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1.
Anal Methods ; 16(19): 3007-3019, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38695537

RESUMEN

We present a colorimetric probe based on polyvinylpyrrolidone-capped gold nanoparticles (PVP-AuNPs) that is sensitive and selective for cysteine (Cys). A microfluidic paper-based analytical device (µ-PAD) with embedded dried PVP-AuNPs at the polyethersulfone (PES) paper surface is used for Cys detection. When thiol molecules attach to PVP-AuNPs in the presence of Cys, they clump together, and this causes the solution's color to shift from red to blue within 5 minutes. The device is capable of detecting Cys levels between 1.0 µM and 50.0 µM with a limit of detection (LOD) of 0.2 µM under optimized conditions. The stability of the µ-PAD was tested for 100 days, demonstrating re-dispersibility to detect Cys levels in blood. Dried PVP-AuNP-µPADs were integrated with blood plasma separation modules for point-of-care (POC) Cys detection. Consequently, the device shows potential as a self-sustaining, quantification platform with a recovery percentage ranging from 98.44 to 111.9 in clinical samples.


Asunto(s)
Colorimetría , Cisteína , Oro , Límite de Detección , Nanopartículas del Metal , Papel , Sistemas de Atención de Punto , Oro/química , Cisteína/sangre , Cisteína/química , Nanopartículas del Metal/química , Humanos , Colorimetría/métodos , Colorimetría/instrumentación , Povidona/química , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos
2.
Anal Methods ; 16(19): 3131-3141, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38712986

RESUMEN

Plastics are ubiquitous in today's lifestyle, and their indiscriminate use has led to the accumulation of plastic waste in landfills and oceans. The waste accumulates and breaks into micro-particles that enter the food chain, causing severe threats to human health, wildlife, and the ecosystem. Environment-friendly and bio-based degradable materials offer a sustainable alternative to the vastly used synthetic materials. Here, a polylactic acid and carbon nanofiber-based membrane and a paper-based colorimetric sensor have been developed. The membrane had a surface area of 3.02 m2 g-1 and a pore size of 18.77 nm. The pores were evenly distributed with a pore volume of 0.0137 cm3 g-1. The membrane was evaluated in accordance with OECD guidelines and was found to be safe for tested aquatic and terrestrial models. The activated PLA-CNF membrane was further used as a bio-based electrode for the electrochemical detection of nitrates (NO3-) in water samples with a detection limit of 0.046 ppm and sensitivity of 1.69 × 10-4 A ppm-1 mm-2, whereas the developed paper-based colorimetric sensor had a detection limit of 156 ppm for NO3-. This study presents an environment-friendly, low-carbon footprint disposable material for sensing applications as a sustainable alternative to plastics.


Asunto(s)
Carbono , Colorimetría , Nanofibras , Nitratos , Papel , Poliésteres , Nanofibras/química , Colorimetría/métodos , Colorimetría/instrumentación , Nitratos/análisis , Nitratos/química , Poliésteres/química , Carbono/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Límite de Detección , Contaminantes Químicos del Agua/análisis , Conductividad Eléctrica , Membranas Artificiales
3.
J Nanobiotechnology ; 22(1): 274, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38773614

RESUMEN

Small extracellular vesicle-derived microRNAs (sEV-miRNAs) have emerged as promising noninvasive biomarkers for early cancer diagnosis. Herein, we developed a molecular probe based on three-dimensional (3D) multiarmed DNA tetrahedral jumpers (mDNA-Js)-assisted DNAzyme activated by Na+, combined with a disposable paper-based electrode modified with a Zr-MOF-rGO-Au NP nanocomplex (ZrGA) to fabricate a novel biosensor for sEV-miRNAs Assay. Zr-MOF tightly wrapped by rGO was prepared via a one-step method, and it effectively aids electron transfer and maximizes the effective reaction area. In addition, the mechanically rigid, and nanoscale-addressable mDNA-Js assembled from the bottom up ensure the distance and orientation between fixed biological probes as well as avoid probe entanglement, considerably improving the efficiency of molecular hybridization. The fabricated bioplatform achieved the sensitive detection of sEV-miR-21 with a detection limit of 34.6 aM and a dynamic range from100 aM to 0.2 µM. In clinical blood sample tests, the proposed bioplatform showed results highly consistent with those of qRT-PCRs and the signal increased proportionally with the NSCLC staging. The proposed biosensor with a portable wireless USB-type analyzer is promising for the fast, easy, low-cost, and highly sensitive detection of various nucleic acids and their mutation derivatives, making it ideal for POC biosensing.


Asunto(s)
Técnicas Biosensibles , Vesículas Extracelulares , Límite de Detección , Estructuras Metalorgánicas , MicroARNs , Papel , Estructuras Metalorgánicas/química , Vesículas Extracelulares/química , Humanos , Técnicas Biosensibles/métodos , ADN Catalítico/química , Grafito/química , Oro/química , ADN/química , Nanopartículas del Metal/química , Hibridación de Ácido Nucleico , Técnicas Electroquímicas/métodos , Electrodos , Circonio/química
4.
Anal Chim Acta ; 1306: 342617, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38692789

RESUMEN

BACKGROUND: Alpha-fetoprotein (AFP) is a fetal protein that can indicate congenital anomalies such as Down syndrome and spinal canal blockage when detected at abnormal levels in pregnant women. Current AFP detection methods rely on invasive blood or serum samples, which require sophisticated equipment. From the many solutions proposed, colorimetric paper-based assays excel in point-of-care settings. The concept of paper-based ELISA (p-ELISA) enhances traditional methods, aligning with the ASSURED criteria for diagnostics in resource-limited regions. Despite success in microfluidic paper-based assay devices, laser printing remains underexplored for p-ELISA. Additionally, modifying the paper surface provides an additional layer of sensitivity enhancement. RESULTS: In this study, we developed a novel laser-printed paper-based ELISA (LP-pELISA) for rapid, sensitive, and noninvasive detection of AFP in saliva samples. The LP-pELISA platform was fabricated by printing hydrophobic barriers on filter paper using a laser printer, followed by depositing hydroxyapatite (HAp) as an immobilization material for the antibodies. The colorimetric detection was achieved using AuNPs functionalized with anti-AFP antibodies and silver nitrate enhancement. The LP-pELISA exhibited a linear response for AFP detection in both buffer and saliva samples over a range of 1.0-800 ng mL-1, with a limit of detection (LOD) reaching 1.0 ng mL-1. The assay also demonstrated good selectivity, repeatability, reproducibility, and stability. The LP-pELISA was further validated by testing spiked human saliva samples, showing its potential for point-of-care diagnosis of congenital disabilities. SIGNIFICANCE: The LP-pELISA is a noninvasive platform showcasing simplicity, cost-effectiveness, and user-friendliness, utilizing laser printing, hydroxyapatite modification, and saliva samples to efficiently detect AFP. Beyond its application for AFP, this method's versatility extends to other biomarkers, positioning it as a catalyst for the evolution of paper-based biosensors. The LP-pELISA holds promise as a transformative tool for point-of-care diagnostics, fostering advancements in healthcare with its innovative technology.


Asunto(s)
Colorimetría , Durapatita , Ensayo de Inmunoadsorción Enzimática , Rayos Láser , Papel , Saliva , alfa-Fetoproteínas , Humanos , Saliva/química , Durapatita/química , alfa-Fetoproteínas/análisis , Impresión , Oro/química , Límite de Detección , Anticuerpos Inmovilizados/inmunología , Anticuerpos Inmovilizados/química
5.
Cancer Med ; 13(9): e7189, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38706442

RESUMEN

OBJECTIVES: Endoscopic ultrasound-guided tissue acquisition (EUS-TA) is used for pathological diagnosis and obtaining samples for molecular testing, facilitating the initiation of targeted therapies in patients with pancreatic cancer. However, samples obtained via EUS-TA are often insufficient, requiring more efforts to improve sampling adequacy for molecular testing. Therefore, this study investigated the use of oil blotting paper for formalin fixation of samples obtained via EUS-TA. METHODS: This prospective study enrolled 42 patients who underwent EUS-TA for pancreatic cancer between September 2020 and February 2022 at the Osaka International Cancer Institute. After a portion of each sample obtained via EUS-TA was separated for routine histological evaluation, the residual samples were divided into filter paper and oil blotting paper groups for analysis. Accordingly, filter paper and oil blotting paper were used for the formalin fixation process. The total tissue, nuclear, and cytoplasm areas of each sample were quantitatively evaluated using virtual slides, and the specimen volume and histological diagnosis of each sample were evaluated by an expert pathologist. RESULTS: All cases were cytologically diagnosed as adenocarcinoma. The area ratios of the total tissue, nuclear, and cytoplasmic portions were significantly larger in the oil blotting paper group than in the filter paper group. The frequency of cases with large amount of tumor cells was significantly higher in the oil blotting paper group (33.3%) than in the filter paper group (11.9%) (p = 0.035). CONCLUSIONS: Oil blotting paper can increase the sample volume obtained via EUS-TA on glass slides and improve sampling adequacy for molecular testing.


Asunto(s)
Formaldehído , Neoplasias Pancreáticas , Fijación del Tejido , Humanos , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/diagnóstico por imagen , Estudios Prospectivos , Masculino , Femenino , Fijación del Tejido/métodos , Anciano , Persona de Mediana Edad , Endosonografía/métodos , Manejo de Especímenes/métodos , Adenocarcinoma/patología , Adenocarcinoma/diagnóstico por imagen , Anciano de 80 o más Años , Papel , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos
6.
Anal Chim Acta ; 1308: 342575, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38740448

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is a prevalent neurodegenerative disease with no effective treatment. Efficient and rapid detection plays a crucial role in mitigating and managing AD progression. Deep learning-assisted smartphone-based microfluidic paper analysis devices (µPADs) offer the advantages of low cost, good sensitivity, and rapid detection, providing a strategic pathway to address large-scale disease screening in resource-limited areas. However, existing smartphone-based detection platforms usually rely on large devices or cloud servers for data transfer and processing. Additionally, the implementation of automated colorimetric enzyme-linked immunoassay (c-ELISA) on µPADs can further facilitate the realization of smartphone µPADs platforms for efficient disease detection. RESULTS: This paper introduces a new deep learning-assisted offline smartphone platform for early AD screening, offering rapid disease detection in low-resource areas. The proposed platform features a simple mechanical rotating structure controlled by a smartphone, enabling fully automated c-ELISA on µPADs. Our platform successfully applied sandwich c-ELISA for detecting the ß-amyloid peptide 1-42 (Aß 1-42, a crucial AD biomarker) and demonstrated its efficacy in 38 artificial plasma samples (healthy: 19, unhealthy: 19, N = 6). Moreover, we employed the YOLOv5 deep learning model and achieved an impressive 97 % accuracy on a dataset of 1824 images, which is 10.16 % higher than the traditional method of curve-fitting results. The trained YOLOv5 model was seamlessly integrated into the smartphone using the NCNN (Tencent's Neural Network Inference Framework), enabling deep learning-assisted offline detection. A user-friendly smartphone application was developed to control the entire process, realizing a streamlined "samples in, answers out" approach. SIGNIFICANCE: This deep learning-assisted, low-cost, user-friendly, highly stable, and rapid-response automated offline smartphone-based detection platform represents a good advancement in point-of-care testing (POCT). Moreover, our platform provides a feasible approach for efficient AD detection by examining the level of Aß 1-42, particularly in areas with low resources and limited communication infrastructure.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Biomarcadores , Ensayo de Inmunoadsorción Enzimática , Papel , Teléfono Inteligente , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/sangre , Humanos , Biomarcadores/sangre , Biomarcadores/análisis , Péptidos beta-Amiloides/análisis , Péptidos beta-Amiloides/sangre , Fragmentos de Péptidos/sangre , Fragmentos de Péptidos/análisis , Dispositivos Laboratorio en un Chip , Aprendizaje Profundo , Automatización , Técnicas Analíticas Microfluídicas/instrumentación
7.
Anal Chim Acta ; 1308: 342639, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38740452

RESUMEN

BACKGROUND: Calcium and magnesium ions are highly abundant and important cations in human body. At the same time, both dyscalcemia and dysmagnesemia are frequently encountered in the clinical practice. As deficiency or excess of Ca(II) or Mg(II) can cause severe symptoms, determining these ions in serum is of great importance. Concentration of these ions in biological samples is typically assayed in clinical laboratories with the use of expensive and specialized equipment. Since those methods cannot be easily adapted for self-diagnosis purposes, there is a great need to develop a convenient tool for reliable determination of calcium and magnesium in serum at the point-of-care. RESULTS: The colorimetric methods employed for calcium and magnesium analysis were o-cresophtalein complexone assay and xylidyl blue assay, respectively. Analytical signal acquisition was accomplished using an ordinary flatbed scanner or smartphone and free software. For increased user-friendliness the device was optimized to perform simultaneous determination of calcium and magnesium ions in only 10 min. In the optimized conditions, the limit of detection for calcium ions was 0.09 mmol L-1, while for magnesium it was 0.04 mmol L-1. Determination of both ions requires only 4 µL of serum sample. The developed paper-based sensors were validated with control human serum samples and the obtained relative errors for majority of samples were below 20 %. SIGNIFICANCE: In this paper, a microfluidic paper-based analytical device for simultaneous determination of calcium and magnesium ions in human serum is reported for the first time. Additionally, this is also the first report on colorimetric determination in serum of any of these ions in paper-based format. Simultaneous detection of both ions allows for fast and user-friendly screening of disturbance in calcium and magnesium homeostasis.


Asunto(s)
Calcio , Magnesio , Papel , Magnesio/sangre , Humanos , Calcio/sangre , Colorimetría , Dispositivos Laboratorio en un Chip , Técnicas Analíticas Microfluídicas/instrumentación , Límite de Detección
8.
J Mass Spectrom ; 59(6): e5036, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38726689

RESUMEN

Turmeric and ginger are extensively employed as functional ingredients due to their high content of curcuminoids and gingerols, considered the key bioactive compounds found in these roots. In this study, we present an innovative and fast method for the assay of curcuminoids and gingerols in different foods containing the two spices, with the aim of monitoring the quality of products from a nutraceutical perspective. The proposed approach is based on paper spray tandem mass spectrometry coupled with the use of a labeled internal standard, which has permitted to achieve the best results in terms of specificity and accuracy. All the calculated analytical parameters were satisfactory; accuracy values are around 100% for all spiked samples and the precision data result lower than 15%. The protocol was applied to several real samples, and to demonstrate its robustness and reliability, the results were compared to those arising from the common liquid chromatographic method.


Asunto(s)
Curcuma , Alcoholes Grasos , Espectrometría de Masas en Tándem , Zingiber officinale , Zingiber officinale/química , Curcuma/química , Espectrometría de Masas en Tándem/métodos , Alcoholes Grasos/análisis , Reproducibilidad de los Resultados , Límite de Detección , Catecoles/análisis , Análisis de los Alimentos/métodos , Curcumina/análisis , Curcumina/análogos & derivados , Papel
9.
Environ Sci Pollut Res Int ; 31(20): 30126-30136, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38602641

RESUMEN

Globally, per- and polyfluoroalkyl substances (PFAS)-related research on paper products has focused on food packaging with less consideration on the presence of PFAS at different stages of the paper recycling chain. This study analysed the prevalence of PFAS in paper grades used for the manufacture of recycled paperboard. The presence of PFAS was attributed to the use of PFAS-containing additives, consumer usage, exposure to packed goods as well as contamination during mingling, sorting, collection, and recovery of paper recycling material. Q Orbitrap mass spectrometry was used to analyse the paper samples after accelerated solvent extraction and solid phase extraction. The distribution and possible propagation of 22 PFAS were determined in pre-consumer, retail and post-consumer paper products. Post-consumer samples had the highest combined average concentration (ΣPFAS) at 213 ng/g, while the ΣPFAS in retail (159 ng/g) and pre-consumer samples (121 ng/g) was detected at lower concentrations. This study showed that waste collection and recycling protocols may influence PFAS propagation and that measures must be developed to minimise and possibly eliminate exposure opportunities.


Asunto(s)
Fluorocarburos , Espectrometría de Masas , Papel , Reciclaje , Fluorocarburos/análisis , Cromatografía Líquida de Alta Presión , Extracción en Fase Sólida
10.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124290, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38669984

RESUMEN

Hydrogen Peroxide (H2O2) is a highly hazardous, toxic, and carcinogenic chemical compound utilised in various industries-based applications. Despite strict restriction, they are deliberately added to food items such as milk as preservatives to increase its shelf life. Herein, we have formulated a green rapid colorimetric nanosensor for detection of H2O2 in milk using cotton leaves as both reducing and functionalizing agent for synthesis of silver nanoparticles (AgNPs). UV-Vis spectra exhibit a strong plasmonic peak at around 434 nm. X-Ray Diffraction (XRD) analysis was performed to determine the crystallinity of the nanoparticles. Field Emission Scanning Electron Microscope (FESEM) and Transmission Electron Microscope (TEM) characterizations revealed spherical morphology with size approximately âˆ¼16 nm. This functionalized nanoparticle could colorimetrically sense presence of H2O2 in milk samples both in liquid media and on paper substrates with Limit of Detection (LOD) of 8.46 ppm even in presence of other interfering substances in milk. This inexpensive route will pave the way for in depth research.


Asunto(s)
Colorimetría , Peróxido de Hidrógeno , Límite de Detección , Nanopartículas del Metal , Leche , Papel , Plata , Peróxido de Hidrógeno/análisis , Peróxido de Hidrógeno/química , Leche/química , Colorimetría/métodos , Animales , Plata/química , Nanopartículas del Metal/química , Nanoestructuras/química , Espectrofotometría Ultravioleta
11.
Anal Methods ; 16(18): 2777-2809, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38639474

RESUMEN

Paper-based sensors, often referred to as paper-based analytical devices (PADs), stand as a transformative technology in the field of analytical chemistry. They offer an affordable, versatile, and accessible solution for diverse analyte detection. These sensors harness the unique properties of paper substrates to provide a cost-effective and adaptable platform for rapid analyte detection, spanning chemical species, biomolecules, and pathogens. This review highlights the key attributes that make paper-based sensors an attractive choice for analyte detection. PADs demonstrate their versatility by accommodating a wide range of analytes, from ions and gases to proteins, nucleic acids, and more, with customizable designs for specific applications. Their user-friendly operation and minimal infrastructure requirements suit point-of-care diagnostics, environmental monitoring, food safety, and more. This review also explores various fabrication methods such as inkjet printing, wax printing, screen printing, dip coating, and photolithography. Incorporating nanomaterials and biorecognition elements promises even more sophisticated and sensitive applications.


Asunto(s)
Técnicas Biosensibles , Papel , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Humanos , Diseño de Equipo , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/instrumentación , Ácidos Nucleicos/análisis , Proteínas/análisis , Nanoestructuras/química
12.
Technol Cult ; 65(1): 63-87, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38661794

RESUMEN

This article questions the economic rationale of colonial experimentation and prison labor, arguing that for many administrators a prison-based experiment's success mattered less than its existence. It examines the position of convict labor and penal discipline within colonial industrial experiments in colonial India, where convicts performed experiments for what one administrator described as "the most penal" form of labor, papermaking. The belief that Indian fibers could open a new export market for global papermaking meant that prisons became prominent sites of experimentation with new pulps. Regional prisons gained state monopolies for handmade paper, often decimating local independent producers. Yet prison and industrial officers counterintuitively positioned the frequent failures of papermaking experiments as a continuing potential source for industrial improvement. They argued that the failures demonstrated the need to improve discipline and supervision. Prison experiments slotted convicts into repetitive, mechanized roles that served European investigations into the utility of Indian products.


Asunto(s)
Colonialismo , India , Colonialismo/historia , Historia del Siglo XX , Prisiones/historia , Papel/historia , Historia del Siglo XXI , Industrias/historia , Humanos
13.
Lab Anim (NY) ; 53(5): 117-120, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38637688

RESUMEN

Many research groups explore the regulation of hibernation or compare the physiology of heterothermic mammals between the torpid and aroused, euthermic states. Current methods for monitoring torpor (for example, infrared cameras, body temperature or heart-rate telemetry, and motion sensing) are costly, require specialized techniques, and can be invasive. Here we present an alternate method for determining torpor-bout duration that is cost-effective, noninvasive and accurate: paper towel shredding. In the winter, euthermic thirteen-lined ground squirrels will shred paper towels placed in the cage, but torpid animals will not. The presence of a shredded paper towel, indicating an arousal from torpor, is easily evaluated during routine daily monitoring. In 12 animals over 52 days, this simple technique detected 59 arousals with 100% accuracy when compared with the body temperature telemetry of the same animals. Moreover, this novel method avoids some of the drawbacks of other cheap monitoring systems such as the sawdust technique.


Asunto(s)
Hibernación , Sciuridae , Animales , Sciuridae/fisiología , Hibernación/fisiología , Nivel de Alerta/fisiología , Telemetría/métodos , Telemetría/veterinaria , Temperatura Corporal , Masculino , Papel , Vivienda para Animales
14.
J Environ Manage ; 358: 120915, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38640753

RESUMEN

The demand for paper and paper-based packaging has seen a massive increase in past years, resulting in accelerated deforestation to meet the rising demand, negatively impacting the environment, and there is a need to look towards different non-woody raw materials. Kraft pulping (KP) is widely used in paper making, for which the chemical dose, temperature, time, and energy required must be optimized, for which many insignificant experimental trials are performed. An effort is made to solve this problem by developing the regression equations with the help of Excel using One Factor at a Time Analysis (OFAT), followed by carrying out design of experiments (DoE) using orthogonal approach and regression analysis in Minitab software. Life cycle Assessment (LCA) using the Open-LCA software estimates the effect of chemicals and energy required during pulping on human health, ecosystem quality, and resource depletion. Using regression analysis, the equations for predicting kappa number, yield (%), total energy consumed, and mechanical properties of the paper sheet showed a good fit with an R2 value in the range of 0.90-0.99. Apart from that, the mechanical properties, namely tensile index (41.43 Nm/g), tear index (6.96 mN m2/g), bending stiffness (0.5 mN m), and burst index (3.92 kPa m2/g) of the unbeaten sheet, were determined experimentally at optimized conditions. Based on the Open-LCA result, the optimized pulping conditions had less impact on human health, ecosystem quality, and resource depletion. Industries can use the model to predict the values of kappa number, yield, mechanical properties, and energy consumption without performing optimization experiments that may impact the industry's economy to a greater extent.


Asunto(s)
Papel , Triticum , Análisis de Regresión , Conservación de los Recursos Naturales
15.
Biosensors (Basel) ; 14(4)2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38667165

RESUMEN

The exploration into nanomaterial-based nonenzymatic biosensors with superb performance in terms of good sensitivity and anti-interference ability in disease marker monitoring has always attained undoubted priority in sensing systems. In this work, we report the design and synthesis of a highly active nanocatalyst, i.e., palladium and platinum nanoparticles (Pt&Pd-NPs) decorated ultrathin nanoporous gold (NPG) film, which is modified on a homemade graphene paper (GP) to develop a high-performance freestanding and flexible nanohybrid electrode. Owing to the structural characteristics the robust GP electrode substrate, and high electrochemically catalytic activities and durability of the permeable NPG support and ultrafine and high-density Pt&Pd-NPs on it, the resultant Pt&Pd-NPs-NPG/GP electrode exhibits excellent sensing performance of low detection limitation, high sensitivity and anti-interference capability, good reproducibility and long-term stability for the detection of small molecular biomarkers hydrogen peroxide (H2O2) and glucose (Glu), and has been applied to the monitoring of H2O2 in different types of live cells and Glu in body fluids such as urine and fingertip blood, which is of great significance for the clinical diagnosis and prognosis in point-of-care testing.


Asunto(s)
Biomarcadores , Técnicas Biosensibles , Técnicas Electroquímicas , Oro , Grafito , Nanopartículas del Metal , Paladio , Platino (Metal) , Grafito/química , Oro/química , Platino (Metal)/química , Paladio/química , Nanopartículas del Metal/química , Biomarcadores/orina , Humanos , Peróxido de Hidrógeno , Aleaciones/química , Glucosa/análisis , Electrodos , Papel
16.
Biosens Bioelectron ; 257: 116292, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38653014

RESUMEN

We report the development and initial validation of a paper-based nucleic acid testing platform that integrates Loop-mediated isothermal amplification (LAMP) with clustered regularly interspaced short palindromic repeats (CRISPR) technology, referred to as PLACID (Paper-based LAMP-CRISPR Integrated Diagnostics). LAMP eliminates the need for thermal cycling, resulting in simplified instrumentation, and the CRISPR-associated protein (Cas 12a) system eliminates false positive signals from LAMP products, resulting in highly selective and sensitive assays. We optimized the assay to perform both amplification and detection entirely on paper, eliminating the need for complex fluid handling steps and lateral flow assay transfers. Additionally, we engineered a smartphone-operated system that includes a low-powered, non-contact IR heating chamber to actuate paper-based LAMP and CRISPR reactions and enable the detection of fluorescent signals from the paper. The platform demonstrates high specificity and sensitivity in detecting nucleic acid targets with a limit of detection of 50 copies/µL. We integrate an equipment-free sample preparation separation technology designed to streamline the preparation of crude samples prior to nucleic acid testing. The practical utility of our platform is demonstrated by the successful detection of spiked SARS-CoV-2 RNA fragments in saliva, E. Coli in soil, and pathogenic E. Coli in clinically fecal samples of infected patients. Furthermore, we demonstrate that the paper-based LAMP CRISPR chips employed in our assays possess a shelf life of several weeks, establishing them as viable candidates for on-site diagnostics.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Sistemas CRISPR-Cas , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Papel , SARS-CoV-2 , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas de Amplificación de Ácido Nucleico/instrumentación , Humanos , Técnicas Biosensibles/métodos , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , COVID-19/diagnóstico , COVID-19/virología , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/instrumentación , Sistemas CRISPR-Cas/genética , Límite de Detección , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Diseño de Equipo , Prueba de Ácido Nucleico para COVID-19/métodos , Prueba de Ácido Nucleico para COVID-19/instrumentación , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Proteínas Asociadas a CRISPR/genética , Teléfono Inteligente
17.
Biosens Bioelectron ; 257: 116300, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38657378

RESUMEN

Developing simple, inexpensive, fast, sensitive, and specific probes for antibiotic-resistant bacteria is crucial for the management of urinary tract infections (UTIs). We here propose a paper-based sensor for the rapid detection of ß-lactamase-producing bacteria in the urine samples of UTI patients. By conjugating a strongly electronegative group -N+(CH3)3 with the core structures of cephalosporin and carbapenem antibiotics, two visual probes were achieved to respectively target the extended-spectrum/AmpC ß-lactamases (ESBL/AmpC) and carbapenemase, the two most prevalent factors causing antibiotic resistance. By integrating these probes into a portable paper sensor, we confirmed 10 and 8 cases out of 30 clinical urine samples as ESBL/AmpC- and carbapenemase-positive, respectively, demonstrating 100% clinical sensitivity and specificity. This paper sensor can be easily conducted on-site, without resorting to bacterial culture, providing a solution to the challenge of rapid detection of ß-lactamase-producing bacteria, particularly in resource-limited settings.


Asunto(s)
Técnicas Biosensibles , Papel , Infecciones Urinarias , beta-Lactamasas , beta-Lactamasas/metabolismo , beta-Lactamasas/química , Humanos , Infecciones Urinarias/microbiología , Infecciones Urinarias/diagnóstico , Técnicas Biosensibles/métodos , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Proteínas Bacterianas , Bacterias/aislamiento & purificación , Bacterias/enzimología , Cefalosporinas/química , Carbapenémicos/farmacología
18.
Int J Biol Macromol ; 267(Pt 1): 131539, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38608994

RESUMEN

Sustainable strategies to improve the water resistance of cellulose paper are actively sought. In this work, polymeric microspheres (PMs), prepared through emulsion polymerization of cellulose nanofibers stabilized rubber seed oil-derived monomer, were investigated as coatings on corrugated medium paper (CMP). After infiltrating porous paper with PMs, the water-resistant corrugated papers (WRCPn) with enhanced mechanical properties were obtained. When 30 wt% PMs were introduced, WRCP30 turned out to be highly compacted with an increased water contact angle of 106.3° and a low water vapor transmission rate of 81 g/(m2 d) at 23 °C. Meanwhile, the tensile strength of WRCP30 increased to 22.2 MPa, a 4-fold increase from CMP. When tested in a well-hydrated state, 71% of its mechanical strength in the dry state was maintained. Even with a low content of 10 wt% PMs, WRCP10 also exhibited stable tensile strength and water wettability during the cyclic soaking-drying process. Thus, the plant oil based sustainable emulsion polymers provide a convenient route for enhancing the overall performance of cellulose paper.


Asunto(s)
Celulosa , Microesferas , Aceites de Plantas , Resistencia a la Tracción , Agua , Celulosa/química , Agua/química , Aceites de Plantas/química , Papel , Humectabilidad , Polímeros/química , Emulsiones/química , Porosidad , Nanofibras/química
19.
Anal Bioanal Chem ; 416(13): 3139-3148, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38632131

RESUMEN

The rapid discrimination of bacteria is currently an emerging trend in the fields of food safety, medical detection, and environmental observation. Traditional methods often require lengthy culturing processes, specialized analytical equipment, and bacterial recognition receptors. In response to this need, we have developed a paper-based fluorescence sensor array platform for identifying different bacteria. The sensor array is based on three unique carbon quantum dots (CQDs) as sensing units, each modified with a different antibiotic (polymyxin B, ampicillin, and gentamicin). These antibiotic-modified CQDs can aggregate on the bacterial surface, triggering aggregation-induced fluorescence quenching. The sensor array exhibits varying fluorescent responses to different bacterial species. To achieve low-cost and portable detection, CQDs were formulated into fluorescent ink and used with an inkjet printer to manufacture paper-based sensor arrays. A smartphone was used to collect the responses generated by the bacteria and platform. Diverse machine learning algorithms were utilized to discriminate bacterial types. Our findings showcase the platform's remarkable capability to differentiate among five bacterial strains, within a detection range spanning from 1.0 × 103 CFU/mL to 1.0 × 107 CFU/mL. Its practicality is further validated through the accurate identification of blind bacterial samples. With its cost-effectiveness, ease of fabrication, and high degree of integration, this platform holds significant promise for on-site detection of diverse bacteria.


Asunto(s)
Bacterias , Carbono , Aprendizaje Automático , Papel , Puntos Cuánticos , Puntos Cuánticos/química , Carbono/química , Bacterias/aislamiento & purificación , Fluorescencia , Espectrometría de Fluorescencia/métodos , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Antibacterianos/análisis , Antibacterianos/farmacología , Algoritmos
20.
Bioresour Technol ; 401: 130744, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38677384

RESUMEN

Paper sludge biomass represents an underutilized feedstock rich in pulped and processed cellulose which is currently a waste stream with significant disposal cost to industry for landfilling services. Effective fractionation of the cellulose from paper sludge presents an opportunity to yield cellulose as feedstock for value-added processes. A novel approach to cellulose fractionation is the sidehill screening system, herein studied at the pilot-plant scale. Composition analysis determined ash removal and carbohydrate retention of both sidehill and high-performance benchtop screening systems. Sidehill screening resulted in greater carbohydrates retention relative to benchtop screening (90% vs 66%) and similar ash removal (95% vs 98%). Techno-economic analysis for production of sugar syrup yielded a minimum selling price of $331/metric ton of sugar syrup including disposal savings, significantly less than a commercial sugar syrup without fractionation. Sensitivity analysis showed that screening conditions played a significant role in economic feasibility for cellulosic yield and downstream processes.


Asunto(s)
Biomasa , Celulosa , Papel , Aguas del Alcantarillado , Proyectos Piloto , Celulosa/química , Fraccionamiento Químico
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