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Adulteration of meat is a global issue, necessitating rapid, inexpensive, and simple on-site testing methods. Therefore, the present study aimed to develop a one-minute toothpick-based DNA extraction method, a handheld microfluidic chip, and a smartphone-controlled portable analyzer for detecting multiple meat adulterations. A toothpick was inserted into the meat to promote DNA release and adsorption. Furthermore, a handheld microfluidic chip was designed for DNA elution on toothpicks and fluid distribution. Finally, a smartphone-actuated portable analyzer was developed to function as a heater, signal detector, and result reader. The portable device comprises a microcontroller, a fluorescence detection module, a step scanning unit, and a heating module. The proposed device is portable, and the app is user-friendly. This simple design, easy operation, and fast-response system could rapidly detect as little as 1% of simulated adulterated samples (following UK standards) within 40 min at a cost of less than USD 1 per test.
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BACKGROUND: Mastitis, a pervasive and detrimental disease in dairy farming, poses a significant challenge to the global dairy industry. Monitoring the milk somatic cell count (SCC) is vital for assessing the incidence of mastitis and the quality of raw cow's milk. However, existing SCC detection methods typically require large-scale instruments and specialized operators, limiting their application in resource-constrained settings such as dairy farms and small-scale labs. To address these limitations, this study introduces a novel, smartphone-based, on-site SCC testing method that leverages smartphone capabilities for milk somatic cell identification and enumeration, offering a portable and user-friendly testing platform. RESULTS: The central findings of our study demonstrate the effectiveness of the proposed method for counting milk somatic cells. Its on-site applicability, facilitated by the microfluidic chip, optical system, and smartphone integration, heralds a paradigm shift in point-of-care testing (POCT) for dairy farms and smaller laboratories. This approach bypasses complex processing and presents a user-friendly solution for real-time SCC monitoring in resource-limited settings. This device boasts several unique features: small size, low cost (<$1,000 total manufacturing cost and <$1 per test), and high accuracy. Remarkably, it delivers test results within just 2 min. Actual-sample testing confirmed its consistency with results from the commercial Bentley FTS/FCM cytometer, affirming the reliability of the proposed method. Overall, these results underscore the potential for transformative change in dairy farm management and laboratory testing practices. SIGNIFICANCE: In summary, this study concludes that the proposed smartphone-based method significantly contributes to the accessibility and ease of SCC testing in resource-limited environments. By fostering the use of POCT technology in food safety control, particularly in the dairy industry, this innovative approach has the potential to revolutionize the monitoring and management of mastitis, ultimately benefiting the global dairy sector.
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Mastitis , Leche , Humanos , Animales , Femenino , Bovinos , Sistemas de Atención de Punto , Reproducibilidad de los Resultados , Teléfono Inteligente , Recuento de Células/métodos , Industria Lechera/métodos , Mastitis/veterinariaRESUMEN
With the globalization and complexity of the food supply chain, the market is becoming increasingly competitive and food fraudulent activities are intensifying. The current state of food detection faced two primary challenges. Firstly, existing testing methods were predominantly laboratory-based, requiring complex procedures and precision instruments. Secondly, there was a lack of accurate and efficient quantitative detection methods. Taking cow's milk as an example, this study introduced a novel method for nucleic acid quantification in dairy products, based on lateral flow strips (LFS). The core idea of this method is to design single-stranded DNA (ssDNA) probes to hybridize with mitochondrial genes, which are abundant, stable, and species-specific in dairy products, as detection targets. Drawing inspiration from the principles of nucleic acid amplification, this research innovatively established a new DNA hybridization method, named LAMP-Like Hybridization (HybLAMP-Like). Leveraging the denaturation and DNA polymerization functions of the bst enzyme, efficient binding of the probe and template strand was achieved. This method eliminated the need for nucleic acid amplification, simplifying the procedure and mitigating aerosol contamination, thereby ensuring the accuracy of the detection results. The method exhibited exceptional sensitivity, capable of detecting extremely low to 12.5 ng in visual inspection and 3.125 ng when using a reader. In terms of practicality, it could achieve visual detection of cow's milk content as low as 1% in adulterated dairy products. When combined with a portable LFS reader, it also enabled precise quantitative analysis of milk adulteration.
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Técnicas Biosensibles , Leche , Animales , Técnicas Biosensibles/métodos , ADN/genética , ADN/química , Técnicas de Amplificación de Ácido Nucleico/métodos , ADN de Cadena Simple , GenómicaRESUMEN
Monitoring and evaluating food quality, especially meat quality, has received a growing interest to ensure human health and decrease waste of raw materials. Standard analytical approaches used for meat spoilage assessment suffer from time consumption, being labor-intensive, operation complexity, and destructiveness. To overcome shortfalls of these traditional methods and monitor spoilage microorganisms or related metabolites of meat products across the supply chain, emerging analysis devices/systems with higher sensitivity, better portability, on-line/in-line, non-destructive and cost-effective property are urgently needed. Herein, we first overview the basic concepts, causes, and critical monitoring indicators associated with meat spoilage. Then, the conventional detection methods for meat spoilage are outlined objectively in their strengths and weaknesses. In addition, we place the focus on the recent research advances of emerging non-destructive devices and systems for assessing meat spoilage. These novel strategies demonstrate their powerful potential in the real-time evaluation of meat spoilage.
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Calidad de los Alimentos , Carne , Humanos , Carne/análisisRESUMEN
Exosomes are promising new biomarkers for colorectal cancer (CRC) diagnosis, due to their rich biological fingerprints and high level of stability. However, the accurate detection of exosomes with specific surface receptors is limited to clinical application. Herein, an exosome enrichment platform on a 3D porous sponge microfluidic chip is constructed and the exosome capture efficiency of this chip is ≈90%. Also, deep mass spectrometry analysis followed by multi-level expression screenings revealed a CRC-specific exosome membrane protein (SORL1). A method of SORL1 detection by specific quantum dot labeling is further designed and the ensemble classification system is established by extracting features from 64-patched fluorescence images. Importantly, the area under the curve (AUC) using this system is 0.99, which is significantly higher (p < 0.001) than that using a conventional biomarker (carcinoembryonic antigen (CEA), AUC of 0.71). The above system showed similar diagnostic performance, dealing with early-stage CRC, young CRC, and CEA-negative CRC patients.
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Neoplasias Colorrectales , Exosomas , Humanos , Antígeno Carcinoembrionario , Microfluídica/métodos , Biomarcadores de Tumor/metabolismo , Exosomas/metabolismo , Porosidad , Detección Precoz del Cáncer , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/metabolismo , Proteínas Relacionadas con Receptor de LDL/metabolismo , Proteínas de Transporte de Membrana/metabolismoRESUMEN
With the rapid development of modern society, the energy crisis has become a global concern. Solar energy is a good replacement because it is green, unlimited and environment-friendly. Inspired by natural photosynthesis, artificial photosynthesis was developed to convert solar energy to chemical energy by a photocatalyst system. For better utilizing solar energy and improving the conversion efficiency, the design of photoreactors is crucial for the improvement of photocatalysis efficiency. However, most of the reported microreactors hardly satisfy the demands for low cost, easy fabrication, high transparency, being evaporation-proof, ease of scaling up, high surface-to-volume ratio, and photocatalyst immobilization. In this paper, we developed a facile method to build a fully immobilized microreactor (FIM) and a controllable partially immobilized microreactor (PIM), both of which satisfy all the demands mentioned above. In the FIM, the regeneration rate of a coenzyme (nicotinamide adenine dinucleotide, NADH) reached 82.20% in 40 min. Considering the NADH regeneration rate per unit/coating angle of photocatalysts in circular microreactors, the PIM performed much better than the FIM, proving that our partial coating method is a significant and useful improvement. Also, the bioactivity of NADH toward enzyme catalysis was demonstrated by glutamate dehydrogenase-catalyzed synthesis of L-glutamate, and the conversion of α-ketoglutarate reached 99.92%. To test the practicality of the microreactor in a real environment, we performed a test under solar light, achieving a good result of 74.92% in 60 min. Thus, this efficient and versatile microfluidic platform may have good potential for photocatalytic synthesis of versatile valuable products in the future.
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Ácido Glutámico , NAD , Catálisis , Coenzimas , NAD/metabolismo , Fotosíntesis , RegeneraciónRESUMEN
Exosomes, a nano-sized subtype of extracellular vesicles secreted from almost all living cells, are capable of transferring cell-specific constituents of the source cell to the recipient cell. Cumulative evidence has revealed exosomes play an irreplaceable role in prognostic, diagnostic, and even therapeutic aspects. A method that can efficiently provide intact and pure exosomes samples is the first step to both exosome-based liquid biopsies and therapeutics. Unfortunately, common exosomal separation techniques suffer from operation complexity, time consumption, large sample volumes and low purity, posing significant challenges for exosomal downstream analysis. Efficient, simple, and affordable methods to isolate exosomes are crucial to carrying out relevant researches. In the last decade, emerging technologies, especially microfluidic chips, have proposed superior strategies for exosome isolation and exhibited fascinating performances. While many excellent reviews have overviewed various methods, a compressive review including updated/improved methods for exosomal isolation is indispensable. Herein, we first overview exosomal properties, biogenesis, contents, and functions. Then, we briefly outline the conventional technologies and discuss the challenges of clinical applications of these technologies. Finally, we review emerging exosomal isolation strategies and large-scale GMP production of engineered exosomes to open up future perspectives of next-generation Exo-devices for cancer diagnosis and treatment.
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Physico-chemical properties and molecular structure of starches from three cultivars (Dog hoof, Mein, and KS01) of taro tubers planted in summer, winter, and spring were investigated. The effects of the planting season on the physico-chemical properties and the molecular structure of starch were determined, and the relations between the physico-chemical properties and the molecular structure of starch are discussed. Results indicate that taro starches from tubers planted in summer had the largest granule size, a low uniformity of gelatinization, and a high tendency to swell and collapse when heated in water. Taro starch planted in summer also showed an elasticity during gelatinization that was higher than that of starches planted in the other seasons. In addition to the planting season and the variety, rheological and pasting properties of taro starches studied are influenced not only by the amylose content but also by the chain-length distribution of amylopectin, whereas swelling power and solubility only depend on the amylose content of starch. Taro starch with relatively high amylose content, high short-to-long-chain ratio, and long average chain length of long-chain fraction of amylopectin displayed high elasticity and strong gel during heating.