Compact Quantum Cascade Laser-Based Noninvasive Glucose Sensor Upgraded with Direct Comb Data-Mining.

Mid-infrared spectral analysis has long been recognized as the most accurate noninvasive blood glucose measurement method, yet no practical compact mid-infrared blood glucose sensor has ever passed the accuracy benchmark set by the USA Food and Drug Administration (FDA): to substitute for the finger-pricking glucometers in the market, a new sensor must first show that 95% of their glucose measurements have errors below 15% of these glucometers. Although recent innovative exploitations of the well-established Fourier-transform infrared (FTIR) spectroscopy have reached such FDA accuracy benchmarks, an FTIR spectrometer is too bulky. The advancements of quantum cascade lasers (QCLs) can lead to FTIR spectrometers of reduced size, but compact QCL-based noninvasive blood glucose sensors are not yet available.

Serum protein albumin and chromium: Mechanistic insights into the interaction between ions, nanoparticles, and protein.

The interaction of human proteins and metal species, both ions and nanoparticles, is poorly understood despite their growing importance. These materials are the by-products of corrosion processes and are of relevance for food and drug manufacturing, nanomedicine, and biomedical implant corrosion. Here, we study the interaction of Cr(III) ions and chromium oxide nanoparticles with bovine serum albumin in physiological conditions.

Manipulating LiS/LiS mixed discharge products of all-solid-state lithium sulfur batteries for improved cycle life.

All-solid-state lithium-sulfur batteries offer a compelling opportunity for next-generation energy storage, due to their high theoretical energy density, low cost, and improved safety. However, their widespread adoption is hindered by an inadequate understanding of their discharge products. Using X-ray absorption spectroscopy and time-of-flight secondary ion mass spectrometry, we reveal that the discharge product of all-solid-state lithium-sulfur batteries is not solely composed of LiS, but rather consists of a mixture of LiS and LiS.

Time-of-flight secondary ion mass spectrometry analyses of vancomycin.

As an antibiotic that prevents and treats infections caused by Gram-positive bacteria such as Staphylococcus aureus, vancomycin incorporated in a biodegradable polymer poly(lactide-co-glycolide) provides opportunities to construct controlled-release drug delivery systems. Developments associated with this promising system have been largely concentrated on areas of drug delivery kinetics and biodegradability. In order to provide surface analytical approaches to this important system, the authors demonstrate applicability of time-of-flight secondary ion mass spectrometry (TOF-SIMS) in three-dimensional molecular imaging for a model system consisting of alternating layers of ploy(lactide-co-glycolide) and vancomycin.

Scaffold composed of porous vancomycin-loaded poly(lactide-co-glycolide) microspheres: A controlled-release drug delivery system with shape-memory effect.

Loading antibiotics in a biodegradable polymer matrix is an excellent way to control its release kinetics, which eliminates side effects caused by conventional administrations of the drug. This approach is especially beneficial for bone regeneration when using a scaffold made of a biodegradable polymer loaded with drug agents capable of controllable releases. In this case, the scaffold serves as a mechanical support to tissue formation and the drug agents may provide biomolecules to assist the tissue formation and/or provide antibiotics to prevent tissues from infections.

Depth profiling cross-linked poly(methyl methacrylate) films: a time-of-flight secondary ion mass spectrometry approach.

Rationale: In order to determine the degree of cross-linking on the surface and its variations in a nanometer-scale depth of organic materials, we developed an approach based on time-of-flight secondary ion mass spectrometry (TOF-SIMS), which provides rich chemical information in the form of fragment ions. TOF-SIMS is extremely surface-sensitive and capable of depth profiling with the use of a sputter ion beam to remove controllable amounts of substance.

Methods: Poly(methyl methacrylate) (PMMA) films spin-coated on a Si substrate were cross-linked using a recently developed, surface sensitive, hyperthermal hydrogen projectile bombardment technique.

Cross-Linking the Surface of Cured Polydimethylsiloxane via Hyperthemal Hydrogen Projectile Bombardment.

Cross-linking of polydimethylsiloxane (PDMS) is increasingly important with recent focus on its top surface stiffness. In this paper, we demonstrate that hyperthermal hydrogen projectile bombardment, a surface sensitive cross-linking technology, is superior in enhancing the mechanical properties of a cured PDMS surface without significantly degrading its hydrophobicity. Both water contact angle measurements and time-of-flight secondary ion mass spectrometry are used to investigate the variations in surface chemistry and structure upon cross-linking.

Revealing different bonding modes of self-assembled octadecylphosphonic acid monolayers on oxides by time-of-flight secondary ion mass spectrometry: silicon vs aluminum.

Condensed octadecylphosphonic acid (OPA) dimers, i.e., two OPA molecules combined with the loss of a water molecule, were detected by time-of-flight secondary ion mass spectrometry (TOF-SIMS) on OPA self-assembled monolayers (SAMs) that are only weakly bonded on the native oxide layer of a silicon wafer.

Delivering octadecylphosphonic acid self-assembled monolayers on a Si wafer and other oxide surfaces.

We describe a simple experimental approach for delivering self-assembled monolayers (SAMs) of octadecylphosphonic acid (OPA) on many oxide surfaces using a nonpolar medium with a dielectric constant around 4 (e.g., trichloroethylene).