In vivo liquid biopsy for glioblastoma malignancy by the AFM and LSPR based sensing of exosomal CD44 and CD133 in a mouse model.

Glioblastoma (GBM) is the fatal brain tumor in which secreted lactate enhances the expression of cluster of differentiation 44 (CD44) and the release of exosomes, cell-derived nanovesicles (30-200 nm), and therefore promotes tumor malignant progression. This study found that lactate-driven upregulated CD44 in malignant Glioblastoma cells (GMs) enhanced the release of CD44-enriched exosomes which increased GMs' migration and endothelial cells' tube formation, and CD44 in the secreted exosomes was sensitively detected by "capture and sensing" Titanium Nitride (TiN) - Nanoholes (NH) - discs immunocapture (TIC) - atomic force microscopy (AFM) and ultrasensitive TiN-NH-localized surface plasmon resonance (LSPR) biosensors. The limit of detection for exosomal CD44 with TIC-AFM- and TiN-NH-LSPR-biosensors was 5.

Label-free surface plasmon resonance biosensing with titanium nitride thin film.

In this report, titanium nitride thin film synthesized with reactive magneto-sputtering technique is proposed as an alternative surface plasmon resonance sensing material. The physical and chemical natures were initially studied by atomic force microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. In virtue of white-light common-path sensing system, the wavelength modulated TiN films achieved tunable evanescent plasmonic field from 573 nm to 627 nm.

Encapsulating Co P@C Core-Shell Nanoparticles in a Porous Carbon Sandwich as Dual-Doped Electrocatalyst for Hydrogen Evolution.

A highly efficient and pH-universal hydrogen evolution reaction (HER) electrocatalyst with a sandwich-architecture constructed using zero-dimensional N- and P-dual-doped core-shell Co P@C nanoparticles embedded into a 3 D porous carbon sandwich (Co P@N,P-C/CG) was synthesized through a facile two-step hydrothermal carbonization and pyrolysis method. The interfacial electron transfer rate and the number of active sites increased owing to the synergistic effect between the N,P-dual-doped Co P@C core-shell and sandwich-nanostructured substrates. The presence of a high surface area and large pore sizes improved the mass-transfer dynamics.

A redox-controlled electrolyte for plasmonic enhanced dye-sensitized solar cells.

Plasmonic enhanced dye-sensitized solar cells (DSSCs) with metallic nanostructures suffer from corrosion problems, especially with the presence of the iodine/triiodide redox couple in the electrolyte. Herein, we introduce an alternative approach by compensating the corrosion with a modified liquid electrolyte. In contrast to the existing method of surface preservation for plasmonic nanostructures, the redox-controlled electrolyte (RCE) contains iodoaurate intermediates, i.

Initial Reduction of CO on Pd-, Ru-, and Cu-Doped CeO(111) Surfaces: Effects of Surface Modification on Catalytic Activity and Selectivity.

Surface modification by metal doping is an effective treatment technique for improving surface properties for CO reduction. Herein, the effects of doped Pd, Ru, and Cu on the adsorption, activation, and reduction selectivity of CO on CeO(111) were investigated by periodic density functional theory. The doped metals distorted the configuration of a perfect CeO(111) by weakening the adjacent Ce-O bond strength, and Pd doping was beneficial for generating a highly active O vacancy.

Direct detection of two different tumor-derived extracellular vesicles by SAM-AuNIs LSPR biosensor.

Extracellular vesicles (EVs) are abundant in various biological fluids including blood, saliva, urine, as well as extracellular milieu. Accumulating evidence has indicated that EVs, which contain functional proteins and small RNAs, facilitate intercellular communication between neighbouring cells, and are critical to maintain various physiological processes. In contrast, EV-derived toxic signals can spread out over the tissues adjacent to the injured area in certain diseases, including brain tumors and neurodegenerative disorders.

Label-Free LSPR Detection of Trace Lead(II) Ions in Drinking Water by Synthetic Poly(mPD-co-ASA) Nanoparticles on Gold Nanoislands.

Using self-assembly gold nanoislands (SAM-AuNIs) functionalized by poly(m-phenylenediamine-co-aniline-2-sulfonic acid) (poly(mPD-co-ASA)) copolymer nanoparticles as specific receptors, a highly sensitive localized surface plasmon resonance (LSPR) optochemical sensor is demonstrated for detection of trace lead cation (Pb(II)) in drinking water. The copolymer receptor is optimized in three aspects: (1) mole ratio of mPD:ASA monomers, (2) size of copolymer nanoparticles, and (3) surface density of the copolymer. It is shown that the 95:5 (mPD:ASA mole ratio) copolymer with size less than 100 nm exhibits the best Pb(II)-sensing performance, and the 200 times diluted standard copolymer solution contributes to the most effective functionalization protocol.

Methanol Oxidation on Pt3Sn(111) for Direct Methanol Fuel Cells: Methanol Decomposition.

PtSn alloy, which is a potential material for use in direct methanol fuel cells, can efficiently promote methanol oxidation and alleviate the CO poisoning problem. Herein, methanol decomposition on Pt3Sn(111) was systematically investigated using periodic density functional theory and microkinetic modeling. The geometries and energies of all of the involved species were analyzed, and the decomposition network was mapped out to elaborate the reaction mechanisms.

Label-free detection of 3-nitro-l-tyrosine with nickel-doped graphene localized surface plasmon resonance biosensor.

3-nitro-l-tyrosine (3-NT) is believed to be a biomarker of neurodegenerative diseases and metal doped graphene possess exceptionally high binding energy of 3-NT with metal-nitro chemisorption. Here we report a novel label-free detection scheme of 3-NT via nickel-doped graphene (NDG) as the functionalized receptor on our phase detecting localized surface plasmon resonance (LSPR) biosensor. When compared with reported 3-NT immunoassay with enzyme-linked immunosorbent assay (ELISA), our NDG-LSPR platform offers two advantages i.

Differential phase-detecting localized surface plasmon resonance sensor with self-assembly gold nano-islands.

Self-assembly (SAM) gold nano-islands are fabricated by two-step thin-film deposition-annealing method. Despite random distribution of the SAM, the p-polarized light after total internal reflection shows significant phase transition at the extinction wavelengths upon refractive index variation due to localized surface plasmon resonance (LSPR) effect. It resembles the sharp phase transition observed in conventional surface plasmon resonance (SPR) biosensors, so that the bulk sensitivity of the SAM-LSPR sensor is improved via the phase interrogation method.

Common-path spectral interferometry with temporal carrier for highly sensitive surface plasmon resonance sensing.

Incorporating the temporal carrier technique with common-path spectral interferometry, we have successfully demonstrated an advanced surface plasmon resonance (SPR) biosensing system which achieves refractive index resolution (RIR) up to 2 × 10(-8) refractive index unit (RIU) over a wide dynamic range of 3 × 10(-2) RIU. While this is accomplished by optimizing the SPR differential phase sensing conditions with just a layer of gold, we managed to address the spectral phase discontinuity with a novel spectral-temporal phase measurement scheme. As the new optical setup supersedes its Michelson counterpart in term of simplicity, we believe that it is a significant contribution for practical SPR sensing applications.

White-light spectral interferometry for surface plasmon resonance sensing applications.

A novel differential phase detecting surface plasmon resonance (SPR) sensor based on white-light spectral interferometry is presented. Our proposed scheme employs a white-light source for SPR excitation and measures the corresponding SPR phase change at the optimized coupling wavelength with fixed angle of incidence across the visible spectrum. Compared to existing laser based phase detecting schemes, this system offers optimal sensitivity and extended dynamic range of measurement without any compromise in phase detection resolution.

Differential spectral phase interferometry for wide dynamic range surface plasmon resonance biosensing.

We introduce a novel wide dynamic range phase-sensitive surface plasmon resonance (SPR) biosensor based on differential spectral interferometry. Superseding conventional spectroscopic approach where only the SPR dip is monitored, our system acquires the spectral phase information of the entire electromagnetic field that undergoes SPR transformation. Since the SPR-induced phase change is highly wavelength specific with fixed incident angle, ultra-high sensitivity achievable through phase-sensitive detection, as reported herein, is maintained continuously across the spectral domain in response to refractive index changes.