Neurofilament Light Chain under the Lens of Structural Mass Spectrometry.

Neurofilament light chain (NfL) is an early nonspecific biomarker in neurodegenerative diseases and traumatic brain injury, indicating axonal damage. This work describes the detailed structural characterization of a selected primary calibrator with the potential to be used in future reference measurement procedure (RMP) development for the accurate quantification of NfL. As a part of the described workflow, the sequence, higher-order structure as well as solvent accessibility, and hydrogen-bonding profile were assessed under three different conditions in KPBS, artificial cerebrospinal fluid, and artificial cerebrospinal fluid in the presence of human serum albumin.

A Strategy for Quantitative Imaging of Lanthanide Tags in A549 Cells Using the Ratio of Internal Standard Elements.

One remaining handicap for spatially resolved elemental quantification in biological samples is the lack of a suitable internal standard (IS) that can be reliably measured across both calibration standards and samples. In this work, multielement quantitative intracellular imaging of cells tagged with lanthanide nanoparticles containing key lanthanides, e.g.

Photosubstitution and photoreduction of a diazido platinum(IV) anticancer complex.

The hyphenation of HPLC with its high separation ability and ICP-MS with its excellent sensitivity, allows the analysis of Pt drugs in biological samples at the low nanomolar concentration levels. On the other hand, LC-MS provides molecular structural confirmation for each species. Using a combination of these methods, we have investigated the speciation of the photoactive anticancer complex diazido Pt(IV) complex , , -[Pt(N)(OH)(py)] (FM-190) in aqueous solution and biofluids at single-digit nanomolar concentrations before and after irradiation.

Comparing novel small-angle x-ray scattering approaches for absolute size and number concentration measurements of spherical SiOparticles to established methods.

Biomedical analytical applications, as well as the industrial production of high-quality nano- and sub-micrometre particles, require accurate methods to quantify the absolute number concentration of particles. In this context, small-angle x-ray scattering (SAXS) is a powerful tool to determine the particle size and concentration traceable to the Système international d'unités (SI). Therefore, absolute measurements of the scattering cross-section must be performed, which require precise knowledge of all experimental parameters, such as the electron density of solvent and particles, whereas the latter is often unknown.