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The poor biological, mechanical and water-resistance properties of sodium alginate/guar gum film (SG) limit its application in food preservation. To overcome this disadvantage, we added β-Cyclodextrin/persimmon pectin-stabilized baobab seed oil Pickering emulsion (BOPE) to enhance the mechanical and water resistance properties of SG film, and added green synthesized silver nanoparticles (AgNPS) and Lycium ruthenicum extract (LA) to improve the biological properties of the film. The properties of BOPE was optimized using Box-Behnken design (BBD). Scanning electron microscope and Fourier transform infrared results revealed the change of structure and molecular interaction in the SG film after the addition of AgNPS, LA, and optimized BOPE. The 2.0%BOPE-loaded film containing AgNPS/LA with the enhanced mechanical, barrier, BO retention, and biological properties not only improved the preservation effect on mushroom (A. bisporus), but also maintained structural stability. Thus, the 2.0%BOPE-loaded SG/LA/AgNPS film has considerable potential in active packaging applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

A ratiometric fluorescence sensor based on dual-emission carbon quantum dots (CQD) was developed to real time monitor food spoilage. Two hydrophobic electrospun fluorescent films were developed using polyvinylidene fluoride (PVDF) as the film-forming polymer in combination with CQD as the fluorescent probe. The CQD/PVDF film and CQD@PVDF film enabled the analysis of TMA with limits of detection (LODs) of 1.04 μM and 2.1 μM, respectively, and they exhibited excellent stability at 4 °C. By these virtues, the CQD@PVDF film exhibited visible fluorescence color changes from yellow green to blue by real time and nondestructively sensing volatile amines generated from beef, pork and shrimp in a packaging system with high humidity. This strategy provided a simple but useful, non-destructive, robust, and platform to real time monitor food spoilage for intelligent food packaging., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

The gelatin/gellan gum based-bilayer emulsion film was developed in this work to improve the survivability of Bifidobacterium longum during the storage process. The baobab seed oil (BO) was added to the gelatin (GE) matrix to develop emulsion film as the barrier outer layer. The blueberry anthocyanin extract (BE) was incorporated into the gellan gum (GG)-based inner layer to enhance the viability of B. longum. The SEM and FTIR results revealed that the probiotics were successfully entrapped in BO/BE-loaded bilayer film. The greatest survivability and viable cell numbers of the B. longum during the storage period were observed in the BO/BE loaded bilayer film. Furthermore, the stability of the colorful patterns by electrochemical writing was also evaluated in this work. Finally, the GE/BO-GG/BE/BM maintain satisfactory probiotic viability in steamed bread coating application. Hence, the GE/BO-GG/BE/BM bilayer film could be considered a novel material to deliver and protect the probiotics in food applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The Transient Receptor Potential Vanilloid 1 (TRPV1) has been identified as a suitable candidate for a spicy taste (Zanthoxylum plant) sensor. In this study, we investigated the response of TRPV1 expressed on human HepG2 cell membranes following stimulation with Hydroxy-α-sanshool. A three-dimensional (3D) cell-based electrochemical sensor was fabricated by layering cells expressing hTRPV1. l-cysteine/AuNFs electrodes were functionalized on indium tin oxide-coated glass (ITO) to enhance the sensor's selectivity and sensitivity. HepG2 cells were encapsulated in sodium alginate/gelatin hydrogel to create a 3D cell cultivation system, which was immobilized on the l-cysteine/AuNFs/ITO to serve as biorecognition elements. Using differential pulse voltammetry (DPV), the developed biosensor was utilized to detect Hydroxy-α-sanshool, a representative substance in Zanthoxylum bungeanum Maxim. The result obtained from DPV was linear with Hydroxy-α-sanshool concentrations ranging from 0 to 70 μmol/L, with a detection limit of 2.23 μmol/L. This biosensor provides a sensitive and novel macroscopic approach for TRPV1 detection., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

A visual Polyvinylidene Fluoride (PVDF) fibrous film incorporated with Roselle anthocyanin (RS) and Cinnamon essential oil (CEO) (PRC film) was designed via electrospinning technology for pork preservation and freshness monitoring. The PRC film presented well structural integrity and stability in buffer solutions without leaking out RS. And PCR film had well hydrophobic and high permeability with water contact angle (WCA) of 109.52° and water vapor permeability (WVP) of 2.63 × 10 -7  g m -1 h -1 Pa -1 . Importantly, PRC film exhibited good antibacterial activity with the inhibition diameter at 29.0 mm and 27.1 mm which against Escherichia coli and staphylococcus aureus, respectively. Finally, the PRC film was employed as a colorimetric sensor for monitoring pork freshness. It presented visible color changes from pink to blue and effectively prolonged the pork shelf-life by 2 days at 4 °C. These results indicate a great potential in intelligent and active packaging., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

A novel bilayer colorimetric film incorporating polycaprolactone (PCL) with clitoria ternatea Linn anthocyanin (CA) via electrospinning was designed. The PCL nanofibers layer acted as a protective layer against harsh environments as the strong hydrophobic with the WCA (water contact angle) values of 101.79°. The PCL-CA layer worked as an indicator for its significant color changes for pH. The sensitivity test verified the ammonia cycler reversibility of the nanofibers is promising for re-use packaging. And the PCL/PCL-CA film was characterized as suitable WVP (water vapour permeability), and the lower velocity of water penetrating. Moreover, higher elongation at break (240.431%), and color stability were achieved. Besides, the film exhibited the color change from pale-blue to yellow-green response as an indication of shrimp spoilage (21 h). These results suggested the potential application of the PCL/PCL-CA film for a reusable freshness sensor tool in food packaging., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This study designed a new type indicator with hydrophobic Polyvinylidene Fluoride (PVDF) film as a moisture prevent-layer. And the sensor layer was provided based on polyvinyl alcohol/Sodium alginate (PS) and Roselle anthocyanins (RAs). Physical properties, microstructure, and color stability of the bi-layer indicator have been investigated. The Water contact angle (WCA) of PS/RAs/ PVDF film (PSRF) was 108.85°, which can be considered as an excellent hydrophobic surface. The lowest Water Vapor Permeability (WVP) value of PSRF exhibited a good barrier property for moisture. Therefore, PSRF film was used to monitor the griskin freshness. The Total volatile basic nitrogen (TVB-N) level was increased to 18.02 mg/100 g at 72 h, and the color of the indicator presented visible color changes. The acquired results revealed a good correlation between TVB-N, pH and color change of the indicator. The research indicated that PSRF indicator has increasing potential application on food intelligent packaging., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

This work presents an electrochemical device based on a composite modification of amine functionalized Zr(IV) metal-organic framework (UiO-66-NH 2 ) and multi-walled carbon nanotubes (MWCNTs) for voltammetry determination of cadmium ions (Cd 2+ ). The UiO-66-NH 2 @MWCNTs composites were prepared by one-pot hydrothermal reaction. The prepared sensor performs excellent performance, which was attributed to the synergism between UiO-66-NH 2 with a special octahedral structure and enlarged surface area and MWCNTs with outstanding conductivity. Under optimal experiment condition, the fabricated sensor showed good linear relationship from 0.5 to 170 μg/L, with a detection limit of 0.2 μg/L. Finally, the sensor was successfully applied to detect Cd 2+ in meat samples (N = 21) with relative standard deviation (RSD) lower than 4.5% and recovery of 95.1-107.5%, and the results were compared with certified method, there was no statistical significance difference between the developed sensor and certified method at a 95% confidence level., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Carbon quantum dots (CQDs) prepared by a green one-step approach was used for sensitive and selective assay of Escherichia coli O157: H7 (E. coli). CQDs was synthesized from orange peel as a carbon source via a microwave-assisted method. The CQDs displayed strong green fluorescence under excitation wavelength of 420 nm. A fluorescent probe (CQDs-MNPs) for E. coli was fabricated based on CQDs labeled with aptamer (aptamer-CQDs) and magnetic nanoparticles labeled with complementary DNA (cDNA-MNPs). Fluorescent intensity of the CQDs-MNPs was decreased with addition of E. coli. The linearity between fluorescent intensity and E. coli concentration was used for developing a fluorescent method with detecting range of 500-10 6 CFU/mL and detection limit of 487 CFU/mL. Milk samples contaminated by E. coli were analyzed by this method, and the results agreed with that achieved by plate-counting methods. This fluorescent probe exhibits great potential in guaranteeing food quality and safety., (Copyright © 2020. Published by Elsevier Ltd.)

Fish consumption is the main source of methylmercury (CH 3 Hg + ) exposure for humans. In this study, gold nanoparticles and reduced graphene oxide (AuNPs-RGO) modified electrode was fabricated for determination of CH 3 Hg + in fish. The AuNPs-RGO composite was synthesized by electroreduction method. The composite was characterized by scanning electron microscopy and energy dispersive spectra, X-ray diffraction and Raman spectroscopy. Electrochemical performance of the proposed sensor was studied by cyclic voltammetry, electrochemical impedance spectroscopy and differential pulse stripping voltammetry. The excellent conductivity and large surface of graphene contributed to an improvement in the voltammetric stripping signal. Under the optimized conditions, the methylmercury concentration in the range from 3 to 24μgL -1 had a good linear relation with the peak current. The detection limit of AuNPs-RGO modified electrode was 0.12μgL -1 . Finally, the developed electrode was applied to detect methylmercury in fish samples, and the obtained results were in good agreement with certified values., (Copyright © 2017 Elsevier Ltd. All rights reserved.)