Aβ Oligomers Induced a Short-Term Increase of Glutamate Release Prior to Its Depletion As Measured by Amperometry on Single Varicosities.

Glutamate (Glu) is a critical neurotransmitter for neuronal communication in the nervous system. In vivo studies have shown that the concentration of Glu is reduced within the brains of those afflicted with Alzheimer's disease (AD), which is also associated with the accumulation of pathogenic amyloid-beta (Aβ). However, the effects of Aβ peptides on the level of Glu release, as well as how Aβ-mediated Glu fluctuation is initiated, remain largely unknown.

A single nanowire sensor for intracellular glucose detection.

Glucose metabolism plays an important role in cell energy supply, and quantitative detection of the intracellular glucose level is particularly important for understanding many physiological processes. Glucose electrochemical sensors are widely used for blood and extracellular glucose detection. However, intracellular glucose detection cannot be achieved by these sensors owing to their large size and consequent low spatial resolution.

Electrochemical Monitoring of ROS/RNS Homeostasis Within Individual Phagolysosomes Inside Single Macrophages.

The existence of a homeostatic mechanism regulating reactive oxygen/nitrogen species (ROS/RNS) amounts inside phagolysosomes has been invoked to account for the efficiency of this process but could not be unambiguously documented. Now, intracellular electrochemical analysis with platinized nanowire electrodes (Pt-NWEs) allowed monitoring ROS/RNS effluxes with sub-millisecond resolution from individual phagolysosomes impacting onto the electrode inserted inside a living macrophage. This shows for the first time that the consumption of ROS/RNS by their oxidation at the nanoelectrode surface stimulates the production of significant ROS/RNS amounts inside phagolysosomes.

Flexible Electrochemical Urea Sensor Based on Surface Molecularly Imprinted Nanotubes for Detection of Human Sweat.

Flexible electrochemical (EC) sensors have shown great prospect in epidermal detection for personal healthcare and disease diagnosis. However, no reports have been seen in flexible device for urea analysis in body fluids. Herein, we developed a flexible wearable EC sensor based on surface molecularly imprinted nanotubes for noninvasive urea monitoring with high selectivity in human sweat.

Detection of exosomes by ZnO nanowires coated three-dimensional scaffold chip device.

Exosomes as cell-derived vesicles have the potential to be novel biomarkers for noninvasive diagnosis of cancers. However, cost-effective detection of exosomes in routine clinical settings is still challenging. Herein, we present a ZnO nanowires coated three-dimensional (3D) scaffold chip device for effective immunocapture and classically visible and colorimetric detection of exosomes.

Quantifying orientational regeneration of injured neurons by natural product concentration gradients in a 3D microfluidic device.

Regeneration of injured neurons in complicated three-dimensional (3D) microenvironments is a key approach for treating neurodegenerative diseases. Microfluidics provides a versatile tool to recapitulate cellular microenvironments in vitro, but it still remains a big challenge to construct a microfluidic platform incorporating extracellular matrix (ECM) structures and highly controlled 3D gradients of soluble factors to study the regeneration of injured neurons. In this work, we developed a microfluidic device which can provide multiple adjustable gradients in a 3D ECM to investigate the regeneration of injured central nervous system (CNS) neurons in response to natural small molecules.

Real-Time Intracellular Measurements of ROS and RNS in Living Cells with Single Core-Shell Nanowire Electrodes.

Nanoelectrodes allow precise and quantitative measurements of important biological processes at the single living-cell level in real time. Cylindrical nanowire electrodes (NWEs) required for intracellular measurements create a great challenge for achieving excellent electrochemical and mechanical performances. Herein, we present a facile and robust solution to this problem based on a unique SiC-core-shell design to produce cylindrical NWEs with superior mechanical toughness provided by the SiC nano-core and an excellent electrochemical performance provided by the ultrathin carbon shell that can be used as such or platinized.