A sensor for uric acid (UA) based on the urate oxidase enzyme (UOx) immobilized in novel Co-based aerogels with transition metals synthesized by the sol-gel method was developed and evaluated. The Co-based aerogels: Co, Ni-Co and Pd-Co were physicochemically characterized by XRD and HR-TEM. The surface area values of 53, 57 and 66 m g-1 were determined for Co, Ni-Co and Pd-Co, respectively by N adsorption-desorption technique.
View Article and Find Full Text PDFCuZnSnS (CZTS) was synthesized following hot injection method and the process was optimized by varying temperature conditions. Four samples at different temperatures viz., 200, 250, 300 and 350 °C were prepared and analyzed using different characterization techniques.
View Article and Find Full Text PDFThe biophysical properties of lipid vesicles are important for their stability and integrity, key parameters that control the performance when these vesicles are used for drug delivery. The vesicle properties are determined by the composition of lipids used to form the vesicle. However, for a given lipid composition, they can also be tailored by tethering polymers to the membrane.
View Article and Find Full Text PDFDrop-cast crosslinked hydrogels are a common platform for enzymatic electrochemical biosensors. Despite the widespread use of these complex systems, there are still several questions about how their physicochemical properties affect their performance, stability, and reproducibility. In this work, first-generation faradaic biosensors composed of glucose oxidase and branched polyethyleneimine (BPEI) are prepared using either glutaraldehyde (GA) or ethylene glycol diglycidyl ether (EGDGE) as crosslinkers.
View Article and Find Full Text PDFThis article provides an overview of the work reported in the past decade in the field of microfluidic fuel cells. To develop appropriate research, the most commonly used electrocatalytic materials were considered and a new classification was proposed based on their nature: abiotic, hybrid, or biological. This classification allowed the authors to discern the information collected.
View Article and Find Full Text PDFBiosensors (Basel)
November 2023
In this work, a microfluidic prototype based on polymeric materials was developed to monitor surface processes using surface-enhanced Raman spectroscopy (SERS), keeping the reagents free of environmental contamination. The prototype was fabricated on poly(methyl methacrylic acid) (PMMA). A micrometric membrane of a functional organic polymer (FOP) based on -terphenyl and bromopyruvic acid monomers was formed on the PMMA surface to promote the formation of metal nanoclusters.
View Article and Find Full Text PDFInt J Mol Sci
August 2023
Zinc ferrite nanoparticles (ZFO NPs) are a promising magneto-crystalline platform for nanomedicine-based cancer theranostics. ZFO NPs synthesized using co-precipitation method are characterized using different techniques. UV-visible spectroscopy exhibits absorption peaks specific for ZFO.
View Article and Find Full Text PDFAn aqueous two-phase system (ATPS) encapsulated within a vesicle organizes the vesicle core as two coexisting phases that partition encapsulated solutes. Here, we use microfluidic technologies to produce vesicles that efficiently encapsulate mixtures of macromolecules, providing a versatile platform to determine the phase behavior of ATPSs. Moreover, we use compartmentalized vesicles to investigate how membrane permeability affects the dynamics of the encapsulated ATPS.
View Article and Find Full Text PDFThe inclusion of online, in situ biosensors in microfluidic cell cultures is important to monitor and characterize a physiologically mimicking environment. This work presents the performance of second-generation electrochemical enzymatic biosensors to detect glucose in cell culture media. Glutaraldehyde and ethylene glycol diglycidyl ether (EGDGE) were tested as cross-linkers to immobilize glucose oxidase and an osmium-modified redox polymer on the surface of carbon electrodes.
View Article and Find Full Text PDFEvaluating the fitness of hybrids can provide important insights into genetic differences between species or diverging populations. We focused on surface- and cave-ecotypes of the widespread Atlantic molly and raised F1 hybrids of reciprocal crosses to sexual maturity in a common-garden experiment. Hybrids were reared in a fully factorial 2 × 2 design consisting of lighting (light vs.
View Article and Find Full Text PDFThis work reports on FeO and ZnO materials for lactate quantification. In the synthesis, the bi-phase γ-/α-FeO and γ-/α-FeO/ZnO nanoparticles (NPs) were obtained for their application in a lactate colorimetric sensor. The crystalline phases of the NPs were analyzed by XRD and XPS techniques.
View Article and Find Full Text PDFFerrocene-based polymers as redox mediators are considered versatile and important in the study of glucose biosensors. Poly-L-lysine (PLL), as a cationic polymer, possesses good properties including biocompatibility, biodegradation and water solubility. In this work, PLL was modified with ferrocene carboxylate in a very simple way by activating the carboxyl group of Fc, which reacted with the amino groups of the polymer.
View Article and Find Full Text PDFIn this work, unsupported Pd aerogel catalysts were synthesized for the very first time by using microwaves as a heating source followed by a lyophilization drying process and used towards formic acid electro-oxidation in a microfluidic fuel cell. Aerogels were also made by heating in a conventional oven to evaluate the microwave effect during the synthesis process of the unsupported Pd aerogels. The performance of the catalysts obtained by means of microwave heating favored the formic acid electro-oxidation with HSO as the electrolyte.
View Article and Find Full Text PDFMetal sulfide nanoparticles are semi-conductors that possess many applications in optics, optoelectronics and magnetic devices. There are physical and chemical methods for their synthesis but such methods involve toxic precursors as well as many obnoxious by-products. Hence, biological synthesis of metal sulfide nanoparticles are efficient enough to transform toxic metals to non-toxic ones.
View Article and Find Full Text PDFIn this work, atomically substituted three-dimensionally ordered macroporous (3DOM) spinels based on Co and Mn (MnCoO and CoMnO) were synthetized and used as cathodic electrocatalysts in a primary Zn-air battery. Scanning/transmission electron microscopy images show a 3DOM structure for both materials. Skeleton sizes of 114.
View Article and Find Full Text PDFMagnetic nanoparticles such as cobalt ferrite are investigated under clinical hyperthermia conditions for the treatment of cancer. Cobalt ferrite nanoparticles (CFNPs) synthesized by the thermal decomposition method, using nonionic surfactant Triton-X100, possess hydrophilic polyethylene oxide chains acting as reducing agents for the cobalt and iron precursors. The monodispersed nanoparticles were of 10 nm size, as confirmed by high-resolution transmission electron microscopy (HR-TEM).
View Article and Find Full Text PDFIn this work, the proof of concept of a functional membraneless microfluidic Zn-air cell (μZAC) that operates with a flow-through arrangement is presented for the first time, where the activity and durability can be modulated by electrodepositing Zn on porous carbon electrodes. For this purpose, Zn electrodes were obtained using chronoamperometry and varying the electrodeposition times (20, 40, and 60 min), resulting in porous electrodes with Zn thicknesses of 3.3 ± 0.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 2020
Int J Environ Res Public Health
March 2020
Triple-negative breast cancer (TNBC) cells are deficient in estrogen, progesterone and ERBB2 receptor expression, presenting a particularly challenging therapeutic target due to their highly invasive nature and relatively low response to therapeutics. There is an absence of specific treatment strategies for this tumor subgroup, and hence TNBC is managed with conventional therapeutics, often leading to systemic relapse. In terms of histology and transcription profile these cancers have similarities to BRCA-1-linked breast cancers, and it is hypothesized that BRCA1 pathway is non-functional in this type of breast cancer.
View Article and Find Full Text PDFThe aim of this work is the evaluation of a Sulfonated Poly Ether-Ether Ketone (S-PEEK) polymer modified by the addition of pure Santa Barbara Amorphous-15 (SBA-15, mesoporous silica) and SBA-15 previously impregnated with phosphotungstic acid (PWA) fillers (PWA/SBA-15) in order to prepare composite membranes as an alternative to conventional Nafion membranes. This component is intended to be used as an electrolyte in electrochemical energy systems such as hydrogen and methanol Proton Exchange Membrane Fuel Cell (PEMFC) and Electrochemical Hydrogen Pumping (EHP). The common requirements for all the applications are high proton conductivity, thermomechanical stability, and fuel and oxidant impermeability.
View Article and Find Full Text PDFAsymmetric vesicles are membranes in which amphiphiles are asymmetrically distributed between each membrane leaflet. This asymmetry dictates chemical and physical properties of these vesicles, enabling their use as more realistic models of biological cell membranes, which also are asymmetric, and improves their potential for drug delivery and cosmetic applications. However, their fabrication is difficult as the self-assembly of amphiphiles always leads to symmetric vesicles.
View Article and Find Full Text PDFSeed-mediated Gold-Iron oxide yolk-shell nanoparticles (YSNPs) were synthesized and functionalized with cy5 attached- thiolated single strand DNA probe for the detection of mutated DNA. The optimum concentration of thiolated DNA determined from a bathochromic shift of surface plasmon resonance (SPR) peak, was 0.177μM.
View Article and Find Full Text PDFHybrid lipid/nanoparticle membranes are suitable model systems both to study the complex interactions between nanoparticles and biological membranes, and to demonstrate technological concepts in cellular sensing and drug delivery. Unfortunately, embedding nanoparticles into the bilayer membrane of lipid vesicles is challenging due to the poor control over the vesicle fabrication process of conventional methodologies and the fragility of the modified lipid bilayer assembly. Here, the utility of water-in-oil-in-water double emulsion drops with ultrathin oil shells as templates to form vesicles with hybrid lipid/nanoparticle membranes is reported.
View Article and Find Full Text PDFHybrid inorganic-organic Nafion membranes modified with metal oxides (typically TiO, ZrO, WO) are a good alternative for fuel cell applications. However, one of their main limitations is associated with their relative low proton conductivity at temperatures above 80 °C. In this work, we overcome this issue using HfO as a filler.
View Article and Find Full Text PDFTitanium oxide nanotubes (TNTs) were anodically grown in ethylene glycol electrolyte. The influence of the anodization time on their physicochemical and photoelectrochemical properties was evaluated. Concomitant with the anodization time, the NT length, fluorine content, and capacitance of the space charge region increased, affecting the opto-electronic properties (bandgap, bathochromic shift, band-edge position) and surface hydrophilicity of TiO NTs.
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