Food Samples Research Articles

Vortex-assisted dispersive solid-phase microextraction of manganese in food samples by using newly synthesized biodegradable poly (3-hydroxy butyrate) diethanol amine

A newly synthesized biodegradable polyhydroxy butyrate diethanol amin (PHB-DEA) was used as adsorbent for vortex assisted dispersive solid phase microextraction (VA-dSPµE) of manganese in food samples. The different parameters were optimized such as pH, amount of adsorbent, time, desorption solvents and time and also number of reuses. After the sample preparation step, the determination of manganese from food samples was carried out using flame atomic absorption spectrometry. The present developed method showed good LOD value 0.15ngmL-1 and LOQ 0.5ngmL-1. The 0.5-300ngmL-1 linearity range was found and enhancement factor was 182. The inter-day RSD% was 2.2-4.1 and intra-day RSD% was 2.8-5.2. The recovery of manganese was found in the 95-98% range. The factorial design was employed such as response surface plots, pareto chart, residual plots and ANOVA was applied to estimate the significant level of the model using central composite design (CCD). The developed VA-dSPµE procedure was successfully implemented to determine manganese in food samples.

Pyrochlore stannate synthesis: Unlocking temperature's influence on electrochemical detection of caffeic acid in food samples

Pyrochlore stannate synthesis: Unlocking temperature's influence on electrochemical detection of caffeic acid in food samples

Dual-mode sensing with L-phenylalanine-stabilized copper nanoparticles: Real-time detection of Fe3+ and pH monitoring

Water-soluble copper nanoparticles stabilized with L-Phenylalanine (L-PCuNPs) were synthesized and characterized for dual sensing of Fe3+ ions and pH levels. These nanoparticles exhibited green fluorescence at 486 nm, which was quenched by Fe3+ ions, resulting in a color shift from colorless to yellow. Additionally, L-PCuNPs showed pH responsiveness, with increased fluorescence intensity as the pH shifted from acidic to basic. Their effectiveness was further validated through analysis of environmental, biological, and food samples, demonstrating their practical utility across diverse real-world applications.

Whole genome sequencing reveals circulation of potentially virulent Listeria innocua strains with novel genomic features in cattle farm environments in Dhaka, Bangladesh.

Through the last decade, Listeria spp. has been detected in food and environmental samples in Bangladesh. However, the genomic information of this bacterium that prevails in the country remains scarce. This study analyzed the complete genome sequences of two Listeria spp. isolates obtained from cow dung and their drinking water collected from a cattle farm in Dhaka, Bangladesh. Both the isolates were identified as Listeria innocua, which shared almost identical genomic features. The genome sequences demonstrated the presence of 13 virulence genes associated with invasion (iap/cwhA, gtcA, and lpeA), surface protein anchoring (lspA), adherence (fbpA, and lap), intracellular survival (lplA1, and prsA2), peptidoglycan modification (oatA, and pdgA), and heat stress (clpC, clpE, and clpP). Additionally, the gene fosX, conferring resistance to fosfomycin, and two copper resistance-associated genes, copC and csoR, were identified in both. The genome sequences also revealed two plasmid replicons, rep25 and rep32, along with three insertion sequences [ISLmo3 (CP022021), ISLmo7 (CP006611), ISS1N (M37395)]. Notably, a composite transposon [CN_8789_ISS1N (M37395)], was detected in both L. innocua isolates, representing the first documented occurrence of this particular composite transposon in any reported Listeria species. Furthermore, the genomes contained four prophage regions [Listeria phage LP-030-2 (NC_021539), Listeria phage vB_LmoS_188 (NC_028871), Listeria phage A118 (NC_003216) and Escherichia phage RCS47 (NC_042128)]. Two CRISPR arrays were also identified, one belonging to the family type II-A. Multilocus Sequence Typing (MLST) analysis classified the L. innocua isolates of the same sequence type, ST-637. Single nucleotide polymorphism (SNP) analysis uncovered the presence of 231-340 SNPs between the L. innocua isolates and their closely related global lineage. In contrast, only 42 SNPs were identified between the two isolates, suggesting a potential transmission of L. innocua between cow dung and cattle farm water. The presence of L. innocua isolates harboring virulence genes associated with ruminant infection in the cattle farm environment of Bangladesh raises significant concerns about the potential presence of other human and animal pathogens. This poses a serious threat to the cattle farming industry. Additionally, the genomic analysis of the L. innocua isolates enhances our understanding of the evolutionary dynamics of Listeria species.

Visual monitoring of hydrazine in food and environmental samples by wearable probe

Hydrazine is a poisonous compound that has been widely applied in the agricultural and chemical industry, leading to serious environmental pollution. Thus, the detection of hydrazine remained extremely important for ensuring food safety and environmental protection. Considering the importance of hydrazine detection for human health, a novel colorimetric/fluorescent probe (TPB) for the detection of hydrazine in various samples has been developed. In the presence of hydrazine, TPB emits a blue emission band at 452nm with high sensitivity (limit of detection equal to 40nM), ultrafast detection (less than 10s), broad working pH range (6−10), and strong anti-interference capabilities. These excellent performances have been exploited to fabricate hydrogel-based sensing labels (test kits, cotton swabs, glass rods, and gloves), which allowed the detection of hydrazine traces in soil, earthworms, plant samples, and living cells. This work presents a novel sensing approach for future research, aiming to develop a novel fluorescent probe exploiting the ICT process for the detection of hydrazine.

Sustainable analytical approach for selective fluorescence sensing of sulfosulfuron using copper nanoclusters from Tinospora cordifolia leaves extract

In recent times, there has been a growing trend in utilizing medicinal plant extracts for the fabrication of fluorescent nanomaterials. In this work, Tinospora cordifolia-copper nanoclusters (T. cordifolia-CuNCs) were produced by employing Tinospora cordifolia (common name is “giloy”), a medicinal plant. A green chemistry approach was employed to generate blue fluorescent T. cordifolia-CuNCs, displaying λEm at 430 nm when λEx at 330 nm, which shows a good quantum yield (QY) of 26.67 %. Sulfosulfuron pesticide was able to quench the fluorescence intensity of T. cordifolia-CuNCs via a “turn-off” mechanism. It was noticed that T. cordifolia-CuNCs could be used for the detection of sulfosulfuron pesticide in the range of 0.025–90 µM with a detection limit of 6.52 nM. Furthermore, a cellulose-based paper strip sensor was created for thevisual detection of sulfosulfuron pesticide. Moreover, T. cordifolia-CuNCs-based fluorescence method was applied to quantify sulfosulfuron pesticide in apple, tomato, and rice samples, showing good recoveries, which demonstrates that this probe offers great potentiality for sensing of sulfosulfuron pesticide in food and environmental samples

Construction of rhodamine-based fluorescent sensor for fast, on-site quantitative detection of hazardous salicylic acid in practical sample analysis

Salicylic acid (SA) is widely used in food storage, preservatives, additives, healthcare, and the pharmaceutical industry. However, various poisoning symptoms are frequently reported upon ingestion of a large amount of SA. Therefore, discovering new tools for sensing SA with fast, simple, and portable performance is imperative. Herein, five rhodamine-based fluorescent sensors were constructed, and investigated their SA detection profiles. Probe 1 was excellent selective with a rapid response, highly sensitive (LOD = 2.5 μM), good interference resistance, and unaided eye recognition. The spray experiment and paper-based test strips indicating that probe 1 enables to the on-site and quantitatively detect SA on actual food surfaces by using a smartphone identifying the RGB values. The sensing performance was validated in soil samples, water, and various agricultural food samples. Overall, the constructed SA sensor can function as a promising, convenient, and affordable tool for point-of-care detection of SA in diversiform environmental samples.

Biogenic Amines: Catalysis, Quality, and Safety Aspects of Food Items Consumed in Saudi Arabia

Introduction: In this study, the identification and quantification of biogenic amines in 45 commonly consumed food samples in Saudi Arabia were carried out. The enzymes responsible for producing these biogenic amines include spermidine (SPD), putrescine (PUT), tryptamine (TRP), tyramine (TYR), and histamine (HIS), which are synthesized through organo-catalytic pathways. Method: The diverse range of samples analyzed encompassed various types of beef, pickle varieties, canned fish, vegetables, chicken varieties, spices, fruits, and salad ingredients. Sample preparation involved the use of dansyl chloride after aqueous extraction, followed by isolation and analysis using reversed-phase HPLC with a UV detector. In five beef samples, mean concentrations of SPD, PUT, TRP, HIS, and TYR were identified as 9.41, 8.98, 155.8, 100.8, and 304.2 mg kg-1, respectively. Canned fish samples exhibited mean concentrations of TRP, PUT, HIS, TYR, and SPD at 71.6, 3.88, 29.2, 2.56, and 2.02 mg kg-1, respectively. Result: Among five pickle samples, mean concentrations of TRP, PUT, HIS, TYR, and SPD were reported as 118.8, 39.12, 35.2, 27.2, and 2.56 mg kg-1, respectively. Chicken samples primarily contained TRP, HIS, and SPD as the identified biogenic amines, with mean concentrations of 87.2, 105.6, and 5.22 mg kg-1, respectively. Fruit samples generally exhibited low levels of all enzymes except for TRP. Conclusion: It was found that vegetables, seasonings, and salad ingredients either had undetectable or low quantities of biogenic amines.

Guardians of resistance and virulence: detection of mec, femA, Van, pvl, hlg and spa genes in methicillin and vancomycin-resistant Staphylococcus aureus from clinical and food samples in Southwestern Nigeria.

Staphylococcus aureus strains are highly virulent and associated with an eclectic range of severe nosocomial and community-acquired infections. This study assessed methicillin- and vancomycin-resistant Staphylococcus aureus (MRSA/VRSA) from clinical and ready-to-eat (RTE) food sources, screened for antibiotic resistance; and molecular determinants of antibiotic and virulence genes. Altogether, 465 clinical and RTE food samples were analyzed via conventional microbiological techniques and S. aureus identification was confirmed by nuc gene detection. Phenotypic screening for methicillin and vancomycin-resistance was by agar-screen cum micro-broth dilution respectively, while antibiotic susceptibility testing was done by the disc-diffusion technique. VanA/vanB/VanC1, femA, mecA/mecC; pvl/hlg and spa gene detection was via Polymerase chain reaction. Phenotypically, 211 Staphylococcal isolates were recovered, 138 (65.4%) of them carrying the nuc gene - all 138 (100.0%) were VRSA, while 59/138 (42.8%) were MRSA phenotypically. Overall, 114/138 (82.6%), 7/138 (5.1%), and 6/138 (4.3%) of isolates had the femA, mecA, and mecC genes, while van genes were detected in only 3 (2.2%) isolates, with virulence determinants pvl, hlg, and spa gene carriage in 8 (5.8%), 10 (7.2%), and 77 (55.8%) isolates respectively. In all, 11.6% carried resistance-associated genes, 55.8% carried virulence genes, and co-detection of resistance and virulence genes was observed in 12.3%. Overall, 96/138 (69.6%) were multidrug-resistant (MDR), while one strain was extremely drug-resistant (XDR). MAR Indices ≥ 0.2 was observed in 83.3% of isolates. This study highlights virulence levels of MRSA and VRSA circulating strains in Osogbo, contributing to their sustained surveillance, and improving available data for successive epidemiology investigations. This study also reports the occurrence of the mecC gene in S. aureus isolates from RTE foods and human samples in Southwestern Nigeria.

Prevalence and Antibiotic Susceptibility of Nontyphoidal Salmonella from Food-Animal Products in Bejaia, Algeria.

Nontyphoidal Salmonella presents a significant threat to animal and human health as a food-borne infectious agent. This study focused on the characterization of Salmonella isolates obtained from fresh animal products consumed in Bejaia, Algeria. In total, 495 beef products, 600 chicken products, and 355 dairy products were collected from retail outlets and slaughterhouses in the region. Out of the 1450 samples collected, a Salmonella positivity rate of 3.5% (51/1450) was observed. Traditional Algerian sausages exhibited the highest prevalence of Salmonella contamination (14.1%, 36/256). Fifteen different serotypes were identified, with S. Kentucky (n = 12), S. Anatum (n = 11), and S. Bredeney (n = 9) being the most prevalent. Antimicrobial susceptibility testing showed resistance to diverse antibiotics, particularly against tetracycline, ampicillin, nalidixic acid, and sulphonamides. Whole-genome sequencing conducted on 21 isolates enabled the comparison of phylogenetic links between isolates. We notably identified clones circulating across the region in different locations and food types, suggesting contamination at the early stages of the food chain (in the herd or slaughterhouses) that disseminated to numerous butcher shops in various cities. We also identified acquired antibiotic resistance genes and point mutations in the quinolone resistance-determining region genes, contributing to the observed resistance patterns. This study describes the genomic and phylogenetic characteristics of several Salmonella clones found in diverse food samples in Algeria. It suggests potential transmission dynamics that could better understand Salmonella's contamination routes.

Detection of micro- and nanoplastic particles in leafy green vegetables by SERS coupled with gold-silver core-shell nanoparticles.

Asensitive and accurate method has been developedfor detecting and quantifying polystyrene (PS) and polyethylene (PE) in food samples using surface-enhanced Raman spectroscopy (SERS) with a simple preparation process. Themethod is designed to effectively detect and quantify mixtures of these polymers in varying ratios within the food matrix. By employing gold-silver core-shell nanoparticles (Au@Ag NPs) as the enhancing substrate, the SERS method demonstrated superior sensitivity in detecting trace amounts of micro- and nanoplastic particles (MNPs). For 1-µm PS microparticles, the limit of detection (LOD) values range from 12 to 50 mg/L or mg/kg in water, spinach, and kale, while for 100-nm PS nanoparticles, the LOD values range from 18 to 47 mg/L or mg/kg. For 1-µm PE microparticles, the LOD values range from 173 to 416 mg/L or mg/kg in the same matrices, whereas for 65-nm PE nanoparticles, the values range from 446 to 744 mg/L or mg/kg. The mixtures of PS and PE in varying ratios were also tested, with both plastics detectable even at trace levels, emphasizing the method's precision in detecting plastic contaminants. These findings highlight the potential of SERS as a powerful tool for monitoring MNP contamination in food products by detecting both individual plastics and their mixtures, enabling precise quantification of contamination and contributing to improved food safety.

Quantitative analysis of seven commonly used synthetic food color additives by HPLC-PDA

Sixteen color additives (tar colors) were detected in 128 food samples (macarons, meringue cookies, and coque macarons) using HPLC with a photodiode array detector at 420 nm, 520 nm, and 620 nm for the yellow, red, and blue and green color types, respectively. The tar color recovery rates ranged from 81.3 to 95.6%, and their limits of detection (LOD) and quantification (LOQ) were 0.001–0.049 mg/kg and 0.004–0.147 mg/kg, respectively. Seven tar colors (Y4, Y5, R3, R40, R102, B1, and B2) were detected in 129 samples. All the samples did not contain nine tar colors (R2, G3, Azo, R106, QY, ORII, BBN, PBV, and GS). The quantity of tar colors (Y4, Y5, R40, and B1) in 15 samples exceeded the Korean Ministry of Food and Drug Safety (MFDS) standard. Ninety samples (70%) used a mixture of two or more tar colors, and the amount used was 11.0–1643.3 mg/kg. The quantity of combined tar colors in 15 samples exceeded 300 mg/kg. Through these findings, this study aims to contribute to the development of safer and more reliable desserts containing tar colors, by enhancing safety measures and ensuring improved quality control for consumer protection.

Peroxidase-like Nanoparticles of Noble Metals Stimulate Increasing Sensitivity of Flavocytochrome b2-Based L-Lactate Biosensors.

We report the development of amperometric biosensors (ABSs) employing flavocytochrome b2 (Fcb2) coupled with nanoparticles (NPs) of noble metals on graphite electrode (GE) surfaces. Each NPs/GE configuration was evaluated for its ability to decompose hydrogen peroxide (H2O2), mimicking peroxidase (PO) activity. The most effective nanoPO (nPO) was selected for developing ABSs targeting L-lactate. Consequently, several Fcb2/nPO-based ABSs with enhanced sensitivity to L-lactate were developed, demonstrating mediated ET between Fcb2 and the GE surface. The positive effect of noble metal NPs on Fcb2-based sensor sensitivity may be explained by the synergy between their dual roles as both PO mimetics and electron transfer mediators. Furthermore, our findings provide preliminary data that may prompt a re-evaluation of the mechanism of L-lactate oxidation in Fcb2-mediated catalysis. Previously, it was believed that L-lactate oxidation via Fcb2 catalysis did not produce H2O2, unlike catalysis via L-lactate oxidase. Our initial research revealed that the inclusion of nPO in Fcb2-based ABSs significantly increased their sensitivity. Employing other PO mimetics in ABSs for L-lactate yielded similar results, reinforcing our hypothesis that trace amounts of H2O2 may be generated as a transient intermediate in this reaction. The presence of nPO enhances the L-lactate oxidation rate through H2O2 utilization, leading to signal amplification and heightened bioelectrode sensitivity. The proposed ABSs have been successfully tested on blood serum and fermented food samples, showing their promise for L-lactate monitoring in medicine and the food industry.

Fluorescence sensor array for highly sensitive pattern recognition of biothiols in food based on tricolor upconversion luminescence metal-organic frameworks

Fluorescence nanomaterial sensors have exhibited excellent application potential in biothiols analyses. The fluorescence sensor arrays constructed from upconversion luminescence metal-organic frameworks nanocomposites (LMOFs) can provide impressive discrimination and exquisite fingerprinting capabilities for extremely similar analytes. Herein, an upconversion fluorescence sensor array based on LMOFs featuring UiO-type metal-organic frameworks-functionalized lanthanide-doped upconversion nanoparticles was proposed, wherein Cu2+ can make the fluorescence quenching of LMOFs and preferentially bind biothiols to recover fluorescence in different degrees forming unique fingerprinting. The fluorescence sensor array displayed an excellent pattern recognition for five biothiols (glutathione, homocysteine, N-acetylcysteine, and L/D-cysteine) even at 50 µM by linear discriminant analysis, and the discernment for the enantiomers of L/D-cysteine, as well as the accurate identification (90.0% accuracy) of biothiols in food samples (tea beverage and white wine). Such fluorescence sensor array might provide a simple and efficient detection method for biothiols.

Nutrients Composition of Acha Base Complementary Food Supplemented with Soybean and Sweet Potato Flour

Poor complementary food and feeding had been shown to increase the morbidity and mortality among under-five children in developing countries in which Nigeria is not exempted. This study aimed at evaluating the Nutrients Composition of Acha -Based complementary food supplemented with soybean and sweet potato flour. Raw materials used for the formulated of the complementary were purchased from Erekesan market in Akure Local Government Area of Ondo State. Five (5) samples were formulated in different ratios of Acha (100:70:60:50:40), Soyabean (20:25:30:35) and Orange flesh sweet potato (10:15:20:25). Samples were subjected to chemical and instrumental analysis in line with standard method. The data obtained were statistically analyzed using ANOVA to test for the significant difference among means (P<0.05) using Statistical Package for Social Science (SPSS version 22). Finding shows that Moisture, crude fibre, and carbohydrate was significantly (p<0.05) higher in sample Awhile, Sample E was significantly (p<0.05) higher protein (18.42%) and fat (12.40%) compared to other formulated samples. The Moisture, crude fibre, and CHO was significantly (p<0.05) decreases with decreased in the quantity of Acha use in the formulation of the CFs while crude fat, Ash and protein increases with increase in the quantity of soybean incorporated in the formulations. Sample E is significantly (P<0.05) higher in vitamin B1, B3 and B9 compared with sample A. vitamin B1, B3 and B9 increases with increase in the quantity of soybean and OFSP. All the samples have appreciable amount of sodium, calcium, phosphorus, magnesium and potassium but, zinc and iron was low in the entire sample. Sample E was exceptional in all the minerals but significantly (p<0.05) lower in Zinc and iron. The mean sensory scores revealed that sample C was different in after taste, flavour, mouth feel, colour and overall acceptability. The mean scores increase with increase in the proportion of soybean and potato in the formulated complementary food samples in terms of all the sensory attributes tested. The scores showed that sample C had the highest acceptability by the panelists. The complementary foods had improved nutrients that can support optimal nutrition of undernourished children and other older people.

Highly sensitive SERS-based lateral flow immunoassay of fipronil using bimetallic Au@Ag@Ag nanorods.

Abimetallic core-shell-shell nanorods structure with gap-embedded Raman reporter 5,5'-dithio-bis-(2-nitrobenzoic acid) (DTNB) was developed and applied as a SERS-active nanotag in surface-enhanced Raman scatteringlateral flow immunoassay (SERS-LFIA) of theinsecticide fipronil. Due to the strong SERS signal of the AuDTNB@AgDTNB@AgNRods, fipronil is detected with extremely low detection limit of 4.6pg/mL. To the best of our knowledge, the proposed technique is the first SERS-LFIA of fipronil, proven to be effective in the selective determination of the target analyte and capable of detecting fipronil in a matrix of food samples (cucumber and apple juice) with recoveries of 97.0-117.0%. Moreover, the applied functionalization of the SERS nanotag with anti-species antibodies has provided a versatile immunoprobe that could improve performance of different LFIAs.

Formulation and Evaluation of Weaning Foods Prepared from Multigrain Flour and Powdered Milk

Aims: Children after 6 months need to shift from breast milk to weaning food. The present study aims to develop low cost nutritious weaning foods to fulfil the increased nutritional requirements during this phase of growth. Study Design: The present study involved development of three different samples of low cost weaning foods prepared with multigrain flour (combination of rice flour, wheat flour and gram flour in the ratio of 2:1:0.5) mixed with milk powder (5%, 7.5% and 10% of the total flour mixture). Sensory, physicochemical and cost analyses were performed for the samples. Place and Duration of Study: University Polytechnic (Boys), Aligarh Muslim University, Aligarh, Uttar Pradesh, between January 2016 and July 2016. Methodology: Sensory evaluation was done on a 9 point hedonic scale after preparing the samples for consumption by adding either water or milk. Physicochemical properties of the developed samples such as moisture content, ash content and protein content were assessed during storage at room temperature (25-32˚C) for 2 months in airtight laminated aluminium film packing material. Results: In sensory of samples prepared with water, sample 3 was found to be the most preferred sample while in case of samples prepared with milk, sample 1 was found to be the best in sensory quality. All the developed weaning food samples were found to be stable during 50 days of storage. Moisture content, Protein content and Ash content of the samples ranged from 4.84 to 10.38%, 13.23 and 16.29% and 1.22 to 1.54% respectively. Samples with more milk powder showed higher protein content and fat content. Conclusion: The prepared weaning food samples had comparable physicochemical and sensory characteristics and lower cost than the commercially available weaning foods. They will be helpful in fulfilling the nutritional requirement of the vulnerable sections of society including middle-income groups (MIG) and low-income groups (LIG) consumers and overcoming malnutrition.

Quantum dot-based biomimetic fluorescence immunoassays for enrofloxacin detection in animal-derived foods.

Long-term consumption of foods with excessive enrofloxacin (ENRO) residues may cause the accumulation of ENRO in the human body, thus damaging human health. In this study, quantum dot-based biomimetic fluorescence immunoassays were used for enrofloxacin detection in food of animal origin. Under the most suitable conditions, the detection limit (IC15) of the method in standard solution was 0.13 ± 0.02 ng L-1 and the sensitivity (IC50) was 0.13 ± 0.18 μg L-1. The recoveries for ENRO from four fortified food samples, including chicken, eggs, shrimp, and milk, ranged from 85.74% to 114.19% and the coefficients of variation were 0.01-18.09%. The established method shows good agreement with the results obtained using commercial ELISA kits, with a correlation coefficient of 0.997. The proposed method shows the advantages of high sensitivity, specificity and wide detection range. It can be used as an alternative method for the rapid and sensitive detection of ENRO in food of animal origin.

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.

Conducting polymer functionalized Cu-metal organic framework-based electrochemical immunosensor for rapid and sensitive quantitation of Escherichia coli O157:H7.

Escherichia coli (E. coli) O157:H7 is an important food-borne pathogen that can cause hemorrhagic diarrhea and enteritis in humans and animals. Realizing the rapid quantitation of E. coli O157:H7 is of great significance for the guarantee of food safety and disease control. In this study, an electrochemical immunosensing technique based on a functionalized composite of Cu-metal organic framework (Cu-MOF) and poly (3,4-ethylenedioxythiophene)-poly (styrenesulfonate) (PEDOT:PSS) is developed, achieving rapid and sensitive quantitation of E. coli O157:H7 in food and clinical feces samples. The organic functionalization of Cu-MOF significantly improves the interface conductivity to facilitate electron transfer and provides the sulfonic groups (-SO3H) to conjugate bio-recognizing elements for target determination. The immunosensor delivers a linear detection range of 3 × 102 ~ 3 × 108cfu/mL, a low limit of detection (LOD) of 7.4cfu/mL, and a short analysistime of 40min. In addition, it does not show any cross-reactivity with other common pathogens and exhibits high repeatability with relative standard deviations (RSDs) all lower than 2.09%, providing a promising approach for warranting food safety and control of E. coli O157:H7 disease.