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Emerging Applications of Nanobiosensors in Pathogen Detection in Water and Food Texto completo
2023
Hiram Martin Valenzuela-Amaro | Alberto Aguayo-Acosta | Edgar Ricardo Meléndez-Sánchez | Orlando de la Rosa | Perla Guadalupe Vázquez-Ortega | Mariel Araceli Oyervides-Muñoz | Juan Eduardo Sosa-Hernández | Roberto Parra-Saldívar
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 <i>Salmonella</i>, Shiga-toxin producer <i>Escherichia coli</i>, <i>Campylobacter</i>, and <i>Listeria monocytogenes</i> are considered to be high-concern pathogens. High-concern waterborne pathogens are <i>Vibrio cholerae</i>, leptospirosis, <i>Schistosoma mansoni,</i> and <i>Schistosima japonicum</i>, 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.
Mostrar más [+] Menos [-]A multi-level approach to the energy-water-food nexus: From molecule to governance Texto completo
2023
Eric C. Okonkwo | Sarah Namany | Jamileh Fouladi | Ismail W. Almanassra | Farhat Mahmood | Tareq Al-Ansari
The energy-water-food (EWF) nexus is an approach to resource management that highlights the inextricable relationship that exists among three essential resources. The EWF nexus is aimed at fostering interlinkages, limiting trade-offs and exploiting synergies that exist amongst these resources. Adopting the nexus approach is key to sustainable development, as it can alleviate resource insecurities and harness collaboration between sectors. Several EWF nexus-related studies have exhaustively analysed the different levels of decision-making within the nexus. However, these studies have failed to account for the multi-level relationship that exists among the different levels of the nexus, as most have adopted a level-based approach. This review study presents a novel multi-level approach to addressing the EWF nexus-related challenges. The study analyses the multiple levels that exist within the EWF nexus. The three levels identified are the molecule, process, and governance levels. The study goes on to show how communication amongst all three levels not only impacts the performance of the system but is crucial for decision-making as the three stages are intrinsically related such that the decisions at one level directly influences the others. The study starts by reviewing the various molecular-level changes that can be made in each of the EWF resources to enhance their performance. Then a review of the set of modelling and analytical tools that have been applied to the process and governance levels are presented. Finally, a novel decision-making pyramid integrating all three levels is presented and discussed using the case of a greenhouse food production system.
Mostrar más [+] Menos [-]An integrated electrolysis – electrospray – ionization antimicrobial platform using Engineered Water Nanostructures (EWNS) for food safety applications Texto completo
2018
Vaze, Nachiket | Jiang, Yi | Mena, Lucas | Zhang, Yipei | Bello, Dhimiter | Leonard, Stephen S. | Morris, Anna M. | Eleftheriadou, Mary | Pyrgiotakis, Georgios | Demokritou, Philip
Engineered water nanostructures (EWNS) synthesized utilizing electrospray and ionization of water, have been, recently, shown to be an effective, green, antimicrobial platform for surface and air disinfection, where reactive oxygen species (ROS), generated and encapsulated within the particles during synthesis, were found to be the main inactivation mechanism. Herein, the antimicrobial potency of the EWNS was further enhanced by integrating electrolysis, electrospray and ionization of de-ionized water in the EWNS synthesis process. Detailed physicochemical characterization of these enhanced EWNS (eEWNS) was performed using state-of-the-art analytical methods and has shown that, while both size and charge remain similar to the EWNS (mean diameter of 13 nm and charge of 13 electrons), they possess a three times higher ROS content. The increase of the ROS content as a result of the addition of the electrolysis step before electrospray and ionization led to an increased antimicrobial ability as verified by E. coli inactivation studies using stainless steel coupons. It was shown that a 45-min exposure to eEWNS resulted in a 4-log reduction as opposed to a 1.9-log reduction when exposed to EWNS. In addition, the eEWNS were assessed for their potency to inactivate natural microbiota (total viable and yeast and mold counts), as well as, inoculated E. coli on the surface of fresh organic blackberries. The results showed a 97% (1.5-log) inactivation of the total viable count, a 99% (2-log) reduction in the yeast and mold count and a 2.5-log reduction of the inoculated E. coli after 45 min of exposure, without any visual changes to the fruit. This enhanced antimicrobial activity further underpins the EWNS platform as an effective, dry and chemical free approach suitable for a variety of food safety applications and could be ideal for delicate fresh produce that cannot withstand the classical, wet disinfection treatments.
Mostrar más [+] Menos [-]Use of molecular imprinted polymers as sensitive/selective luminescent sensing probes for pesticides/herbicides in water and food samples Texto completo
2022
Kumar, Vanish | Kim, Ki Hyun
As non-biological molecules, molecular imprinted polymers (MIPs) can be made as antibody mimics for the development of luminescence sensors for various targets. The combination of MIPs with nanomaterials is further recognized as a useful option to improve the sensitivity of luminescence sensors. In this work, the recent progresses made in the fabrication of fluorescence, phosphorescence, chemiluminescence, and electrochemiluminescence sensors based on such combination have been reviewed with emphasis on the detection of pesticides/herbicides. Accordingly, the materials that are most feasible for the detection of such targets are recommended based on the MIP technologies.
Mostrar más [+] Menos [-]Simultaneously speciation of mercury in water, human blood and food samples based on pyrrolic and pyridinic nitrogen doped porous graphene nanostructure Texto completo
2023
Shirkhanloo, Hamid | Habibnia, Mohsen | Rashidi, Alimorad | Faghihi Zarandi, Ali | Dehghani Mobarake, Mostafa
A rapid and efficient method based on a novel nitrogen-doped porous graphene nanostructure (NDPG) was used for the speciation of mercury in water and human blood samples by the CV-AAS. The mixture of the NDPG, ionic liquid, and acetone was rapidly injected into the human blood, water, and food samples for mercury separation by the cloud point assisted dispersive ionic liquid-micro solid-phase extraction (CPA-DIL-μ-SPE) at pH 7.5. The UV-microwave accessory converted the organic mercury (R-Hg) to inorganic mercury, and total mercury (TM) was determined. Finally, the organic mercury was calculated by subtracting the inorganic and entire mercury contents. By optimizing, the linear range, LOD, and enrichment factor were obtained (0.01–6.80 µg/L; 0.005–3.60 µg/L), (2.6 ng/L; 1.2 ng/L) and (9.8; 20.2) for the mercury species in human blood and water/food samples, respectively (Mean of RSD < 1.9 %). The CRM samples obtained the validation of the procedure.
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