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1.
Heliyon ; 10(7): e28949, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38617934

RESUMO

Background: Prostate cancer (PCa) and benign prostatic hyperplasia (BPH) are prevalent conditions affecting a significant portion of the male population, particularly with advancing age. Traditional diagnostic methods, such as digital rectal examination (DRE) and prostate-specific antigen (PSA) tests, have limitations in specificity and sensitivity, leading to potential overdiagnosis and unnecessary biopsies. Significance: This study explores the effectiveness of 1H NMR urine metabolomics in distinguishing PCa from BPH and in differentiating various PCa grades, presenting a non-invasive diagnostic alternative with the potential to enhance early detection and patient-specific treatment strategies. Results: The study demonstrated the capability of 1H NMR urine metabolomics in detecting distinct metabolic profiles between PCa and BPH, as well as among different Gleason grade groups. Notably, this method surpassed the PSA test in distinguishing PCa from BPH. Untargeted metabolomics analysis also revealed several metabolites with varying relative concentrations between PCa and BPH cases, suggesting potential biomarkers for these conditions.

2.
Chempluschem ; 88(2): e202200426, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36700359

RESUMO

Originating from the concept of classical chemical gardens, a new field coined 'chemobrionics' has recently emerged. In the present work, two chemobrionic systems grown from a hydrogel/liquid interface at different time scales (for 1, 7, 14 or 28 days) were investigated, i. e., a calcium-based hydrogel with a phosphate counterion solution (Ca-gel) and a phosphate-based hydrogel with a calcium counterion solution (P-gel). The initial pH changes of the systems were investigated, and the obtained tubular structures were studied using optical microscopy, SEM, AFM, PXRD and TGA. One of the important findings is that the tubes obtained in the Ca-gel system were straight and long, which could be explained by the larger pH difference observed between the hydrogel and the counterion solution in this system (ΔpH∼2.1) compared to the P-gel system (ΔpH∼0). The Ca-gel structures remained overall more amorphous even though increased crystallinity was observed in both systems with increased time spent in counterion solution. Both systems contained hydroxyapatite phases, with additional calcite phases observed for the P-gel structures and traces of κ-carrageenan for the Ca-gel structures. Our study provides a promising method for controlling tubular macrostructures through adjusting the reaction conditions such as maturation time and pH.

3.
Biosens Bioelectron ; 219: 114810, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36272349

RESUMO

Electronic tongues (e-tongues) have been broadly employed in monitoring the quality of food, beverage, cosmetics, and pharmaceutical products, and in diagnosis of diseases, as the e-tongues can discriminate samples of high complexity, reduce interference of the matrix, offer rapid response. Compared to other analytical approaches using expensive and complex instrumentation as well as required sample preparation, the e-tongue is non-destructive, miniaturizable and on-site method with little or no preparation of samples. Even though e-tongues are successfully commercialized, their application in cancer diagnosis from urine samples is underestimated. In this review, we would like to highlight the various analytical techniques such as Raman spectroscopy, infrared spectroscopy, fluorescence spectroscopy, and electrochemical methods (potentiometry and voltammetry) used as e-tongues for urine analysis towards non-invasive cancer diagnosis. Besides, different machine learning approaches, for instance, supervised and unsupervised learning algorithms are introduced to analyze extracted chemical data. Finally, capabilities of e-tongues in distinguishing between patients diagnosed with cancer and healthy controls are highlighted.

4.
Adv Sci (Weinh) ; 9(34): e2203693, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36266981

RESUMO

The design and characterization of spatiotemporal nano-/micro-structural arrangement that enable real-time and wide-spectrum molecular analysis is reported and demonestrated in new horizons of biomedical applications, such as wearable-spectrometry, ultra-fast and onsite biopsy-decision-making for intraoperative surgical oncology, chiral-drug identification, etc. The spatiotemporal sesning arrangement is achieved by scalable, binder-free, functionalized hybrid spin-sensitive (<↑| or <↓|) graphene-ink printed sensing layers on free-standing films made of porous, fibrous, and naturally helical cellulose networks in hierarchically stacked geometrical configuration (HSGC). The HSGC operates according to a time-space-resolved architecture that modulate the mass-transfer rate for separation, eluation and detection of each individual compound within a mixture of the like, hereby providing a mass spectrogram. The HSGC could be used for a wide range of applictions, including fast and real-time spectrogram generator of volatile organic compounds during liquid-biopsy, without the need of any immunochemistry-staining and complex power-hungry cryogenic machines; and wearable spectrometry that provide spectral signature of molecular profiles emiited from skin in the course of various dietry conditions.


Assuntos
Imunoquímica , Análise Espectral
5.
Anal Chim Acta ; 1221: 340114, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35934355

RESUMO

Electronic tongues (e-tongues) are analytical technologies that mimic the biological tongues which are non-specific, low-selective, and cross-sensitive taste systems. The e-tongues consist of an array of sensors, being able to produce electrical signals that correspond to particular chemical compositions of a sample solution. The performance and efficiency of e-tongues have been optimized for many years via the development of novel materials and technologies. Various conjugated polymers (CPs) have been used in e-tongues over the past decades thanks to their fascinating electrical properties and wide-ranging chemistries. In most studies, CPs such as polypyrrole (PPy), polyaniline (PANI), polythiophene (PT), and poly(3,4-ethylenedioxythiophene) (PEDOT), have drawn considerable interest in e-tongues because of their controllable electrical properties, relatively facile and cost-effective preparation, and good environmental stability that can significantly enhance their versatility, compared to other types of e-tongues. This review article reports major conjugated polymer-based e-tongues (CPETs) that have been studied with these aforementioned CPs over the last two decades.


Assuntos
Polímeros , Pirróis , Nariz Eletrônico , Polímeros/química , Pirróis/química
6.
Int J Biol Macromol ; 206: 105-114, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35219779

RESUMO

A novel conjugation of guar gum with xanthate groups via facile aqueous xanthation reaction has been reported. Density of grafted xanthate on guar gum product (GG-X) is as high as 4.4%, thus GG-X is conceivably characterized and confirmed by various spectrometric, electrochemical, thermogravimetric, and microscopic methods. Complexation of GG-X with numerous borderline and soft metal ions (e.g. Fe2+, Co2+, Ni2+, Cu2+, Pb2+, Pt2+ and Cd2+) yields hydrophilic gel-like materials and shows good agreement with hard and soft acid and base (HSAB) theory. This indicates tremendous potential of GG-X in metal ion extraction, removal and hydrogel cross-linking. GG-X is also employed to formulate an aqueous colloidal dispersion of copper sulfide covellite (GG-X/CuS) nanocomposites. GG-X therefore behaves as a surfactant, allowing formation of electronically conductive nanocomposites. XRD indicates apparent beneficial effects of GG-X in the synthesis of CuS with a crystallite size of 15.6 nm. This novel nanocomposite is a promising material for humidity sensing, showing reversible linear responses to relative humidity changes within 10 to 80% range. The interaction between GG-X and water might cause changes in electrical permittivity of GG-X/CuS nanocomposite and/or electrical hopping conductivity between CuS nanoparticles.


Assuntos
Cobre , Nanocompostos , Cobre/química , Galactanos/química , Umidade , Mananas/química , Metais , Nanocompostos/química , Gomas Vegetais/química , Sulfetos , Água
7.
Int J Biol Macromol ; 194: 110-116, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34861275

RESUMO

A novel chemical functionalization of guar gum (GG) by benzoic acid (BA) via nucleophilic substitution reaction in aqueous solution has been reported. BA moieties are chosen due to coordination chemistry of carboxylic acid moieties, hydrophobicity and intermolecular interaction of aromatic rings. The presence of conjugated BA on guar gum-benzoic acid (GG-BA) with grafting density of 5.5% is confirmed by 1H NMR. Amorphous GG-BA with irregular morphology has been studied by UV-Vis, FTIR, XRD, SEM, TEM, TGA, computational chemistry and contact angle measurement. GG-BA in a concentration range from 0 to 4000 µg mL-1 has good biocompatibility to mouse embryonic fibroblasts (MEF), human mammary epithelial cells (MCF-10A) after 48 and 72 h of treatment using WST-1 assay. GG-BA shows great potential for the development of biomaterials such as bioadhesives, hydrogels, and coacervates.


Assuntos
Ácido Benzoico/química , Materiais Biocompatíveis/química , Galactanos/química , Mananas/química , Gomas Vegetais/química , Animais , Ácido Benzoico/síntese química , Materiais Biocompatíveis/síntese química , Técnicas de Química Sintética , Humanos , Camundongos , Modelos Moleculares , Estrutura Molecular , Análise Espectral , Termodinâmica
8.
Foods ; 10(5)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069511

RESUMO

Innovative active packaging has the potential to maintain the food quality and preserve the food safety for extended period. The aim of this study was to discover the effect of active films based on commercially available polylactic acid blend (PLAb) and natural active components on the shelf life and organoleptic properties of chicken fillets and to find out; to what extent they can be used as replacement to the traditional packaging materials. In this study, commercially available PLAb was compounded with citral and cinnamon oil. Active films with 300 µm thickness were then produced on a blown film extruder. The PLAb-based films were thermoformed into trays. Fresh chicken breast fillets were packed under two different gas compositions, modified atmosphere packaging of 60% CO2/40% N2, and 75% O2/25% CO2 and stored at 4 °C. The effect of active packaging materials and gas compositions on the drip loss, dry matter content, organoleptic properties, and microbial quality of the chicken fillets were studied over a storage time of 24 days. The presence of active components in the compounded films was confirmed with FTIR, in addition the release of active components in the headspace of the packaging was established with GC/MS. Additionally, gas barrier properties of the packages were studied. No negative impact on the drip loss and dry matter content was observed. The results show that PLAb-based active packaging can maintain the quality of the chicken fillets and have the potential to replace the traditional packaging materials, such as APET/PE trays.

9.
J Chem Educ ; 97(10): 3702-3706, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33071310

RESUMO

The electrolysis of water is popular both as lab work and as a demonstration. In this activity, the electrolysis of water in the presence of a pH indicator is used to produce text and symbols. This report describes the design of an environmentally friendly setup of a writing board utilizing the electrolysis of water in a hydrogel environment. The activity can be performed by only using chemicals and materials that are easily accessible to everyone, with no special permit needed. The writing board has been developed mainly as an outreach activity for our faculty and has been assessed during visits from upper secondary school students.

10.
Nat Commun ; 10(1): 1120, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30850600

RESUMO

Recent years have witnessed thriving progress of flexible and portable electronics, with very high demand for cost-effective and tailor-made multifunctional devices. Here, we report on an ingenious origami hierarchical sensor array (OHSA) written with a conductive ink. Thanks to origami as a controllable hierarchical framework for loading ink material, we have demonstrated that OHSA possesses unique time-space-resolved, high-discriminative pattern recognition (TSR-HDPR) features, qualifying it as a smart sensing device for simultaneous sensing and distinguishing of complex physical and chemical stimuli, including temperature, relative humidity, light and volatile organic compounds (VOCs). Of special importance, OSHA has shown very high sensitivity in differentiating between structural isomers and chiral enantiomers of VOCs - opening a door for wide variety of unique opportunities in several length scales.

11.
Small ; 15(2): e1803939, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30548393

RESUMO

A flexible and stretchable field-effect transistor (FET) is an essential element in a number of modern electronics. To realize the potential of this device in harsh real-world conditions and to extend its application spectrum, new functionalities are needed to be introduced into the device. Here, solution-processable elements based on carbon nanotubes that empower flexible and stretchable FET with high hole-mobility (µh ≈ 10 cm2 V-1 s-1 ) and relatively low operating voltages (<8 V) and that retain self-healing properties of all FET components are reported. The device has repeatable intrinsic and autonomic self-healing ability, namely without use of any external trigger, enabling the restoration of its electrical and mechanical properties, both after microscale damage or complete cut of the device-for example by a scissor. The device can be repeatedly stretched for >200 cycles of up to 50% strain without a significant loss in its electrical properties. The device is applicable in the form of a ≈3 µm thick freestanding skin tattoo and has multifunctional sensing properties, such as detection of temperature and humidity. With this unprecedented biomimetic transistor, highly sustainable and reliable soft electronic applications can be introduced.

12.
Adv Mater ; 30(50): e1802337, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30073703

RESUMO

A concise, although admittedly non-exhaustive, didactic summary is given of some of the main concepts and approaches related to recent advances and developments to enable autonomous detection and monitoring of the likelihood or existence of a health risk state in continuous and real-time modes. To give a comprehensive statement, different aspects of these advanced materials and related devices are presented and discussed, such as: flexible sensors used for non-invasive detection of health-related physiological markers; self-powered materials to enable extended usage periods by harvesting energy from body movement and temperature; and self-healing properties of the materials used on the wearable devices to enable extended usage periods if scratched or cut. The linkage of these advanced materials and technologies together is particularly specified. Some of the strong and weak points in the development of each wearable material/device are clearly highlighted and criticized. Several ideas regarding further improvement of skin-based wearable devices are also discussed.


Assuntos
Monitorização Fisiológica/métodos , Dispositivos Eletrônicos Vestíveis , Temperatura Corporal , Frequência Cardíaca , Humanos , Monitorização Fisiológica/instrumentação , Nanofios , Pele/metabolismo
13.
ChemSusChem ; 11(16): 2654-2672, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-29944207

RESUMO

Because 100 % quantum efficiency for the photosynthetic production of H2 from H2 O under visible illumination has been achieved recently, the oxidation of H2 O to O2 remains the bottleneck to the overall water-splitting reaction. Oxidation of CH4 to CH3 OH might be combined with water reduction instead, so that H2 and CH3 OH chemical fuels can be simultaneously produced through a one-step process under solar illumination. This combination would be a promising approach towards a more sustainable future of chemistry, in which developing different strategies for artificial photosynthesis is of paramount importance. By using free and adsorbed HO. radicals on the semiconductor surface, CH4 can be activated to H3 C. radicals and converted into CH3 OH, respectively, with great selectivity up to 100 %. The present lack of efficient photosynthetic systems for the formation of H2 and CH3 OH from abundant H2 O and CH4 motivates future research for basic science and industrial applications.

14.
Adv Mater ; 29(19)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28229499

RESUMO

Devices integrated with self-healing ability can benefit from long-term use as well as enhanced reliability, maintenance and durability. This progress report reviews the developments in the field of self-healing polymers/composites and wearable devices thereof. One part of the progress report presents and discusses several aspects of the self-healing materials chemistry (from non-covalent to reversible covalent-based mechanisms), as well as the required main approaches used for functionalizing the composites to enhance their electrical conductivity, magnetic, dielectric, electroactive and/or photoactive properties. The second and complementary part of the progress report links the self-healing materials with partially or fully self-healing device technologies, including wearable sensors, supercapacitors, solar cells and fabrics. Some of the strong and weak points in the development of each self-healing device are clearly highlighted and criticized, respectively. Several ideas regarding further improvement of soft self-healing devices are proposed.

15.
ACS Appl Mater Interfaces ; 9(4): 3948-3958, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28071057

RESUMO

A new strategy of simple, inexpensive, rapid, and label-free single-nucleotide-polymorphism (SNP) detection using robust chemosensors with piezomicrogravimetric, surface plasmon resonance, or capacitive impedimetry (CI) signal transduction is reported. Using these chemosensors, selective detection of a genetically relevant oligonucleotide under FIA conditions within 2 min is accomplished. An invulnerable-to-nonspecific interaction molecularly imprinted polymer (MIP) with electrochemically synthesized probes of hexameric 2,2'-bithien-5-yl DNA analogues discriminating single purine-nucleobase mismatch at room temperature was used. With density functional theory modeling, the synthetic procedures developed, and isothermal titration calorimetry quantification, adenine (A)- or thymine (T)-substituted 2,2'-bithien-5-yl functional monomers capable of Watson-Crick nucleobase pairing with the TATAAA oligodeoxyribonucleotide template or its peptide nucleic acid (PNA) analogue were designed. Characterized by spectroscopic techniques, molecular cavities exposed the ordered nucleobases on the 2,2'-bithien-5-yl polymeric backbone of the TTTATA hexamer probe designed to hybridize the complementary TATAAA template. In that way, an artificial TATAAA-promoter sequence was formed in the MIP. The purine nucleobases of this sequence are known to be recognized by RNA polymerase to initiate the transcription in eukaryotes. The hexamer strongly hybridized TATAAA with the complex stability constant KsTTTATA-TATAAA = ka/kd ≈ 106 M-1, as high as that characteristic for longer-chain DNA-PNA hybrids. The CI chemosensor revealed a 5 nM limit of detection, quite appreciable as for the hexadeoxyribonucleotide. Molecular imprinting increased the chemosensor sensitivity to the TATAAA analyte by over 4 times compared to that of the nonimprinted polymer. The herein-devised detection platform enabled the generation of a library of hexamer probes for typing the majority of SNP probes as well as studying a molecular mechanism of the complex transcription machinery, physics of single polymer molecules, and stable genetic nanomaterials.

16.
Adv Mater ; 28(21): 4163, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27246920

RESUMO

An ambipolar organic field-effect transistor (OFET) based on poly(diketopyrrolopyrrole-terthiophene) (PDPPHD-T3) is shown by P. Sonar, H. Haick, and co-workers on page 4012 to sensitively detect xylene isomers at low to 40 ppm level in multiple sensing features. Combined with pattern-recognition algorithms, a sole ambipolar FET sensor, rather than arrays of sensors, is able to discriminate highly similar xylene structural isomers from each other.

17.
Nano Lett ; 16(7): 4194-202, 2016 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-27328179

RESUMO

Flexible and wearable electronic sensors are useful for the early diagnosis and monitoring of an individual's health state. Sampling of volatile organic compounds (VOCs) derived from human breath/skin or monitoring abrupt changes in heart-beat/breath rate should allow noninvasive monitoring of disease states at an early stage. Nevertheless, for many reported wearable sensing devices, interaction with the human body leads incidentally to unavoidable scratches and/or mechanical cuts and bring about malfunction of these devices. We now offer proof-of-concept of nanoparticle-based flexible sensor arrays with fascinating self-healing abilities. By integrating a self-healable polymer substrate with 5 kinds of functionalized gold nanoparticle films, a sensor array gives a fast self-healing (<3 h) and attractive healing efficiency in both the substrate and sensing films. The proposed platform was used in sensing pressure variation and 11 kinds of VOCs. The sensor array had satisfactory sensitivity, a low detection limit, and promising discrimination features in monitoring both of VOCs and pressure variation, even after full healing. These results presage a new type of smart sensing device, with a desirable performance in the possible detection and/or clinical application for a number of different purposes.


Assuntos
Testes Respiratórios/instrumentação , Nanopartículas Metálicas , Pele/química , Compostos Orgânicos Voláteis/análise , Dispositivos Eletrônicos Vestíveis , Ouro , Humanos
18.
Adv Mater ; 28(21): 4012-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26996398

RESUMO

An ambipolar poly(diketopyrrolopyrrole-terthiophene)-based field-effect transistor (FET) sensitively detects xylene isomers at low ppm levels with multiple sensing features. Combined with pattern-recognition algorithms, a sole ambipolar FET sensor, rather than arrays of sensors, can discriminate highly similar xylene structural isomers from one another.

19.
J Mater Chem B ; 4(6): 1156-1165, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32263008

RESUMO

A chemosensor with a molecularly imprinted polymer (MIP) film as the recognition unit selective to a carnosine biomarker was molecularly engineered, devised and fabricated. The molecular structure of the pre-polymerization complex of the carnosine template with the carboxy and 18-crown-6 ether derivatives of bis(2,2'-bithien-5-yl)methane functional monomers was thermodynamically optimized by density functional theory (DFT) at the B3LYP/6-31g(d) level. The calculated high negative Gibbs free energy change, ΔG = -227.4 kJ mol-1, indicated the formation of a very stable complex. The solution of this complex was prepared and used for deposition of the MIP films on a Pt disk electrode or an Au electrode of the quartz crystal resonator by potentiodynamic electropolymerization. Subsequently, the carnosine template was extracted from the MIPs with 0.1 M NaOH, as confirmed by the differential pulse voltammetry (DPV), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy measurements. For carnosine sensing, impedimetric capacity (IC) measurements were performed under flow-injection analysis (FIA) conditions resulting in the limit of detection of 20 µM (at S/N = 3). This limit implied the readiness of the chemosensor for carnosine determination in clinical samples. Due to multiple modes of carnosine binding to MIP recognition sites, the IC chemosensor was found to be more selective to carnosine than to its common interferences including anserine, carcinine and histidine. Advantageously, the imprinting factor, determined by piezoelectric microgravimetry (PM), was high equaling 14.9.

20.
Adv Mater ; 28(1): 138-43, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26551539

RESUMO

A non-biological and flexible self-healing platform has tailored sensitivity toward one or a combination of pressure, strain, gas analytes, and temperature. For demonstration, a complete self-healing device is described in the form of a bendable and stretchable chemiresistor, where every part is self-healing.

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