approach. • The LOD of SiC@ZIF-8@MIP for CTC was 4.56 ng mL−1 and the detection time was 7 min. [ABSTRACT FROM AUTHOR]

17β-E 2 is used in animal growth regulation and agricultural fertilizer, and even ng L−1 mass concentration levels can show biological effects. In this work, Ag NPs was used as surface-enhanced Raman spectroscopy (SERS) source and WS 2 was synthesized by a simple method to provide a uniform distribution platform for Ag NPs. The MIP was the shell, which can selectively enrich the target molecule, pull the distance between the target molecule and SERS source, and protect Ag NPs. A cyclable SERS substrate with high sensitivity for detecting 17β-E 2 in food was constructed. The optimized WS 2 /Ag@MIP as SERS substrate has the advantages of high Enhanced Factor (EF = 2.78 × 109), low detection limit (LOD = 0. 0958 pM), strong anti-interference ability, and good recycling performance. Moreover, the detection of 17β-E 2 in real samples still has good accuracy. This work provides a new possibility for the trace detection of 17β-E 2 in food. • Sandwich WS 2 /Ag@MIP composite material was prepared for the first time and used as SERS base to achieve sensitive detection of 17β-E 2. • Ag NPs was used as SERS source and WS 2 provided a platform for uniform distribution of Ag NPs. The outermost layer was coated with MIP layer, which realized selective adsorption of 17β-E 2 , shortened the distance between 17β-E 2 and Ag NPs and protected the deterioration of Ag NPs. • WS 2 /Ag@MIP as SERS substrate realized sensitivity detect of 17β-E 2 , EF value was 2.78 × 109, the LOD value was 9.58 × 10−13 M. By elution of target molecules in MIP, the SERS substrate can be recycled. • WS 2 /Ag@MIP as SERS substrate realized the detection of 17β-E 2 in real samples. In the actual spiked sample detection, the recovery of 17β-E 2 in milk samples were 97.38% - 105.46%, and RSDs were 3.96% - 5.04%. [ABSTRACT FROM AUTHOR]

This study utilized computational simulation and surface molecular imprinting technology to develop a magnetic metal-organic framework molecularly imprinted polymer (Fe 3 O 4 @ZIF-8@SMIP) capable of selectively recognizing and detecting multiple fluoroquinolones (FQs). The Fe 3 O 4 @ZIF-8@SMIP material was synthesized using the "common" template-ofloxacin, identified by computational simulation, demonstrating notable adsorption capacity (88.61–212.93 mg g−1) and rapid mass-transfer features (equilibration time: 2–3 min) for all tested FQs, consistent with Langmuir adsorption model. Subsequently, this material was employed as a magnetic solid-phase-extraction adsorbent for adsorption and detection of multiple FQs by combining with high performance liquid chromatography. The developed method exhibited good linearity for various FQs within the concentration range of 0.1–500 μg L−1, with low limit of detection (0.0605–0.1529 μg L−1) and limit of quantitation (0.2017–0.5097 μg L−1). Satisfactory recoveries (88.38–103.44%) were obtained when applied to spiked food samples, demonstrating the substantial potential of this Fe 3 O 4 @ZIF-8@SMIP material for rapid enrichment and identification for multiple FQs residues. [Display omitted] • Computational simulation was exploited to screen optimal template, monomer. • Fe 3 O 4 @ZIF-8@SMIP synthesized by computational simulation and SMIT. • Simpler preparation, superparamagnetic property and lower cost of Fe 3 O 4 @ZIF-8@SMIP. • This material used as adsorbent combined with HPLC for detection of FQs. • The magnetic SPE-HPLC method showed remarkable sensitivity in FQs detection. [ABSTRACT FROM AUTHOR]

Phytoestrogens are non-steroidal estrogens produced from plants that can bind with the human body's estrogenic receptor site and be used as a substitute for maintaining hormonal balance. They are mainly classified as flavonoids, phenolic acids, lignans, stilbenes, and coumestans; some are resocyclic acids of lactones, which are mycotoxins and not natural phytoestrogen. Phytoestrogens have many beneficial medicinal properties, making them an important part of the daily diet. Electrochemical sensors are widely used analytical tools for analysing various pharmaceuticals, chemicals, pollutants and food items. Electrochemical sensors provide an extensive platform for highly sensitive and rapid analysis. Several reviews have been published on the importance of the biological and medicinal properties of phytoestrogens. However, this review provides an overview of recent work performed through electrochemical measurements with electrochemical sensors and biosensors for all the classes of phytoestrogens done so far since 2019. • Phytoestrogens, their classification and sources have been discussed. • Electrochemical sensors for phytoestrogens in food samples and dietary supplements. • First comprehensive review of the electrochemical assay of dietary phytoestrogens. • The advantages of new generation electrochemical sensors for phytoestrogens. • Point-of-care testing for rapid test and home test for phytoestrogens in food samples. [ABSTRACT FROM AUTHOR]

Thiabendazole (TBZ) residues in food pose a serious threat to public health. Herein, an ultrasensitive molecularly imprinted electrochemiluminescence sensor (MIECLS) was developed to detect TBZ, using electron autoregulation in nitrogen-doped graphdiyne‑copper nanowires (NGDY-CuNWs) composite luminophore and cyclic amplification strategy of tin disulfide nanosheets (SnS 2 NSs). NGDY-CuNWs composite luminophores were formed by spontaneous chemisorption to provide electrochemiluminescence signals, and the charge redistribution in it resulted in a built-in potential that improved the electron transfer and redox reaction rate. The cyclic transformation of electron pairs (Sn2+/Sn4+) on SnS 2 NSs catalyzed the generation of sulfate anion radicals to amplify electrochemiluminescence signals. Due to the complementary and synergistic interaction of functional monomers, high affinity imprinted cavities were formed to recognize TBZ. MIECLS had a wide detection range of 1 × 10−9–1 × 10−5 mol L−1 with the limit of detection of 1.69 × 10−10 mol L−1 and had huge application potential to detect pesticide residues. [Display omitted] • NGDY stabilized CuNWs by chemisorption to construct composite luminophore. • The built-in potential drived electron rapid transfer to promote redox reaction. • Cyclic catalytic center of SnS 2 NSs exogenous exciters catalyzed ECL emission. • Dual-monomers MIP provided specific multi-recognition sites to detect TBZ. • The MIECLS had been successfully applied to the detection of real samples. [ABSTRACT FROM AUTHOR]

Developing an efficient method for screening Ochratoxin A (OTA) in agriculture products is vital to ensure food safety and human health. However, the complex food matrix seriously affects the sensitivity and accuracy. To address this issue, we designed a novel molecularly imprinted polymer (MIP) electrochemical sensor based on multiwalled carbon nanotube-modified niobium carbide (Nb 2 C-MWCNTs) with the aid of the density functional theory (DFT). In this design, a glassy carbon electrode (GCE) was first modified by Nb 2 C-MWCNTs heterostructure. Afterward, the MIP layer was prepared, with ortho-toluidine as a functional monomer selected via DFT and OTA acting as a template on the surface of Nb 2 C-MWCNTs/GCE using in-situ electropolymerization. Electrochemical tests and physical characterization revealed that Nb 2 C-MWCNTs improved the sensor's active surface area and electron transmission capacity. Nb 2 C-MWCNTs had a good synergistic effect on MIP, endowing the sensor with high sensitivity and specific recognition of OTA in complex food matrix systems. The MIP sensor showed a wide linear range from 0.04 to 10.0 μM with a limit of detection (LOD) of 3.6 nM. Moreover, it presented good repeatability and stability for its highly antifouling effect on OTA. In real sample analysis, the recoveries, ranging from 89.77% to 103.70%, agreed well with the results obtained by HPLC methods, suggesting the sensor has good accuracy and high potential in practical applications. [Display omitted] • A MIP electrochemical sensor based on Nb2C-MWCNTs was designed for OTA detection • The functional monomer was selected via DFT • Nb2C-MWCNTs shows good electrochemical activity to OTA due to synergistic effect • The MIP sensor shows excellent selectivity and sensitivity in agricultural sample analysis [ABSTRACT FROM AUTHOR]

A molecularly imprinted polymer (MIP) based microfiber differential demodulation sensing system for sodium benzoate (SB) concentration detection is proposed. The specific binding of MIP on the surface of microfibers with SB can lead to changes in local refractive index (RI). RI change induces a drift in the interference wavelength, which can be monitored by the power difference between two fiber Bragg gratings (FBGs). The sensing system can detect SB in the concentration range of 0.1–50 μg/ml, and interference wavelength and FBG power difference sensitivities are 0.55 nm/(μg/ml) and 2.64 dB/(μg/ml) in the low concentration range of 0.1–1 μg/ml, respectively, with a limit of detection (LOD) of 0.1 μg/ml. This microfiber differential demodulation sensing system is not only simple to fabricate, but also simplifies the demodulation equipment to reduce the cost, which providing a simple, reliable and low-cost technique for the quantitative detection of SB concentration in beverages and flavoured foods. • Differential demodulation system combined with molecular imprinting technique. • The sodium benzoate detection range is 0.1–50 μg/ml and detection limit is 0.1 μg/ml. • The sensing system is simple to fabricate, high sensitivity, good stability. • This differential sensing system has a broad prospect in the field of food safety. [ABSTRACT FROM AUTHOR]

Ethyl carbamate (EC) is a carcinogen widely found in the fermentation process of Baijiu. Herein, we construct a molecularly imprinted polymers/MXene/cobalt (II) based zeolitic imidazolate frameworks (MIP/MXene/ZIF-67) nano-enzyme sensor for the detection of EC during Baijiu production. The ZIF-67 is synthesized in situ on the MXene nanosheets to provide a superior catalytic activity to H 2 O 2 and amplify the electrochemical signal. The MIP is prepared by the polymerization reaction to recognize EC. Owing to the interaction between EC and EC-MIP, the interferences are effectively eliminated, greatly improving the accuracy of the expected outcome. This approach attains an ultrasensitive assay of EC ranging from 8.9 μg/L to 44.5 mg/L with detection limit of 0.405 μg/L. The accuracy of this method is confirmed by the recovery experiment with good recoveries from 95.07% to 107.41%. This method is applied in natural EC analyses, and the results are consistent with certified gas chromatograph- mass spectrometer. • The prepared MXene/ZIF-67 shows excellent peroxidase-mimicking activities. • A highly sensitive sensor is prepared by specific combination of EC and EC-MIP. • The sensor shows "on-off" state with the change of EC content. [ABSTRACT FROM AUTHOR]

The residues of erythromycin (ERY) may have negative impacts on the ecological environment, health, and food safety. How to detect ERY effectively and visually is a challenging issue. Herein, we synthesized a molecularly imprinted polymer based nanozymes for selective detection of erythromycin (ERY-MIPNs) at neutral pH, and developed a mobile phone-assisted bicolor colorimetric detection system. This system produced a wide range of color changes from blue to pinkish purple as the ERY concentration increased, making it easy to capture the visualization result. Also, the system showed good sensitivity to ERY ranging from 15 to 135 μM, with a detection limit of 1.78 μM. In addition, the system worked well in the detection of ERY in river water and milk, with the recoveries of 95.57% ∼ 103.20%. These data suggests that this strategy is of considerable potential for practical applications and it provides a new idea for visual detection with portable measurement. [Display omitted] • Nanozyme based molecularly imprinted polymer (MIPNs) can selectively recognize the erythromycin (ERY). • MIPNs for ERY detection was conducted at the neutral pH. • Wide range of color changes from blue to pinkish purple can be easily captured by naked eyes. • The results can be easily quantified with the assistance of mobile phone sensing platform. • MIPNs can measure ERY in the river water and milk. [ABSTRACT FROM AUTHOR]

Bovine serum albumin (BSA) has emerged as a biomarker for mammary gland health and cow quality, being recognized as a significant allergenic protein. In this study, a novel flexible molecular imprinted electrochemical sensor by surface electropolymerization using pyrrole (Py) as functional monomer, which can be better applied to the detection of milk quality marker BSA. Based on computational results, with regard to all polypyrrole (PPy) conformations and amino-acid positions within the protein, the BSA molecule remained firmly embedded into PPy polymers with no biological changes. The molecular imprinted electrochemical sensor displayed a broad linear detection range from 1.0 × 10−4 to 50 ng·mL−1 (R2 = 0.995) with a low detection limit (LOD) of 4.5 × 10−2 pg·mL−1. Additionally, the sensor was highly selective, reproducible, stable and recoverable, suggesting that it might be utilized for the evaluation of milk quality. • Novel electrochemical sensor was employed to detect milk quality markers. • The recognition mechanism of the sensor to the milk quality marker was clarified. • MIP sensor was highly selective, reproducible, stable and recoverable. • Utilized for the evaluation of milk quality and the precise detection of allergens. [ABSTRACT FROM AUTHOR]

Misuse of amide herbicides in the fisheries environment can pose unpredictable harm to aquatic products and ultimately human health. Thus, the development of a real-time, rapid on-site detection method is crucial. This study proposes for the first time, a paper-based visual detection method for amide herbicides in fish serum, by coating the molecularly imprinted polymer layer onto quantum dots, prepared fluorescent sensing materials (QDs@MIPs) for the detection of amide herbicides in aquatic products. These materials specifically cause fluorescence quenching in the presence of amide herbicides resulting in a color change. For practical application, this research designed a rapid test strip based on QDs@MIPs, meanwhile, incorporate a smartphone or a fluorescence spectrophotometer for qualitative and quantitative measurements, the limit of detection ranges of 0.061–0.500 μM. The method can be used for on-site evaluation of aquatic products, providing new technology for monitoring the safety of aquatic products. • The sensing system possessed high sensitivity and rapid detection technology. • Test paper was prepared and could be successfully used for qualitative detection. • Smartphone was suitable for colorimetric sensing as detector. • New on-site inspection and monitoring methods for food safety have been established. [ABSTRACT FROM AUTHOR]

A biosensor was constructed by combining the highly selective molecularly imprinted polymer (MIP) technology with aptamers (Apt) to achieve high selectivity for chloramphenicol (CAP). Furthermore, the MOFs material enriched with Au NPs were prepared, and after the addition of Toluidine bule (TB) and Apt, MOFs@Au@TB@Apt with enhanced signals was formed. Subsequently, a highly uniform 3D SERS substrate was prepared. When CAP was present, it could be captured by the rMIP (CAP was eluted) on the SERS substrate through a covalent bond. Upon adding MOF@Au@TB@Apt, the aptamer recognized CAP, thereby linking MOFs@Au@TB with SiO 2 @AuAg, achieving dual selectivity for the analyte and dual signal enhancement of Raman signal. [Display omitted] • The molecularly imprinted polymer and CAP aptamers both have specific recognition to CAP, which can achieve dual recognition for CAP to improve specificity of the SERS aptasensor. • MOFs@Au@TB as an excellent SERS tag can significantly enhance Raman signals to improve CAP detection sensitivity. • SiO 2 @AuAg nanocentrum was orderly and uniformly assembled on silicon wafers to improve sensitivity and homogeneity. • The molecularly imprinted SERS sensor can achieve detect CAP with a detection limit of 7.59×10−13 mol/L. Chloramphenicol (CAP) residue in food can cause great harm to human health, it is important to develop a rapid and sensitive method to detect CAP. Here, molecularly imprinted polymer (MIP) was combined with metal-organic frameworks@Au (MOFs@Au) collaborative construction surface-enhanced Raman spectroscopy (SERS) based aptasensor for CAP ultrasensitive detection. MOFs@Au first carried the Raman signal molecule toluidine blue (TB) and aptamer to form MOFs@Au@TB@Apt. In addition, rMIP (CAP was removed) was dropped onto the uniform three-dimensional (3D) SERS substrate SiO 2 @AuAg to form SiO 2 @AuAg@rMIP. In the presence of target CAP, it could be specifically captured with rMIP by covalent interaction and was recognised by the aptamer. During this time, SiO 2 @AuAg@rMIP@CAP could selectively connect MOFs@Au@TB@Apt to realise synergistic enhance the Raman signal. Based on this principle, the proposed SERS aptasensor exhibits excellent sensitivity with a detection limit of 7.59×10−13 M for CAP, providing a new strategy for trace detection in food. [ABSTRACT FROM AUTHOR]

[Display omitted] • A biomass magnetic dual-dummy-template molecularly imprinted polymer was proposed. • Tyrosine and tryptophan were used as bio-compatible binary functional monomers. • The synthesis was performed using green strategy. • The material showed outstanding adsorption capability for carbamate and organophosphate. • The method exhibits real application in fruits and vegetables. An eco-friendly biomass waste-derived magnetic material coated with a dual-dummy-template molecularly imprinted polymer was fabricated using aqueous ethanol as a green porogen, lower amounts of toxic compounds as template molecules, and tyrosine and tryptophan as biocompatible binary monomers. The binding characteristics and selectivity of the material toward pesticides were assessed. High adsorption capacities ranging from 150.11 to 509.09 mg g−1 and imprinting factors reaching 2.2 were achieved within just 30 s. The material was applied for extraction of organophosphorus and carbamate pesticides prior to HPLC analysis. Under the optimum conditions, low limits of detection and quantitation were achieved, with ranges of 0.05–1.49 μg/L and 0.18–5.00 μg/L, respectively. The established approach enables efficient analysis of vegetable and fruit samples, yielding satisfactory recoveries ranging between 80 and 110 %. The method showed promise as an analytical method for the sensitive enrichment of pesticide residues in vegetable and fruit samples. [ABSTRACT FROM AUTHOR]

Highlights • MIP sensor was fabricated for selective detection of TBHQ in food samples. • An in situ electrochemical assembly was successfully used to fabricate MIP sensor. • The sensor allows sensitive detection of TBHQ with excellent analytical performance. • The detection results obtained by this method showed good consistency with HPLC. Abstract Developing selective and sensitive methods for tertiary butylhydroquinone (TBHQ) detection is of great significance to ensure the quality and safety of food. Herein, an electrochemical sensor was designed for selective and sensitive detection of TBHQ by integrating molecularly imprinted polymer, noble metal nanoparticles and carbon materials. The electrochemical sensor exhibited excellent performance for sensitive determination of TBHQ. The linear range was 0.5–60 μg mL−1 with a low detection limit of 0.046 μg mL−1. In addition, the results obtained by electrochemical method were well agreement with the detection results obtained by HPLC with good recoveries ranging from 99.4 to 108.5% in spiked edible oil samples. The present study not only has theoretical value to establish new methods for rapid detection of food additives but also has potential application values for monitoring the overuse of TBHQ. [ABSTRACT FROM AUTHOR]

Highlights • A dummy-template MIP capable of recognizing 7 Sudan dyes was synthesized. • The MIP's recognition mechanism was studied by using computation simulation. • A reusable and ultrasensitive CL sensor was prepared on common microtiter plate. • The assay consisted of only one sample loading step prior to data acquisition. Abstract The objective of this study is to report a molecularly imprinted polymer-based chemiluminescence method for determination of Sudan dyes. A dummy-template molecularly imprinted polymer capable of recognizing seven Sudan dyes was first synthesized and its recognition mechanism was studied by using computation simulation method. The polymer was coated in the wells of conventional microplate to prepare a chemiluminescence sensor and the assay process consisted of only one sample-loading step prior to signal acquisition. The optimized sensor was used to determine the seven dyes in egg yolk and the results were confirmed with a high performance liquid chromatography. Results showed that this sensor achieved ultrahigh sensitivity (1.0–5.0 pg/mL), rapid assay process (10 min) and satisfactory recovery (70.5%–92.2%). Furthermore, the sensor could be reused for 5 times. Therefore, this sensor could be used as a useful tool for screening the residues of Sudan dyes in egg. [ABSTRACT FROM AUTHOR]

Highlights • Mebendazole was first used as template to synthesize a MIP for benzimidazoles. • Its recognition mechanism for 8 drugs was studied by computation simulation. • The MIP was used to prepare a chemiluminescence sensor on 96-well microplate. • The sensor can simultaneously determine 8 benzimidazoles in meat sample. • The sensor achieves ultrahigh sensitivity (pg/mL) and can be reused for 4 times. Abstract In this study, a molecularly imprinted polymer capable of recognizing 8 benzimidazoles was first synthesized. The computation simulation showed that the shape and size of used template were the main factors influencing its recognition ability. Then the polymer was used as recognition reagent to prepare a chemiluminescence sensor on conventional 96-well microplate. The sample solution and a HRP-labeled hapten were added into the microplate wells to perform competitive binding, and the light signal was initiated with 4-(imidazol-1-yl)phenol enhanced luminol-H 2 O 2 system. The optimized sensor was used to determine the residues of 8 benzimidazoles in mutton and beef. Result showed that the sensor achieved ultrahigh sensitivity (limits of detection of 1.5–21 pg/mL), rapid assay process (18 min) and satisfactory recovery (65.8%–91.2%). Furthermore, this sensor could be reused for 4 times. Therefore, this sensor could be used as a rapid, simple, sensitive and durable tool for screening the residual benzimidazoles in meat. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fluorescent molecularly imprinted polymers (FMIPs) targeting ovalbumin were prepared. • The FMIPs have pH-dependent property for the recognition of ovalbumin. • The FMIPs can be used for ovalbumin assay in real samples with high recovery rate. Here, fluorescent artificial antibodies for sensing ovalbumin in food were synthesized by molecular imprinting technique in a microfluidic reactor. A phenylboronic acid-functionalized silane was employed as the functional monomer to enable the polymer has pH-responsive property. Fluorescent molecularly imprinted polymers (FMIPs) could be produced continuously in a short time. Both fluorescein isothiocyanate (FITC) and rhodamine B isothiocyanate (RB)-based FMIPs can specifically recognize the target ovalbumin, particularly FITC-based FMIP, giving an imprinting factor of 2.5 and cross-reactivity factors of 2.7 (ovotransferrin), 2.8 (β-lactoglobulin) and 3.4 (bovine serum albumin), and was applied for the detection of ovalbumin in milk powder with recovery rates of 93–110%; moreover, the FMIP can be reused at least four times. Such FMIPs have promising future in replacing the fluorophore-labelled antibodies to fabricate fluorescent sensing devices or establish immunoassay methods, which have extra merits of low-cost, high stability and recyclability, easy to carry and store at ambient environments. [ABSTRACT FROM AUTHOR]

A kanamycin molecular imprinted SPR sensor was prepared with 4-vinylbenzeneboronic acid as the functional monomer, polyethylene glycol acrylate and 2,2′-azo isobutyl amidine hydrochloride as the crosslinker and the initiator, respectively. Under optimum conditions, the response performance of the imprinted SPR sensor to kanamycin was evaluated. The imprinted sensor had a better imprinting effect and selectivity for kanamycin than the non-imprinted one. The linear range of imprinted sensor for kanamycin was from 1.0 × 10 −7 to 1.0 × 10 −5 mol/L (R 2  = 0.9941). Based on a signal-to-noise ratio of 3, the detection limits of kanamycin were 4.33 × 10 −8 mol/L for milk powder and 1.20 × 10 −8 mol/L for honey, with the RSD as 1.18% and 0.31%, respectively. [ABSTRACT FROM AUTHOR]

A new route to synthesize a covalent interaction-based molecularly imprinted polymer (MIP) material for 3-chloro-1,2-propanediol (3-MCPD) inside the nanopores of anodic alumina oxide (AAO) is presented. A series of adsorption experiments showed MIP had good extraction capacity and selectivity for 3-MCPD. In order to evaluate the usability of the MIP nanotubes membrane, a method combining AAO@MIP membrane extraction with gas chromatography – mass spectrometry (GC–MS) detection was developed for determination of chloropropanols. The limits of detection for the proposed method were 0.072 and 0.13 µg·L −1 , respectively, for 3-MCPD and 1,3-DCP. The average recoveries of 3-MCPD and 1,3-DCP spiked oil samples at three concentrations (0.01, 0.05 and 0.1 mg·kg −1 ) were in the range of 75.6–101.0% with a RSD of 3.3–8.4%, indicating the method would be suitable for determination of chloropropanols in vegetable oils. [ABSTRACT FROM AUTHOR]

A biomimetic enzyme-linked immunosorbent assay (BELISA) which was based on molecularly imprinted polymers on paper (MIPs-paper) with specific recognition was developed. As a detector, the surface of paper was modified with γ-MAPS by hydrolytic action and anchored the MIP layer on γ-MAPS modified-paper by copolymerization to construct the artificial antibody Through a series of experimentation and verification, we successful got the MIPs-paper and established BELISA for the detection of carbaryl. The development of MIPs-paper based on BELISA was applied to detect carbaryl in real samples and validated by an enzyme-linked immunosorbent assay (ELISA) based on anti-carbaryl biological antibody. The results of these two methods (BELISA and ELISA) were well correlated (R 2 = 0.944). The established method of MIPs-paper BELISA exhibits the advantages of low cost, higher stability and being re-generable, which can be applied as a convenient tool for the fast and efficient detection of carbaryl. [ABSTRACT FROM AUTHOR]

The 3D structures of two dummy templates and four phenothiazine drugs were studied by using computational simulation method. Then the two dummy templates were used to synthesize two molecularly imprinted polymers respectively. Results showed that the recognition abilities of the two polymers were consistent with the theoretical calculation. Then a solid phase extraction column was developed for extraction of the four phenothiazines in meat (pork, chicken) followed by determination with high performance liquid chromatography. The column showed high adsorption capacities (850–962 ng analyte per milligram of polymer) and high recoveries (93–98%) to the four drugs, and could be recycled for sixty times. The limits of detection were in the range of 1.0–10 ng/g, and the recoveries from the fortified blank samples were in the range of 70.3–96.1%. This is the first study reporting the use of molecularly imprinted polymer-based method for determination of phenothiazines residues in foods. [ABSTRACT FROM AUTHOR]

As an ideal biomimetic antibody, molecularly imprinted polymer (MIP) has shown great promise in immunoassays. Here, we developed a covalent imprinting method to prepare MIP artificial antibody towards clenbuterol on the well surface of a microtiter plate. Template molecule (clenbuterol) was splited by hydrolysis with functional monomer and removed by methanol/acetic acid solution, and then three-dimensional cavities were fabricated in the MIP, which can rebind template molecule via hydrogen bond interaction. Using this artificial antibody, we developed a novel biomimetic enzyme-linked immunosorbent assay (ELISA) with excellent sensitivity and specificity. The linear range for clenbuterol was 10 −5 to 1000 μg L −1 , with a detection limit of 10 −7 μg L −1 . Cross reactivity of this MIP artificial antibody to other four structural analogs was less than 0.93%. This method was applied to determine clenbuterol in real samples with satisfactory result, suggesting a promising application of the biomimetic ELISA in food and environmental analysis. [ABSTRACT FROM AUTHOR]

A series of molecularly imprinted polymers (MIPs) comprising reactionary sites which are complementary to macrolide antibiotic spiramycin (SPI) were synthetized by noncovalent bulk polymerization technique. MIPs were synthesized under different polymerization process and their recognition efficiency was evaluated in binding studies in comparison with non-imprinted polymers. The best MIP was morphologically characterized and equilibrium assays were carried out. The MIP was evaluated as a sorbent for extraction and preconcentration of SPI from aqueous and sheep milk samples, and an off-line MISPE method followed by high-performance liquid chromatography with UV diode-array detection was established. Good linearity were obtained for SPI in a range of 24–965 μg kg −1 and the average recoveries at three spiked levels in milk samples were higher than 90% (RSD < 5%). Limit of quantification was 24.1 μg kg −1 . Cross-reactivity studies from other macrolides with similar structure were tested. The optimum imprinted polymer showed a good selectivity and affinity for SPI, demonstrating the potential of the proposed MISPE for rapid, sensitive and effective sample pretreatment for selective determination of SPI in sheep milk samples. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor based on the molecularly imprinted polymer (MIP) was fabricated by electrochemical polymerization of β-cyclodextrins (β-CD) and epigallocatechin-gallate (EGCG) on the graphene oxide (GO) modified glassy carbon (GO/GC) electrode for the first time. The MIP/GO/GC electrode exhibits an excellent ability of specific binding of EGCG and a rapid electrochemical response, high sensitivity and selectivity for determination of EGCG. This prepared MIP sensor presents distinct advantages over conventional electrochemical methods for EGCG determination because it is a one-step preparation and the template molecule can be easily removed by cyclic voltammetry scans, and no elution reagent is required. Under the optimal experimental conditions, the linear response range for EGCG concentrations by the sensor was 3 × 10 −8 mol/L to 1 × 10 −5 mol/L and the detection limit was 8.78 × 10 −9 mol/L(S/N = 3). The results demonstrate that the proposed MIP sensor can be a potential alternative for the determination of EGCG in tea samples. [ABSTRACT FROM AUTHOR]

Pesticide residue in vegetables is a serious problem that has adverse effects on human health. In our study, we designed and synthesized a molecularly imprinted polymer that can selectively recognize trichlorfon. Using the polymer material as biomimetic antibody, we developed a biomimetic immunoassay-capillary electrophoresis method with improved sensitivity for the detection of trichlorfon. We evaluated the competitive reactions between HRP labeled trichlorfon hapten and free trichlorfon with the biomimetic antibody. Factors that affected the sensitivity of our method were tested in detail. Under optimal conditions, the limit of detection (LOD, IC 15 ) and the sensitivity (IC 50 ) of this method were 0.16 mg L −1 and 0.13 μg L −1 for trichlorfon. We used this method to determine the trichlorfon spiked in the kidney bean and cucumber samples with recoveries ranging from 78.8% to 103%. We also detected residual trichlorfons in the leek samples, and these results were verified by gas chromatography method. [ABSTRACT FROM AUTHOR]

17β-estradiol (17β-E 2 ) usually is used to promote the growth of animal. Abuse of 17β-E 2 has become a global food security problem, because the residues in foods can cause endocrine disorder through the food chain. A novel molecularly imprinted polymer (MIP) grafted paper-based method for the sensitive and specific detection of 17β-E 2 was reported in this work. Results showed that the MIP’s optimum synthetic conditions were as follows: 12 mL of acetonitrile was chosen as the solvent; the molar ratio of template molecule, functional monomer and cross linker was 1:12:12. MIP synthesized had a good recognition ability, the limit of detection (LOD) of established detection method for milk and human urine samples could reach 0.25 μg L −1 . [ABSTRACT FROM AUTHOR]

• A novel molecularly imprinted polymer was fabricated for Fenamiphos. • A low limit of detection (7.13 nM) was achieved at MIP-Au@MOF-235@g-C 3 N 4. • The sensor can be applied to detect Fenamiphos in real samples. A noninvasive material-based electrochemical sensor continuously monitors the fenamiphos (FMS) level in vegetable samples is highly desirable for innovative fabrics to check the health of agricultural products. Herein, an electrochemical sensor is fabricated by a sensitive molecularly imprinted polymers/metal–organic framework/gold stabilized on graphite carbon nitride (MIP-Au@MOF-235@g-C 3 N 4) for monitoring the FMS level in real samples continuously with high sensitivity and accuracy. The MIP-based sensor was simply produced by a hydrothermal strategy. The MIP-Au@MOF-235@g-C 3 N 4 had a large specific surface area and high catalytic activity, which enables the fabricated sensor with good electrochemical performance with a high sensitivity of 1.07 μA.μM−1 and a wide linear range of 0.01 to 16.4 μM. The proposed strategy was applied to determine FMS in agricultural products with satisfactory recoveries (94.7–107.9%) and a relative standard error of less than 1.0%, providing novel tactics for the rational design of MIP-sensors to determine a growing number of deleterious substances. [ABSTRACT FROM AUTHOR]

A novel molecularly imprinted polymer (MIP) based on hydrophobic CdSe/ZnS quantum dots (HBQDs) was synthesized via an approach that combines MIPs for the selectivity and sensitivity with semiconductor HBQDs as optosensing material (HBQDs@MIP). Here, using a one-pot water-in-oil reverse microemulsion polymerization, the HBQDs@MIP was used as a molecular recognition element to construct an N ε -carboxymethyllysine (CML) optosensor. The HBQDs were coated with silica to endow the nanoparticles with high dispersibility and broad compatibility with hydrophilic analytes. Under optima conditions, the relative fluorescence intensity of the HBQDs@MIP decreased linearly with increasing CML concentration in the range 5–400 μg L −1 . The proposed method enables, detection procedures to be completed within 90 min, with good recoveries, ranging from 85% to 106%. It can be applied to the rapid and cost–effective monitoring of CML in food samples. [ABSTRACT FROM AUTHOR]

In the present communication, a non-covalent fenarimol-imprinted polymer was synthesized by precipitation polymerization technique using methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a cross-linker, and azobisisobutyronitrile (AIBN) as an initiator in different porogenic solvent. Binding study of molecularly imprinted and non-imprinted polymer (MIP and NIP) showed that MIP possesses a higher affinity towards this analyte compared to NIP. The binding affinity of MIP was calculated by static and kinetic adsorption study. Further, a MIP based cartridge was designed to use in extraction process, necessary for specific determination and quantification of the fungicide in food matrices. Under the optimum conditions, developed method was found to be linear ( R 2 = 0.9999–0.9994). Limit of detection (LOD) and limit of quantitation (LOQ) in samples were 0.03–0.06 and 0.12–0.21 μg mL −1 , respectively. The rate of recovery of fenarimol was 91.16–99.52% on MIPs. The validated method of molecularly imprinted solid-phase extraction (MISPE) cartridge was successfully applied to the food matrices and compared with commercial sorbent (RP18 and Oasis HLB). However we feel, this method has promising applications in the routine analysis of food samples in industry. [ABSTRACT FROM AUTHOR]