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Fully integrated devices that enable full functioning execution without or with minimum external accessories or equipment are deemed to be one of the most desirable and ultimate objectives for modern device design and construction. Escherichia coli O157:H7 (E. coli O157:H7) is often linked to outbreaks caused by contaminated water and food. However, the sensors that are currently used for point-of-care E. coli O157:H7 (E. coli O157:H7) detection are often large and cumbersome. Herein, we demonstrate the first example of a handheld and pump-free fully integrated electrochemical sensing platform with the capability to point-of-care test E. coli O157:H7 in the actual samples of E. coli O157:H7-spiked tap water and E. coli O157:H7-spiked watermelon juice. This platform was made possible by overcoming major engineering challenges in the seamless integration of a microfluidic module for pump-free liquid sample collection and transportation, a sensing module for efficient E. coli O157:H7 testing, and an electronic module for automatically converting and wirelessly transmitting signals into a single and compact electrochemical sensing platform that retains its inimitable stand-alone, handheld, pump-free, and cost-effective feature. Although our primary emphasis in this study is on detecting E. coli O157:H7, this pump-free fully integrated handheld electrochemical sensing platform may also be used to monitor other pathogens in food and water by including specific antipathogen antibodies.
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Escherichia coli O157 , Anticuerpos , Pruebas en el Punto de Atención , Sistemas de Atención de Punto , Agua , Microbiología de AlimentosRESUMEN
NAD(P)H: quinone oxidoreductase-1 (NQO1) plays critical roles in antioxidation and abnormally overexpresses in tumors. Developing a fast and sensitive method of monitoring NQO1 will greatly promote cancer diagnosis in clinical practice. This study introduces a transformative colorimetric detection strategy for NQO1, harnessing an innovative competitive substrate mechanism between NQO1 and a new NADH oxidase (NOX) mimic, cobalt-nitrogen-doped carbon nanozyme (CoNC). This method ingeniously exploits the differential consumption of NADH in the presence of NQO1 to modulate the generation of H2O2 from CoNC catalysis, which is then quantified through a secondary, peroxidase-mimetic cascade reaction involving Prussian blue (PB) nanoparticles. This dual-stage reaction framework not only enhances the sensitivity of NQO1 detection, achieving a limit of detection as low as 0.67 µg mL-1, but also enables the differentiation between cancerous and noncancerous cells by their enzymatic activity profiles. Moreover, CoNC exhibits exceptional catalytic efficiency, with a specific activity reaching 5.2 U mg-1, significantly outperforming existing NOX mimics. Beyond mere detection, CoNC serves a dual role, acting as both a robust mimic of cytochrome c reductase (Cyt c) and a cornerstone for enzymatic regeneration, thereby broadening the scope of its biological applications. This study not only marks a significant step forward in the bioanalytical application of nanozymes but also sets the stage for their expanded use in clinical diagnostics and therapeutic monitoring.
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Colorimetría , NAD(P)H Deshidrogenasa (Quinona) , NADH NADPH Oxidorreductasas , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , NAD(P)H Deshidrogenasa (Quinona)/química , Humanos , NADH NADPH Oxidorreductasas/metabolismo , Materiales Biomiméticos/química , Materiales Biomiméticos/metabolismo , Complejos Multienzimáticos/metabolismo , Complejos Multienzimáticos/química , Cobalto/química , Carbono/química , Biomimética , Límite de Detección , Nitrógeno/química , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/metabolismo , Ferrocianuros/química , NAD/metabolismo , NAD/químicaRESUMEN
Biosecurity encompasses the health and safety of humans, animals, plants, and the environment. In this article, "biosecurity" is defined as encompassing the comprehensive aspects of human, animal, plant, and environmental safety. Reliable biosecurity testing technology is the key point for effectively assessing biosecurity risks and ensuring biosecurity. Therefore, it is crucial to develop excellent detection technologies to detect risk factors that can affect biosecurity. An electrochemical microfluidic biosensing platform integrates fluid control, target recognition, signal transduction, and output and incorporates the advantages of electrochemical analysis technology and microfluidic technology. Thus, an electrochemical microfluidic biosensing platform, characterized by exceptional analytical sensitivity, portability, rapid analysis speed, low reagent consumption, and low risk of contamination, shows considerable promise for biosecurity detection compared to traditional, more complex, and time-consuming detection technologies. This review provides a concise introduction to electrochemical microfluidic biosensors and biosecurity. It highlights recent research advances in utilizing electrochemical microfluidic biosensing platforms to assess biosecurity risk factors. It includes the use of electrochemical microfluidic biosensors for the detection of risk factors directly endangering biosecurity (direct application: namely, risk factors directly endangering the health of human, animals, and plants) and for the detection of risk factors indirectly endangering biosecurity (indirect application: namely, risk factors endangering the safety of food and the environment). Finally, we outline the current challenges and future perspectives of electrochemical microfluidic biosensing platforms.
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Técnicas Biosensibles , Técnicas Electroquímicas , Técnicas Analíticas Microfluídicas , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Humanos , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Animales , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodosRESUMEN
BACKGROUND: Sapria himalayana (Rafflesiaceae) is an endoparasitic plant characterized by a greatly reduced vegetative body and giant flowers; however, the mechanisms underlying its special lifestyle and greatly altered plant form remain unknown. To illustrate the evolution and adaptation of S. himalayasna, we report its de novo assembled genome and key insights into the molecular basis of its floral development, flowering time, fatty acid biosynthesis, and defense responses. RESULTS: The genome of S. himalayana is ~ 1.92 Gb with 13,670 protein-coding genes, indicating remarkable gene loss (~ 54%), especially genes involved in photosynthesis, plant body, nutrients, and defense response. Genes specifying floral organ identity and controlling organ size were identified in S. himalayana and Rafflesia cantleyi, and showed analogous spatiotemporal expression patterns in both plant species. Although the plastid genome had been lost, plastids likely biosynthesize essential fatty acids and amino acids (aromatic amino acids and lysine). A set of credible and functional horizontal gene transfer (HGT) events (involving genes and mRNAs) were identified in the nuclear and mitochondrial genomes of S. himalayana, most of which were under purifying selection. Convergent HGTs in Cuscuta, Orobanchaceae, and S. himalayana were mainly expressed at the parasite-host interface. Together, these results suggest that HGTs act as a bridge between the parasite and host, assisting the parasite in acquiring nutrients from the host. CONCLUSIONS: Our results provide new insights into the flower development process and endoparasitic lifestyle of Rafflesiaceae plants. The amount of gene loss in S. himalayana is consistent with the degree of reduction in its body plan. HGT events are common among endoparasites and play an important role in their lifestyle adaptation.
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Genoma Mitocondrial , Transferencia de Gen Horizontal , Plantas/genética , Flores/genética , FilogeniaRESUMEN
By combining the distinctive noninvasive feature with the peculiar complete functional implementation trait, fully integrated raw noninvasive biofluid glucose biosensors offer active and remote glucose monitoring while posing minimal harm or infection risks compared to the traditional invasive manner. However, each previously reported fully integrated raw noninvasive biofluid glucose biosensor is solely focused on single-type raw noninvasive biofluid analysis. Given the diversity and complexity of subjects' physical conditions, single-type raw noninvasive biofluids are inappropriate to all crowds (e.g., sweat collection/analysis could be inapplicable for dermatopathic subjects). Here, we demonstrate the first example of a universal fully integrated nanoelectronic system with the unique capability to point-of-care and universally monitor diverse raw noninvasive biofluid (i.e., sweat, tears, and saliva) glucose by combining a flexible and disposable microfluidic enzymatic biosensor (named iezSlice) for raw biofluid pump-free sampling and measurement with a customized, handheld, and reusable wireless electronic device (named iezBar) for electrical signal transduction, conditioning, processing, and wireless transmission. We employed the specially designed high-concentration-buffer powder-loaded Kimwipes (HBP-KWs) as the microfluidic channel (microchannel) of iezSlice, guaranteeing a high-accuracy glucose analysis in various raw noninvasive biofluids. We also evaluated the potential utility of the universal fully integrated nanoelectronic system for noninvasive glucose management in healthy and diabetic subjects with the assistance of the proposed volatility-derived blood glucose concentration-free protocol. Although we focus on raw noninvasive biofluid glucose analysis in this work, the universal fully integrated nanoelectronic system may readily realize accurate monitoring of various biomolecules in raw noninvasive biofluids by introducing corresponding bioreceptors.
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Técnicas Biosensibles , Glucemia , Técnicas Biosensibles/métodos , Automonitorización de la Glucosa Sanguínea , Glucosa , Humanos , Microfluídica , Sistemas de Atención de Punto , Saliva , SudorRESUMEN
The present detection method for hepatitis B virus (HBV) drug-resistant mutation has a high misdiagnosis rate and usually needs to meet stringent requirements for technology and equipment, leading to complex and time-consuming manipulation and drawback of high costs. Herein, with the purpose of developing cost-effective, highly efficient, and handy diagnosis for HBV drug-resistant mutants, we propose an electrochemical signal-on strategy through the three-way junction (3WJ) transduction and exonuclease III (Exo III)-assisted catalyzed hairpin assembly (CHA). To achieve single-copy gene detection, loop-mediated nucleic acid isothermal amplification (LAMP), one of the highly promising and compatible techniques to revolutionize point-of-care genetic detection, is first adopted for amplification. The rtN236T mutation, an error encoded by codon 236 of the reverse transcriptase region of HBV DNA, was employed as the model gene target. Under the optimized conditions, it allows end-point transduction from HBV drug-resistant mutants-genomic information to electrochemical signals with ultrahigh sensitivity, specificity, and signal-to-noise ratio, showing the lowest detection concentration down to 2 copies/µL. Such a method provides a possibly new principle for ideal in vitro diagnosis, supporting the construction of a clinic HBV diagnosis platform with high accuracy and generalization. Moreover, it is not restricted by specific nucleic acid sequences but can be applied to the detection of various disease genes, laying the foundation for multiple detection.
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Técnicas Biosensibles , Virus de la Hepatitis B , Técnicas Biosensibles/métodos , Catálisis , ADN/genética , Exodesoxirribonucleasas , Virus de la Hepatitis B/genética , Técnicas de Amplificación de Ácido Nucleico/métodosRESUMEN
BACKGROUND: Plastomes of heterotrophic plants have been greatly altered in structure and gene content, owing to the relaxation of selection on photosynthesis-related genes. The orchid tribe Gastrodieae is the largest and probably the oldest mycoheterotrophic clade of the extant family Orchidaceae. To characterize plastome evolution across members of this key important mycoheterotrophic lineage, we sequenced and analyzed the plastomes of eleven Gastrodieae members, including representative species of two genera, as well as members of the sister group Nervilieae. RESULTS: The plastomes of Gastrodieae members contain 20 protein-coding, four rRNA and five tRNA genes. Evolutionary analysis indicated that all rrn genes were transferred laterally and together, forming an rrn block in the plastomes of Gastrodieae. The plastome GC content of Gastrodia species ranged from 23.10% (G. flexistyla) to 25.79% (G. javanica). The plastome of Didymoplexis pallens contains two copies each of ycf1 and ycf2. The synonymous and nonsynonymous substitution rates were very high in the plastomes of Gastrodieae among mycoheterotrophic species in Orchidaceae and varied between genes. CONCLUSIONS: The plastomes of Gastrodieae are greatly reduced and characterized by low GC content, rrn block formation, lineage-specific reconfiguration and gene content, which might be positively selected. Overall, the plastomes of Gastrodieae not only serve as an excellent model for illustrating the evolution of plastomes but also provide new insights into plastome evolution in parasitic plants.
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Genoma de Plastidios , Orchidaceae , Procesos Heterotróficos/genética , Orchidaceae/genética , Fotosíntesis/genéticaRESUMEN
We present a facile route towards a dual single-atom nanozyme composed of Zn and Mo, which utilizes the non-covalent nano-assembly of polyoxometalates, supramolecular coordination complexes as the metal-atom precursor, and a macroscopic amphiphilic aerogel as the supporting substrate. The dual single-atoms of Zn and Mo have a high content (1.5 and 7.3â wt%, respectively) and exhibit a synergistic effect and a peroxidase-like activity. The Zn/Mo site was identified as the main active center by X-ray absorption fine structure spectroscopy and density functional theory calculation. The detection of versatile analytes, including intracellular H2 O2 , glucose in serum, cholesterol, and ascorbic acid in commercial beverages was achieved. The nanozyme has an outstanding stability and maintained its performance after one year's storage. This study develops a new peroxidase-like nanozyme and provides a robust synthetic strategy for single-atom catalysts by utilizing an aerogel as a facile substrate that is capable of stabilizing various metal atoms.
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Antioxidantes , Peroxidasa , Catálisis , Peroxidasa/química , Peroxidasas , ZincRESUMEN
In this paper, sweet potatoes (Ipomoea batatas) are used as low-cost precursors to synthesize carbon aerogels with a hierarchical meso-macroporous and branching nanostructure (HMM-BNCA). An HMM-BNCA-modified glassy carbon electrode (GCE) (HMM-BNCA/GCE) exhibits high electrocatalytic activity for some electroactive biomolecules. For ascorbic acid (AA), the HMM-BNCA/GCE exhibits low oxidation peak potential and detection limit (-0.005 V and 0.45 µM, S/N = 3), high sensitivities (195.43 and 121.00 µA mM-1 cm-2) and wide linear ranges (10-1250 µM and 1250-4750 µM), which are superior to those obtained at the GCE and carbon nanotube (CNT)-modified GCE (CNT/GCE). The HMM-BNCA/GCE exhibits significant resistance to fouling and the interfering substances for the detection of AA. The successful and accurate detection of AA in real samples (such as vitamin C injections and vitamin C soft drinks) in this work demonstrates the feasibility and tremendous potential of HMM-BNCA/GCE for the analysis of AA in complex systems.
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Natural enzyme complex with the subunits cooperating with each other could catalyze cascade reactions in biological system but, just like the limitation of free-floating natural enzymes, usually suffer from deactivation in harsh environment such as high temperature. In this study, a purpose-driven design of amphiphilic aerogel working as the enzymes-immobilization substrate to form the multienzyme complex (MEC) was demonstrated. The aerogel was synthesized only by a single polymer poly(vinyl alcohol) (PVA) as well as a surface modulator maleic acid (MA), the incorporation of which tunes the surface wettability. The usage of the amphiphilic aerogel may do favor for multienzyme immobilization, conserving the enzyme conformation as well as stabilizing the enzymes in high temperature. As a typical example, glucose oxidase and hemin were firmly coimmobilized in the aerogel matrix and actively catalyze the cascade reactions of (i) glucose to gluconic acid and (ii) 3,3,5,5-tetramethylbenzidine (TMB) to its oxidized state. The enzymes could resist the degradation under high temperature (70-100 °C) which is witnessed by the rate of decrease in activity was progressively slackened. Taking the advantage of the chromogenic reaction of TMB, a glucose sensor based on aerogel-enzyme composite for glucose detection in whole blood and sweat was established, exhibiting reliable results and satisfactory recovery. The modified aerogel could also withstand multiple physical deformation meantime maintaining good adsorption capacity as well as catalytic performance. The enzymes-loading aerogel model may hopefully contribute to composing sensors based on other analytes.
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Enzimas Inmovilizadas/química , Glucosa/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Límite de Detección , Biocatálisis , Glucemia/análisis , Estabilidad de Enzimas , Enzimas Inmovilizadas/metabolismo , Geles , Glucosa Oxidasa/química , Glucosa Oxidasa/metabolismo , Hemina/química , Hemina/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Maleatos/química , Modelos Moleculares , Conformación Molecular , Alcohol Polivinílico/química , Sudor/química , TemperaturaRESUMEN
Photothermal conversion ability (PCA) and cell internalization ability (CIA) are two key factors for determining the performance of photothermal agents. The previous studies mostly focus on improving the PCA by exploring new photothermal nanomaterials. Herein, the authors take the hybrids of graphene and gold nanostar (GGN) as an example to investigate the gradually enhanced phototherapy effect by changing the PCA and CIA of photothermal therapy (PTT) agent simultaneously. Based on the GGN, the GGN and the reduced GGN protected by bovine serum albumin (BSA) or BSA-FA (folic acid) are prepared, which are named as GGNB, rGGNB, and rGGNB-FA, respectively. The rGGNB showed an enhanced PCA compared to GGNB, leading to strong cell ablation. On the other hand, the 1,2-dioleoyl-3-trimethylammoniumpropan (DOTAP) can activate the endocytosis and promote the CIA of rGGNB, further help rGGNB to be more internalized into the cells. Finally, rGGNB-FA with the target ability can make itself further internalized into the cells with the aid of DOTAP, which can significantly destroy the cancer cells even at the low laser density of 0.3 W cm-2 . Therefore, a new angle of view is brought out for researching the PTT agents of high performance.
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Grafito/química , Nanoestructuras/química , Fototerapia/métodos , Ácidos Grasos Monoinsaturados/química , Compuestos de Amonio Cuaternario/químicaRESUMEN
Self-healing materials emerge as a fascinating class of materials important for various technological applications. However, achieving the synergistic characteristics of high conductivity, room-temperature self-healing ability, and decent mechanical properties still remains a critical challenge. Here we develop for the first time a hybrid gel based on self-assembled supramolecular gel and nanostructured polypyrrole that synergizes the dynamic assembly/disassembly nature of metal-ligand supramolecule and the conductive nanostructure of polypyrrole hydrogel and exhibits features of high conductivity (12 S m(-1)), appealing mechanical and electrical self-healing property without any external stimuli, and enhanced mechanical strength and flexibility. The attractive characteristics of the hybrid gel are further demonstrated by a flexible yet self-healable electrical circuit. Our work shows the great potential of self-healing hybrid gel system in flexible electronics and provides a useful strategy to design multifunctional self-healing materials.
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Thermally responsive hydrogels have drawn significant research attention recently because of their simple use as drug carrier at human body temperature. Here we design a hybrid hydrogel that incorporates a hydrophilic polymer, polyethyleneimine (PEI), into the thermally responsive hydrogel poly(N-isopropylacrylamide) (PNIPAm), as a general drug carrier model for controlled drug release. In this work, on one hand, PEI modifies the structure and the size of the pores in the PNIPAm hydrogel. On the other hand, PEI plays an important role in tuning the water content in the hydrogel and controls the water release rate of the hydrogel below the lower critical solution temperature (LCST), resulting in a tunable release rate of the drugs at human body temperature (37 °C). Different release rates are shown as different amounts of PEI are incorporated. PEI controls the release rate, dependent on the charge characteristics of the drugs. The hydrogel blends described in this work extend the concept of a general drug carrier for loading both positively and negatively charged drugs, as well as the controlled release effect.
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Resinas Acrílicas/química , Preparaciones de Acción Retardada/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Polietileneimina/química , Liberación de Fármacos , TemperaturaRESUMEN
Effective wound healing is critical for patient care, and the development of novel wound dressing materials that promote healing, prevent infection, and are user-friendly is of great importance, particularly in the context of point-of-care testing (POCT). This study reports the synthesis of a hydrogel material that can be produced in less than 10 s and possesses antibacterial activity against both gram-negative and gram-positive microorganisms, as well as the ability to inhibit the growth of eukaryotic cells, such as yeast. The hydrogel is formed wholly based on covalent-like hydrogen bonding interactions and exhibits excellent mechanical properties, with the ability to stretch up to more than 600% of its initial length. Furthermore, the hydrogel demonstrates ultra-fast self-healing properties, with fractures capable of being repaired within 10 s. This hydrogel can promote skin wound healing, with the added advantage of functioning as a strain sensor that generates an electrical signal in response to physical deformation. The strain sensor composed of a rubber shell realizes fast and responsive strain sensing. The findings suggest that this hydrogel has promising applications in the field of POCT for wound care, providing a new avenue for improved patient outcomes.
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Hidrogeles , Traumatismos de los Tejidos Blandos , Humanos , Piel , Epidermis , AntibacterianosRESUMEN
A new species of Orchidaceae, Phalaenopsiszhanhouana, from Xichou County, Yunnan, China, is described and illustrated. The novelty is close to P.taenialis, P.wilsonii, and P.stobartiana, but differs from them by having a distinct, fleshy anterior callus with a deeply lobed apex at the base of the labellum and lateral lobes of labellum reflexed and facing outward.
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The integration of smartphones with conventional analytical approaches plays a crucial role in enhancing on-site detection platforms for point-of-care testing. Here, we developed a simple, rapid, and efficient three-channel colorimetric sensor array, leveraging the peroxidase (POD)-like activity of polydopamine-decorated FeNi foam (PDFeNi foam), to identify antioxidants using both microplate readers and smartphones for signal readouts. The exceptional catalytic capacity of PDFeNi foam enabled the quick catalytic oxidation of three typical peroxidase substrates (TMB, OPD and 4-AT) within 3 min. Consequently, we constructed a colorimetric sensor array with cross-reactive responses, which was successfully applied to differentiate five antioxidants (i.e., glycine (GLY), glutathione (GSH), citric acid (CA), ascorbic acid (AA), and tannic acid (TAN)) within the concentration range of 0.1-10 µM, quantitatively analyze individual antioxidants (with AA and CA as model analytes), and assess binary mixtures of AA and GSH. The practical application was further validated by discriminating antioxidants in serum samples with a smartphone for signal readout. In addition, since pesticides could be absorbed on the surface of PDFeNi foam through π-π stacking and hydrogen bonding, the active sites were differentially masked, leading to featured modulation on POD-like activity of PDFeNi foam, thereby forming the basis for pesticides discrimination on the sensor array. The nanozyme-based sensor array provides a simple, rapid, visual and high-throughput strategy for precise identification of various analytes with a versatile platform, highlighting its potential application in point-care-of diagnostic, food safety and environmental surveillance.
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Antioxidantes , Colorimetría , Indoles , Plaguicidas , Teléfono Inteligente , Colorimetría/métodos , Antioxidantes/análisis , Antioxidantes/química , Plaguicidas/análisis , Plaguicidas/sangre , Indoles/química , Polímeros/química , HumanosRESUMEN
BACKGROUND: There is widespread interest in the design of portable electrochemical sensors for the selective monitoring of biomolecules. Dopamine (DA) is one of the neurotransmitter molecules that play a key role in the monitoring of some neuronal disorders such as Alzheimer's and Parkinson's diseases. Facile synthesis of the highly active surface interface to design a portable electrochemical sensor for the sensitive and selective monitoring of biomolecules (i.e., DA) in its resources such as human fluids is highly required. RESULTS: The designed sensor is based on a three-dimensional phosphorous and sulfur resembling a g-C3N4 hornet's nest (3D-PS-doped CNHN). The morphological structure of 3D-PS-doped CNHN features multi-open gates and numerous vacant voids, presenting a novel design reminiscent of a hornet's nest. The outer surface exhibits a heterogeneous structure with a wave orientation and rough surface texture. Each gate structure takes on a hexagonal shape with a wall size of approximately 100 nm. These structural characteristics, including high surface area and hierarchical design, facilitate the diffusion of electrolytes and enhance the binding and high loading of DA molecules on both inner and outer surfaces. The multifunctional nature of g-C3N4, incorporating phosphorous and sulfur atoms, contributes to a versatile surface that improves DA binding. Additionally, the phosphate and sulfate groups' functionalities enhance sensing properties, thereby outlining selectivity. The resulting portable 3D-PS-doped CNHN sensor demonstrates high sensitivity with a low limit of detection (7.8 nM) and a broad linear range spanning from 10 to 500 nM. SIGNIFICANCE: The portable DA sensor based on the 3D-PS-doped CNHN/SPCE exhibits excellent recovery of DA molecules in human fluids, such as human serum and urine samples, demonstrating high stability and good reproducibility. The designed portable DA sensor could find utility in the detection of DA in clinical samples, showcasing its potential for practical applications in medical settings.
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Dopamina , Técnicas Electroquímicas , Dopamina/análisis , Dopamina/orina , Humanos , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Compuestos de Nitrógeno/química , Límite de Detección , Azufre/química , Electrodos , Técnicas Biosensibles/métodos , Grafito/química , Fósforo/química , Propiedades de SuperficieRESUMEN
Efficient detection of pathogenic bacteria is paramount for ensuring food safety and safeguarding public health. Herein, we developed a label-free and signal-on dual-target recognition electrochemical DNA sensing platform based on the conformational formation of split G-quadruplex. This platform focused on achieving sensitive and low-cost detection of Salmonella and its most human-infecting S. typhimurium serotype. In simple terms, the dual-target recognition probe (DTR-6P) was ingeniously designed for the loop sequence on the loop-mediated isothermal amplification (LAMP) amplicons. It could recognize two different genes and release their corresponding G-rich sequences. The exfoliated G-rich sequences could be captured by the capture probes on the electrode, and then the bimolecular G-quadruplex or the tetramolecular G-quadruplex would be formed to capture hemin, thereby enabling dual-signal reporting. The minimum detection amount of target genes can be as low as 2 copies/µL. Encouragingly, the real food samples contaminated by Salmonella and the S. typhimurium serotype can be readily identified. The sensing platform with ingenious design paves a new way for label-free, multi-target simultaneous detection, whose advantage of rapidity, sensitivity, cost-effectiveness, and specificity also lay a solid foundation for practical applications.
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Técnicas Biosensibles , ADN Catalítico , G-Cuádruplex , Humanos , Hemina/química , Serogrupo , ADN/química , Salmonella/genética , ADN Catalítico/química , Técnicas Electroquímicas , Límite de DetecciónRESUMEN
With the rapid evolution of sensing technologies, the integration of nanoscale catalysts, particularly those mimicking enzymatic functions, into electrochemical devices has surfaced as a pivotal advancement. These catalysts, dubbed artificial enzymes, embody a blend of heightened sensitivity, selectivity, and durability, laying the groundwork for innovative applications in real-time health monitoring and environmental detection. This minireview penetrates into the fundamental principles of electrochemical sensing, elucidating the unique attributes that establish artificial enzymes as foundational elements in this field. We spotlight a range of innovations where these catalysts have been proficiently incorporated into wearable and portable platforms. Navigating the pathway of amalgamating these nanoscale wonders into consumer-appealing devices presents a multitude of challenges; nevertheless, the progress made thus far signals a promising trajectory. As the intersection of materials science, biochemistry, and electronics progressively intensifies, a flourishing future seems imminent for artificial enzyme-infused electrochemical devices, with the potential to redefine the landscapes of wearable health diagnostics and portable sensing solutions.
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Técnicas Biosensibles , Dispositivos Electrónicos Vestibles , ElectrónicaRESUMEN
A new species of Orchidaceae, Phalaenopsismedogensis, from Motuo, Xizang, is described and illustrated based on morphological characters and molecular phylogenetics analysis. Molecular phylogenetic analysis and morphological characters indicate that P.medogensis is close to P.deliciosa, P.gibbosa and P.lobbii, but differs from them by having triangular wings on the column foot, rhombic lip mid-lobe with a fleshy-horned appendage at the base, and concave lip lateral lobes, the lower part white with a deep purplish-red spot and hairy, the upper part pale yellow with dense rust spots.