Abstract: Exposure to widely used inert fibrous nanomaterials (e.g., glass fibers, carbon nanotubes) might result in asbestos-like lung pathologies, becoming an important environmental and health concern. However, the origin of the pathogenesis of such fibers has not yet been clearly established. Here, we report on an electrochemical nanosensor which is used to monitor and quantitatively characterize ...
ABSTRACT: Reactive oxygen and nitrogen species (ROS/RNS) are generated by macrophages inside their phagolysosomes. This production is essential for phagocytosis of damaged cells and pathogens, i.e., protecting the organism and maintaining immune homeostasis. The ability to quantitatively and individually monitor the four primary ROS/RNS (ONOO–, H2O2, NO, and NO2–) with submillisecond resolution is clearly warranted to elucidate the still unclear mechanisms of their rapid generation and to track their concentration variations over time inside phagolysosomes, in particular, to document the origin of ROS/RNS homeostasis during phagocytosis. A novel nanowire electrode has been specifically developed for this purpose. It consisted of wrapping a SiC nanowire with a mat of 3 nm platinum nanoparticles whose high electrocatalytic performances allow the characterization and individual measurements of each of the four primary ROS/RNS.
Abstract: Glutamate (Glu) is the major excitatory transmitter in the nervous system. Impairment of its vesicular release by β-amyloid (Aβ) oligomers is thought to participate in pathological processes leading to Alzheimer’s disease. However, it remains unclear whether soluble Aβ42 oligomers affect intravesicular amounts of Glu or their release in the brain, or both. Measurements made in this work ...
ABSTRACT: Rare circulating tumor cells (CTCs) are always harvested with large numbers of white blood cells (WBCs) by current CTC isolation techniques, which influences the accuracy of CTC-related gene and protein analysis. Therefore, it is very urgent to develop a method for efficient isolation of CTCs with high purity. In this work, we fabricated a reversibly assembled interface by layer-by-layer assembly of biotinylated poly-(L-lysine-graft-ethylene glycol) (PLL-g-PEG-biotin), streptavidin, and CTC-specific antibody on a three-dimensional conductive scaffold, and further embedded it into a customized microchip for CTC capture. The assembled multilayers increased the roughness of the scaffold, which improved the capture efficiency.
ABSTRACT: Rare circulating tumor cells (CTCs) are always harvested with large numbers of white blood cells (WBCs) by current CTC isolation techniques, which influences the accuracy of CTC-related gene and protein analysis. Therefore, it is very urgent to develop a method for efficient isolation of CTCs with high purity. In this work, we fabricated a reversibly assembled interface by layer-by-layer assembly of biotinylated poly-(L-lysine-graft-ethylene glycol) (PLL-g-PEG-biotin), streptavidin, and CTC-specific antibody on a three-dimensional conductive scaffold, and further embedded it into a customized microchip for CTC capture. The assembled multilayers increased the roughness of the scaffold, which improved the capture efficiency.
ABSTRACT: Reactive oxygen species (ROS) and nicotinamide adenine dinucleotide (NADH) are important intracellular redoxactive molecules involved in various pathological processes including inflammation, neurodegenerative diseases, and cancer. However, the fast dynamic changes and mutual regulatory kinetic relationship between intracellular ROS and NADH in these biological processes are still hard to simultaneously investigate. A dual-channel nanowire electrode (DC-NWE) integrating two conductive nanowires, one functionalized with platinum nanoparticles and the other with conductive polymer, was nanofabricated for the selective and simultaneous real-time monitoring of intracellular ROS and NADH release by mitochondria in single living MCF-7 tumoral cells stimulated by resveratrol. The production of ROS was observed to occur tenths of a second before the release of NADH, a significant new piece of information suggesting a mechanism of action of resveratrol.
ABSTRACT:Many cells in vivo have their inherent motions, which involve numerous biochemical and biophysical signals synergistically regulating cell behaviors and functions. However, existing methods offer little information about the concurrently chemical and physical responses of dynamically pulsing cells. Here, we report a soft electrode with electrospun poly(3,4-ethylenedioxythiophene) (PEDOT)-based nanomesh to fully comply with spontaneous motions of cells......
ABSTRACT:The current strategies for nanoelectrode functionalization usually involve sophisticated modification procedures, uncontrollable and unstable modifier assembly, as well as a limited variety of modifiers. To address this issue, we propose a versatile strategy for large-scale synthesis of biomimetic molecular catalysts (BMCs) modified nanowires (NWs) to construct functionalized electr...