Area Of Food Safety Research Articles

Shell-Isolated Nanoparticle-Enhanced Raman Spectroscopy: Toward High Sensitivity and Broad Applicability.

As a nondestructive and ultrasensitive technique, surface-enhanced Raman spectroscopy (SERS) has captivated the attention of the global scientific community for over 50 years. Among the various spectroscopic techniques derived from SERS, shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) stands as a cutting-edge advancement. The innovative and versatile core-shell nanoparticle structures used in SHINERS have emerged as an ideal platform for interfacial research, offering high sensitivity and broad applicability across diverse materials and single-crystal surfaces. Consequently, SHINERS has seen widespread adoption in pivotal fields, such as interface chemistry, electrocatalysis, biomedicine, materials, and food safety. In this Perspective, we outline the evolutionary journey of SHINERS, delve deep into its applications in fundamental research for interface characterization and catalysis, and explore its practical utility in critical areas of food safety and biomedicine analysis. Additionally, we map out the prospective trajectory and future milestones that await SHINERS as it continues to revolutionize the landscape of scientific exploration.

Deep-Eutectic-Solvent-Decorated Metal–Organic Framework for Food and Environmental Sample Preparation

Deep eutectic solvent (DES) is distinguished by its unique solvent properties, chemical stability, and eco-friendly nature, which are pivotal in a spectrum of chemical processes. It enhances the sample preparation process by increasing efficiency and minimizing the environmental impact. Metal–organic frameworks (MOFs), which are porous structures formed through coordination bonds between metal ions and organic ligands, are defined by their adjustable pore dimensions, extensive surface areas, and customizable architectures. The integration of DES within MOF to create DES@MOF capitalizes on the beneficial attributes of both materials, augmenting MOFs’ stability and versatility while providing a multifunctional carrier for DES. This composite material is both highly stable and readily tunable, establishing it as a leading contender for applications in sample preparation for food and environmental samples. This comprehensive review explores the application of DES-decorated MOF in food and environmental sample preparation and highlights the expansive potential of DES@MOF in diverse fields. We provide a detailed analysis of the characteristics of DES@MOF and its individual components, methods for decorating MOFs with DES, the advantages of these composite materials in sample pretreatment, and their specific applications in food safety and environmental monitoring. DESs are employed to modify MOFs, offering a multitude of benefits that can substantially improve the overall performance and applicability of MOFs. The review also discusses current challenges and future directions in this field, offering valuable insights for further research and development. The synergistic effects of DES and MOFs offer new opportunities for applications in food safety and other areas, leading to the development of more efficient, sensitive, and environmentally friendly analytical methods. This collaboration paves the way for sustainable technologies and innovative solutions to complex challenges.

Fabrication of natural enzyme-covered / amino-modified Pd-Pt bimetallic-doped zeolitic imidazolate framework for ultrasensitive detection of metabolites.

The present article introduced an natural enzyme-covered/amino-modified Pd-Pt bimetallic-doped zeolitic imidazolate framework (NAPPZ) for ultrasensitive and specific detection of glucose. The dodecahedral nanomaterial zeolitic imidazolate framework (ZIF-8)-loaded Pd-Pt bimetallic nanoparticles endowed the composite with peroxidase-like activity. The modification with glucose oxidase (GOx) facilitated the rapid access of H2O2 produced through glucose oxidation to the Pd-Pt nanoparticles vicinity reducing diffusion. GOx specifically catalyzes the transformation of glucose into H2O2, which then H2O2 rapidly migrates to the Pd-Pt nanoparticles, catalyzing the oxidation of colorless o-phenylenediamine into the orange-yellow product 2,3-diaminophenazine. Based on the aforementioned cascade reaction, the NAPPZ and NAPPZ based on ChOx were utilized for detecting glucose in human urine samples and cholesterol in milk, respectively. The NAPPZ strategy presented a broad detection range (20-1100μmol L-1) and a low detection limit (15.9μmol L-1) for glucose, and the NAPPZ based on ChOx strategy approach offered a broad detection range (10-500μmol L-1) and low detection limit (6.4μmol L-1) for cholesterol. Therefore, this novel method holds significant potential in the areas of clinical diagnostics and food safety.

Risk-benefit assessment of foods and its role to inform policy decisions: outcome of an international workshop.

Policy decisions in public health require consideration and evaluation of trade-offs for which transparency and science-based evidence is needed. Improvement of decision-support tools is essential to help guide food policy decisions that promote healthy diets and meet the challenges of food systems without compromising food security, food safety, and sovereignty. Risk-benefit assessment of foods (RBA) is an established methodological approach designed to inform policy decisions within the area of nutrition and food safety. Despite methodological developments, translation of RBA findings into policies is still limited. In this context, a stakeholder workshop held in May 2023 gathered RBA experts and food regulators from Europe to identify the challenges, obstacles and opportunities in using evidence generated through RBAs to inform food policy decisions. A structured process was implemented to collect their views through online surveys, breakout groups, and plenary discussions. As a secondary objective, food regulators' views on other approaches for holistic risk assessment fit for food systems analysis were also explored. This paper summarizes the main findings of the workshop and discusses policy implications and future perspectives to improve the area of RBA and its role in food policymaking.

Reproducible, Accurate, and Sensitive Food Toxin On-Site Detection with Carbon Nanotube Transistor Biosensors.

Field-effect transistor (FET) biosensors based on nanomaterials are promising in the areas of food safety and early disease diagnosis due to their ultrahigh sensitivity and rapid response. However, most academically developed FET biosensors lack real-world reproducibility and comprehensive methodological validation to meet the standards of regulatory bodies. Here, highly uniform and well-packaged semiconducting carbon nanotube (CNT) FET biosensor chips were developed and assessed for the plug-and-play sensing for the rapid and highly sensitive detection of aflatoxin B1 (AFB1) in real food samples to meet international standards. In order to meet the requirements for reproducibility and stability, a scalable residual-free passivation and packaging process was developed for CNT FET biosensors. Portable detection systems were then constructed for on-site detection. The resulting packaged chips were functionalized with nucleic aptamers to enable highly selective detection of AFB1 in food samples with a detection limit (LOD) of 0.55 fg/mL (standard) for AFB1 and cross-reactivity coefficients to interferences as low as 1.8 × 10-7 in simulated solutions. Utilizing the portable detection system, on-site real food detection was achieved with a rapid response time less than 60 s, and LOD of 0.25 pg/kg (standard) in complex corn sample matrices. Single-blind tests demonstrated the ability of the chips to detect AFB1-positive food with 100% accuracy, using a set of 30 peanut samples. Validation experiments confirmed that the detection range, stability, and repeatability met international standards. This study showcased the accuracy, reliability, and potential practical applications of CNT FET biosensor chips in areas such as food safety and rapid biomedical testing.

EFSA's activities on emerging risks in 2022

Abstract The main objectives of EFSA's activities on emerging risks encompass: (i) conducting activities to identify emerging risks; (ii) developing and improving emerging risk identification (ERI) methodologies and approaches; and (iii) communicating identified issues and risks. The outcome of these activities equips EFSA to anticipate forthcoming challenges in the continuously evolving landscape of risk assessment. EFSA networks of knowledge contributing to the emerging risks identification activity include the Emerging Risks Exchange Network (EREN), the Stakeholder Discussion Group on Emerging Risks (StaDG‐ER), EFSA's scientific units, the scientific panels, the Scientific Committee and their working groups. The current technical report summarises the activities of all groups involved in the emerging risk identification procedure, the issues identified in the course of 2022, the emerging risk identification methodologies being developed, and the collaborative activities. In total, 13 potential emerging issues were discussed in 2022 and two were concluded to be emerging risks. The potential issues were classified according to the hazard. The year 2022 marks a turn in EFSA's activities on emerging risk identification. To achieve strategic objective no. 2 ‘Ensure preparedness for future risks analysis needs’ of the EFSA Strategy 2027, a new process ‘Environmental scanning and strategic options definition’ has been developed. The process adds to the already existing emerging risks analysis workflow a second workflow that is more forward‐looking, to deal with horizon scanning in the areas of food and feed safety, plant health and animal health. Similarly to the emerging risks analysis workflow, the new workflow for horizon scanning strongly relies on partnership to be prepared for future challenges, build resilience, and proactively shape the future in a one‐health approach.

Phytochemical Analysis and Antioxidant and Antifungal Activities of Powders, Methanol Extracts, and Essential Oils from Rosmarinus officinalis L. and Thymus ciliatus Desf. Benth.

Chemical residues in food pose health risks such as cancer and liver issues. This has driven the search for safer natural alternatives to synthetic fungicides and preservatives. The aim of this study was to characterize the chemical composition of the essential oils (EO), determine the polyphenolic contents, and evaluate the in vitro antioxidant and antifungal activities of methanol extracts (ME), essential oils (EO), and powders from Rosmarinus officinalis L. (rosemary) and Thymus ciliatus (Desf) Benth. (thyme) from the M'sila region, Algeria. The chemical composition of the EOs was determined by GC-MS. R. officinalis EO was composed of 31 components, mainly camphor (41.22%), camphene (18.14%), and α-pinene (17.49%); T. ciliatus EO was composed of 58 components, mainly, in percentage, α-pinene (22.18), myrcene (13.13), β-pinene (7.73), β-caryophyllene (10.21), and germacrene D (9.90). The total phenols and flavonoids were determined spectrophotometrically, and the rosemary ME was found to possess the highest polyphenolic content (127.1 ± 2.40 µg GAE/mg), while the thyme ME had the highest flavonoid content (48.01 ± 0.99 µg QE/mg). The antioxidant activity was assessed using three methods: rosemary ME was the most potent, followed by DPPH (IC50 = 13.43 ± 0.14 µg/mL), β-carotene/linoleic acid (IC50 = 39.01 ± 2.16 μg/mL), and reducing power (EC50 = 15.03 ± 1.43 µg/mL). Antifungal activity was assessed for 32 pathogenic and foodborne fungi. Four methods were applied to the solid medium. Incorporating the powdered plant into the culture medium (at 10%) reduced the fungal growth to greater than 50% in 21.88% and 6.25% of all fungal isolates, for R. officinalis and T. ciliatus, respectively. The ME, applied by the well diffusion method (0.1 g/mL), was less effective. Different concentrations of EO were tested. Incorporating the EO into the culture medium (1500 μL/L) inhibited 50% of the molds to levels of 50 and 75% for R. officinalis and T. ciliatus, respectively, with the complete inhibition of four fungi. Fumigated EO (15 μL) inhibited 65% of the molds to levels of 65 and 81.25% for R. officinalis and T. ciliatus, respectively, with the complete inhibition of five fungi. There was little to no sporulation in conjunction with the inhibition. Our results revealed some of the potential of the studied plants to fight foodborne molds and presented their promising characteristics as a source of alternatives to chemical pesticides and synthetic preservatives. Further studies are needed to find adequate application techniques in the food safety area.

Food safety knowledge and practices of food handlers at a public Sudanese university

The study was conducted to evaluate food safety knowledge and practices of food handlers in twenty-four food premises at nine campuses of Sudan University of Science and Technology (SUST), Khartoum State, Sudan. A structured questionnaire about demographic characteristics, food safety knowledge and practices of one hundred and five respondents was used. Data showed that 95.2% of respondents were Sudanese; 99% were males, the majority were singles, 43.8% were university graduates, 64.8% were in the age group 20-30 years, 100% had good knowledge regarding the importance of maintaining a clean environment in food premises, preparing food in a safe way, danger of food poisoning and 95.4% agreed that it is their responsibility to prevent food poisoning. Food handlers had in general satisfactory practices of personal hygiene; however, 64.8 to 69.5% had some poor practices, particularly not wearing clean aprons, masks, gloves and hair nets. Among the respondents 68.6% received basic training in food safety. The study suggests that mandatory food safety education and training should be organized to strengthen food handlers' knowledge, attitudes and practices in food safety areas which are either weak or lacking. The HACCP system should be implemented in food premises at the university campuses.

Dual-sensitized heterojunction Ag2S/ZnS/NiS composites with entire visible-light region absorption for ultrasensitive photoelectrochemical detection of tobramycin

In this study, an ultrasensitive photoelectrochemical (PEC) aptasensor based on dual-sensitized heterojunction Ag2S/ZnS/NiS composites as a signal probe was proposed for the detection of tobramycin (TOB) by combining a cascaded quadratic signal amplification strategy. Specifically, compared to the limited visible light-harvesting capability of single sensitized composites, Ag2S/ZnS/NiS composites with p-n and n-n heterojunction could greatly improve the light energy utilization to tremendously strengthen the optical absorption in the entire visible-light region. Moreover, dual-sensitized heterojunction could effectively hinder the rapid recombination of photoelectrons and holes (carriers) to obtain a good photocurrent for improving the sensitivity of the aptasensor. Furthermore, a cascaded quadratic signal amplification strategy was applied to convert trace target TOB into plentiful gold nanoclusters (Au NCs) labelled double-stranded DNA for the construction of PEC aptasensor, with a broad linear detection range from 0.01 to 100 ng mL−1 and a low detection limit of 3.38 pg mL−1. Importantly, this study provided a versatile and sensitive PEC biosensing platform for TOB analysis, and demonstrated its successful application for TOB detection in milk samples. This protocol provides a novel dual-sensitized heterojunction composites to develop a highly efficient and harmfulless PEC aptasensor, which is expected to be used in food safety, environmental monitoring and other areas.

A novel albumin-based supramolecular biosensor for ratiometric on-site determination of buprofezin

Buprofezin (BUP) is an effective insecticide against Homopteran and Thysanoptera pests. However, exposure to BUP may result in several harmful effects on the non-target organism including human body, such as hepatotoxicity and DNA damage. Therefore, development of a reliable analytical method for BUP holds paramount importance. This study presents a novel albumin-based supramolecular biosensor, DPP@ALB, designed for the sensitive detection of BUP in environmental matrices, including water, soil, and real food samples. The features of this biosensor include a fast response, high sensitivity, and visually detectable fluorescence color change, enabling on-site detection of BUP based on the portable paper strips and 3D-printed miniaturized testing system. Overcoming challenges associated with the low chemical reactivity of BUP, this supramolecular biosensor emerges as the very first fluorescent sensor for efficient and reliable monitoring of BUP with applications in broader areas of environmental analysis and food safety.

Rapid DNA extraction and microfluidic LAMP system in portable equipment for GM crops detection

Genetically modified food has come under suspicion because of the potential safety risks. Only a limited number of target genes could be detected by traditional methods. Here, customized-fast DNA extraction methods and a LAMP (Loop-mediated isothermal amplification) system were developed combining with a hand-held chip, a portable analyzer, and an Android App for the qualitative detection of genetically modified crops. DNA of seeds and leaves was obtained within 5 minutes. Primers were designed with high specificity and sensitivity (10 copies) for later LAMP amplification. Crude DNA was added to the chip pre-embedded with customizable primers by quantitative dropper and the whole detection process was less than 40 minutes without any large-scale instrument. The 0.1% quality percentage of GM samples (maize or soybean) could be detected by the detection system. The detection system with its low workload, high accuracy, and stability offers a novel and effective approach for the rapid detection of GM crops and many other food safety areas in the field.

Ingestion and polymeric risk assessment of microplastic contamination in commercially important brachyuran crab Portunus sanguinolentus

Microplastic (MP) in seafood is a growing area of food safety. In the present study, MP contamination in the commercially important crab Portunus sanguinolentus was assessed. A total of 300 crab specimens were collected from three principal fishing harbors of Gujarat. The collected specimens were analyzed for MPs isolation using a previously published protocol. The specimens were dissected, and organs such as the gut and gills were placed separately in the beaker. The organic tissues were digested using 10% KOH. After the digestion, flotation and filtration processes were carried out for the extraction of MPs. The physical (shape, size, and color) and chemical characterization of MPs were performed. The average abundance of MP was recorded as 0.67 ± 0.62 MPs/g. The pollution indices revealed very high contamination and fell under class IV (Jakhau) and V risk categories (Okha and Veraval). Microfibers were found dominantly. Blue and black-colored MPs with 1–2 mm sizes were recorded dominantly. Polyethylene, polyethylene tetraphene, polyurethane, polystyrene, and polypropylene were identified as polymer compositions of MPs. Concludingly, the present study gives an insight into the MP in an important crab species P. sanguinolentus, which can be useful to design further investigations on the toxicity of MPs in seafood.

Translating risk-benefit assessment evidence for policy making: outcomes of an international workshop

Abstract Background Transitioning to sustainable, healthy, and inclusive food systems requires a multi-domain risk analysis approach. Integrated methods, such as health risk-benefit assessment (RBA), can support the formulation of coherent regulations by providing comparative information on potential trade-offs within the areas of food safety and nutrition. Despite extensive scientific developments and applications, RBAs have not yet been fully adopted by regulatory bodies. Hence, participatory science is needed to identify obstacles for implementation and communication of RBAs to optimize and ensure that generated evidence is compatible to regulatory needs. Methods As part of the EU funded project HOLiFOOD, an international workshop held in May 2023 brought together food regulators and other stakeholders from across Europe to identify bottlenecks in the use of RBA outputs in decision-making. The meeting included a key-note presentation, surveys, and group discussions. Results Thirty-seven participants from 19 institutions based in 13 countries attended the workshop. Obstacles identified were classified into one of the following themes: challenges of using RBAs to inform policymaking, opportunities and needs (e.g., reliability of methods), and communication of RBA outputs. Case studies targeting various foods groups or diets in different contexts is recommended. Conclusions Health RBA is a multidisciplinary method useful for prioritizing actions and ensuring transparency in decision-making. Case studies addressing the identified obstacles could increase the reliability of RBA methods and favour the adoption by regulatory bodies. Finally, moving towards holistic approaches may require further cross-departmental collaboration and, potentially, organizational changes of authorities in the future. Key messages • Risk-benefit assessment of foods is a robust tool to support public health policymaking. • Engagement with risk managers and other stakeholders is essential to deliver, and effectively translate, fit-for-purpose scientific evidence.

Mitigating and preventing food insecurity: a scoping review of the current EU policies

Abstract Background Food insecurity (FI) is a major public health concern, due to its association with a variety of adverse health outcomes. The aim of this study is to provide a picture of the EU policy response and adherence to the international recommendations in terms of FI mitigation and prevention. Methods A scoping review was carried out based on PRISMA Extension for scoping reviews method. By using specific queries/keywords, Pubmed and Scopus were searched and also institutional databases: EUR-Lex, WHO Global Database on the Implementation of Nutrition. The search was supplemented by a review of a list of organizations’ official websites, including Cordis, Food and Agriculture Organization of the United Nations, United Nations International Children's Emergency Fund and World Food Programme. Results The search on PubMed and Scopus produced a list of 8 articles, 3 concerning agriculture policies in EU, 4 related to intervention on the school lunch and 1 focused on the introduction of a tax on unhealthy drinks. Based on the search on EUR-Lex and WHO Global Database on the Implementation of Nutrition, 4 EU-wide statutory policies were collected covering school meals, food loss reduction, food waste prevention and food crisis and humanitarian aid operations. The institutional website's review returned 18 documents in the form of ‘soft law’ measures, including action plans, action tools and projects. Conclusions Preliminary findings suggest that currently, at EU level, a coherent specific policy framework on FI is lacking. The policy fragmentation is mainly due to the multidimensional nature of FI, which has interconnections with multiple and different areas of food system-food availability, food accessibility, food safety and food quality and healthiness. The outputs also show that to date EU has failed to adhere to the international recommendations (above all, WHO recommendations) on FI mitigation and prevention. This has significant implications in terms of public health. Key messages • Policies design and implementation have the potential to create living environments conducive to good health and to lead to concrete health gains. • Health gains resulting from strategies and policies implementation against FI reduce healthcare costs associated with the treatment of the FI-related diseases.

Emerging Applications of Nanobiosensors in Pathogen Detection in Water and Food.

Food and waterborne illnesses are still a major concern in health and food safety areas. Every year, almost 0.42 million and 2.2 million deaths related to food and waterborne illness are reported worldwide, respectively. In foodborne pathogens, bacteria such as Salmonella, Shiga-toxin producer Escherichia coli, Campylobacter, and Listeria monocytogenes are considered to be high-concern pathogens. High-concern waterborne pathogens are Vibrio cholerae, leptospirosis, Schistosoma mansoni, and Schistosima japonicum, among others. Despite the major efforts of food and water quality control to monitor the presence of these pathogens of concern in these kinds of sources, foodborne and waterborne illness occurrence is still high globally. For these reasons, the development of novel and faster pathogen-detection methods applicable to real-time surveillance strategies are required. Methods based on biosensor devices have emerged as novel tools for faster detection of food and water pathogens, in contrast to traditional methods that are usually time-consuming and are unsuitable for large-scale monitoring. Biosensor devices can be summarized as devices that use biochemical reactions with a biorecognition section (isolated enzymes, antibodies, tissues, genetic materials, or aptamers) to detect pathogens. In most cases, biosensors are based on the correlation of electrical, thermal, or optical signals in the presence of pathogen biomarkers. The application of nano and molecular technologies allows the identification of pathogens in a faster and high-sensibility manner, at extremely low-pathogen concentrations. In fact, the integration of gold, silver, iron, and magnetic nanoparticles (NP) in biosensors has demonstrated an improvement in their detection functionality. The present review summarizes the principal application of nanomaterials and biosensor-based devices for the detection of pathogens in food and water samples. Additionally, it highlights the improvement of biosensor devices through nanomaterials. Nanomaterials offer unique advantages for pathogen detection. The nanoscale and high specific surface area allows for more effective interaction with pathogenic agents, enhancing the sensitivity and selectivity of the biosensors. Finally, biosensors' capability to functionalize with specific molecules such as antibodies or nucleic acids facilitates the specific detection of the target pathogens.

CEC04-01: Perception of chemical substances – insights from social research at EU level in the area of food safety

CEC04-01: Perception of chemical substances – insights from social research at EU level in the area of food safety

The potential for foodborne disease stemming from the consumption of quail products: A systematic review

Background and Aim: Investigation of the zoonotic potential of quail-derived food items, including eggs and meat, and their consequential impact on the health of the general population is insufficient. The present study provides a comprehensive overview of the potential hazards associated with consuming quail eggs and meat products with a One Health approach based on the existing body of knowledge derived from multi-disciplinary studies. Materials and Methods: A total of 37 studies from 2004 to 2021 were procured from four distinct databases following a two-stage screening process involving practical and methodological screening. The utilization of a descriptive qualitative method with a meta-aggregation approach was employed to scrutinize these studies, leading to a definitive conclusion regarding the risks of foodborne diseases associated with the consumption of quail meat products. Results: A total of 7555 studies were retrieved and 146 were qualified based on the predetermined criteria. Of 146 studies, 90 studies were eliminated based on duplication screening. Of the 90, 37 were determined to be related to the aim of this research. Conclusion: The consumption of quail eggs and meat products poses a significant risk for foodborne diseases, with potentially greater ramifications than currently recognized, particularly in the areas of food safety, public health, conservation, and the economy. Keywords: foodborne disease, One Health, quail.

Food Risk Analysis: Towards a Better Understanding of "Hazard" and "Risk" in EU Food Legislation.

For risk communication, it is important to understand the difference between "hazard" and "risk". Definitions can be found in Codex Alimentarius and the European Union (EU) General Food Regulation (EC) No. 178/2002. The use of these terms as synonyms or their interchange is a recurrent issue in the area of food safety, despite awareness-raising messages sent by EFSA (European Food Safety Authority) and other interested entities. A quick screening of the EU's food regulations revealed several inconsistencies. Hence, it was considered necessary to further investigate if regulations could act as a source for this problem. A software tool was developed to support the detection and listing of inconsistent translations of "hazard" and "risk" in certain EU food regulations. Subsequently, native-speaking experts working in food safety from each EU country were asked to provide their individual scientific opinion on the prepared list. All data were statistically analysed after applying numerical scores (1-5) describing different levels of consistency. Results showed that the most common problem was the interchange of "hazard" with "risk" and vice versa. This lack of consistency can create confusion that can further translate into misjudgments at food risk assessment and communication levels.

The ultra-wideband near-infrared luminescence properties and applications of K2SrGe8O18:Cr3+ phosphor

The near-infrared (NIR) light sources are fascinating in real-time nondestructive examination applications. Given that chemical bonds in organic substances (such as C–H, O–H and N–H) have extensive absorption and reflection of light in the NIR region, the emission spectrum of the NIR light sources should be as broad as possible. In this work, ultra-wideband K2SrGe8O18 (KSGO):Cr3+ NIR-emitting phosphors with a 650–1200 nm emission span are developed. Structural analysis combined with electron paramagnetic resonance (EPR), photoluminescence (PL) spectra, time-resolved spectrum (TRES) and temperature-dependent PL spectra confirm that the super broadband emission with full width at half-maximum (FWHM) of 214 nm originates from the double Cr3+ luminescence centers occupying different [GeO6] octahedra. Li+ ion as charge compensator is introduced to balance the negative charge induced by the un-equivalent replacement of Cr3+ for Ge4+, and the PL intensity and thermal stability are greatly enhanced. The NIR phosphor-converted luminescent diodes (pc-LEDs) prepared by combining optimized KSGO:0.10Cr3+, 0.07Li+ samples with 460 nm LED chips demonstrate their application in night vision. The measured absorption spectra of hemoglobin, water, ethyl alcohol and peanut oil illuminated by the as-prepared KSGO:0.10Cr3+, 0.07Li+ phosphors indicate nondestructive analysis in the areas of food safety.

Direct phoxim sensing based on fluorescent metal-organic framework of Nu-1000 induced FRET

To control and on-site evaluate the contamination of organophosphorus pesticides, one direct sensing approach based on spontaneous fluorescence resonance energy transfer (FRET) was developed in this study. The luminescent metal-organic frameworks (LMOFs), a novel achievement of MOFs, could provide adjustable adsorption capacity and fluorescence index to scientific analysis was first employed to evaluate phoxim molecules in vegetables and fruits. Through the π-π recognition and FRET sensing between phoxim molecules and skeleton of Nu-1000 LMOFs probes, an ultra-low detection limit of 1.65 pg/L in the range of 5×10−7 to 5×10−3 mg/mL (R2=0.998) was achieved in the presence of phoxim. Such simple and accurate LMOFs- FRET-based sensing strategy could offer valuable reference for developing sensitive FRET sensors and/or on-site evaluation approaches in the areas of food quality control and food safety.