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1.
Anal Chem ; 95(16): 6690-6699, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-36961950

RESUMEN

Fully integrated wearable sensors are capable of dynamically, directly, and independently tracking biomarkers in raw noninvasive biofluids without any other equipment or accessories by integrating the unique on-body monitoring feature with the special complete functional implementation attribute. Sweat, saliva, and urine are three important noninvasive biofluids, and changes in their biomarkers hold great potential for revealing physiological conditions. However, it is still a challenge to design single fully integrated wearable sensor arrays (FIWSAs) that are universally able to concurrently measure electrolytes and metabolites in three of the most common noninvasive biofluids including sweat, saliva, and urine. Here, we propose the first single universal FIWSAs for wirelessly, noninvasively, and simultaneously measuring various metabolites (i.e., uric acid) and electrolytes (i.e., Na+ and H+) in raw sweat, saliva, or urine under subjects' exercise by integrating the specifically designed microfluidic, sensing, and electronic modules in a seamless manner. We evaluate its utility for noninvasive gout management in healthy subjects and in gout patients through a purine-rich meal challenge and with a medicine-treatment control, respectively. Noninvasive monitoring of multiple electrolytes and metabolites in a variety of raw noninvasive biofluids via such single universal FIWSAs may enrich the understanding of the biomarkers' levels in the body and would also facilitate self-health management.


Asunto(s)
Técnicas Biosensibles , Gota , Dispositivos Electrónicos Vestibles , Humanos , Sudor , Saliva , Monitoreo Fisiológico , Electrólitos , Biomarcadores
2.
Nanoscale ; 14(4): 1318-1326, 2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35013742

RESUMEN

The development of conductive bridging random access memory (CBRAM) as an artificial synaptic device is an important step in the realization of an efficient biomimetic neural morphology computing system. In fact, CBRAM devices with simple substance electrodes often form unstable and discrete conductive filaments, thereby resulting in poor device performance. In this work, the effects of different alloy electrode ratios on the performance of HfOx devices with dielectric layers were systematically investigated via electrode composition engineering. The devices (a kind of memristor) with an Ag-Cu ratio of 63 : 37 exhibited a lower formation voltage and set voltage, better set voltage distribution uniformity, faster response speed, and lower power consumption than other devices. Moreover, the device is capable of emulating the biosynapse functions, including paired-pulse facilitation (PPF), post-tetanic potentiation (PTP), spike-rate-dependent plasticity (SRDP), and spike-timing-dependent plasticity (STDP). Interestingly, the associative learning process of Pavlov's dog experiment and aversion therapy were also realized without the use of complex external circuits. The use of electrode component engineering provides a new path for boosting the memristor properties via CBRAM devices, thereby laying the foundation for further development of neural morphology computing systems.


Asunto(s)
Aleaciones , Plasticidad Neuronal , Animales , Perros , Conductividad Eléctrica , Electrodos , Sinapsis
3.
ACS Appl Mater Interfaces ; 12(46): 51249-51262, 2020 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-33161703

RESUMEN

Glucose oxidase (GOx)-mediated starvation therapy has demonstrated good application prospect in cancer treatment. However, the glucose- and oxygen-depletion starvation therapy still suffers from some limitations like low therapeutic efficiency and potential side effects to normal tissues. To overcome these disadvantages, herein a novel enzymatic cascade nanoreactor (Pd@Pt-GOx/hyaluronic acid (HA)) with controllable enzymatic activities was developed for high-efficiency starving-enhanced chemodynamic cancer therapy. The Pd@Pt-GOx/HA was fabricated by covalent conjugation of GOx onto Pd@Pt nanosheets (NSs), followed by linkage with hyaluronic acid (HA). The modification of HA on Pd@Pt-GOx could block the GOx activity, catalase (CAT)-like and peroxidase (POD)-like activities of Pd@Pt, reduce the cytotoxicity to normal cells and organs, and effectively target CD44-overexpressed tumors by active targeting and passive enhanced permeability and retention (EPR) effect. After endocytosis by tumor cells, the intracellular hyaluronidase (Hyase) could decompose the outer HA and expose Pd@Pt-GOx for the enzymatic cascade reaction. The GOx on the Pd@Pt-GOx could catalyze the oxidation of intratumoral glucose by O2 for cancer starvation therapy, while the O2 produced from the decomposition of endogenous H2O2 by the Pd@Pt with the CAT-like activity could accelerate the O2-dependent depletion of glucose by GOx. Meanwhile, the upregulated acidity and H2O2 content in the tumor region generated by GOx catalytic oxidation of glucose dramatically facilitated the pH-responsive POD-like activity of the Pd@Pt nanozyme, which then catalyzed degradation of the H2O2 to generate abundant highly toxic •OH, thereby realizing nanozyme-mediated starving-enhanced chemodynamic cancer therapy. In vitro and in vivo results indicated that the controllable, self-activated enzymatic cascade nanoreactors exerted highly efficient anticancer effects with negligible biotoxicity.


Asunto(s)
Materiales Biocompatibles/química , Glucosa Oxidasa/metabolismo , Ácido Hialurónico/química , Nanoestructuras/química , Paladio/química , Platino (Metal)/química , Animales , Apoptosis/efectos de los fármacos , Biocatálisis , Materiales Biocompatibles/farmacocinética , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/uso terapéutico , Línea Celular Tumoral , Glucosa/química , Glucosa/metabolismo , Glucosa Oxidasa/química , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/metabolismo , Concentración de Iones de Hidrógeno , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Ratones , Nanoestructuras/uso terapéutico , Nanoestructuras/toxicidad , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Oxígeno/química , Especies Reactivas de Oxígeno/metabolismo , Distribución Tisular , Trasplante Homólogo
4.
ACS Appl Mater Interfaces ; 11(20): 18654-18661, 2019 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-31038906

RESUMEN

As artificial synapses in biomimetics, memristors have received increasing attention because of their great potential in brain-inspired neuromorphic computing. The use of biocompatible and degradable materials as the active resistive layer is promising in memristor fabrication. In this work, we select egg albumen as the resistive layer to fabricate flexible tungsten/egg albumen/indium tin oxide/polyethylene terephthalate devices, which can operate normally under mechanical bending without significant performance degradation. This proposed memristor device exhibits a transparency of more than 90% under visible light with a wavelength range of 230-850 nm. Moreover, by changing amplitudes of pulse voltage instead of intervals, paired-pulse facilitation can be transmitted to paired-pulse depression, which can faithfully mimic dynamical balance of Ca2+ concentration shaped by voltage-sensitive calcium channels. The device resistance can be modulated gradually by applied pulse trains to mimic certain neural bionic behaviors, including excitatory postsynaptic current, short-term plasticity (STP) and long-term plasticity (LTP), and transitions between STP and LTP. The reasons behind these behaviors are analyzed through power consumption calculation. Excellent biosimulation characteristics have been demonstrated in this egg albumen-based memristor device, which is desirable in biocompatible and dissolvable electronics for flexible artificial neuromorphic systems.


Asunto(s)
Albúminas/química , Electrónica , Tereftalatos Polietilenos/química , Compuestos de Estaño/química , Tungsteno/química , Animales , Pollos
5.
Artículo en Inglés | MEDLINE | ID: mdl-26439523

RESUMEN

As complicated mixture systems, active components of Chuanxiong Rhizoma are very difficult to identify and discriminate. In this paper, the macroscopic IR fingerprint method including Fourier transform infrared spectroscopy (FT-IR), the second derivative infrared spectroscopy (SD-IR) and two-dimensional correlation infrared spectroscopy (2DCOS-IR), was applied to study and identify Chuanxiong raw materials and its different segmented production of HPD-100 macroporous resin. Chuanxiong Rhizoma is rich in sucrose. In the FT-IR spectra, water eluate is more similar to sucrose than the powder and the decoction. Their second derivative spectra amplified the differences and revealed the potentially characteristic IR absorption bands and combined with the correlation coefficient, concluding that 50% ethanol eluate had more ligustilide than other eluates. Finally, it can be found from 2DCOS-IR spectra that proteins were extracted by ethanol from Chuanxiong decoction by HPD-100 macroporous resin. It was demonstrated that the above three-step infrared spectroscopy could be applicable for quick, non-destructive and effective analysis and identification of very complicated and similar mixture systems of traditional Chinese medicines.


Asunto(s)
Medicamentos Herbarios Chinos/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/análisis , Porosidad , Resinas Sintéticas/química , Sacarosa/análisis
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