Real‐time Amyloid Aggregation Monitoring with a Photonic Crystal‐based Approach

Abstract

We propose the application of a new label‐free optical technique based on photonic nanostructures to real‐time monitor the amyloid‐beta 1‐42 (Aβ(1‐42)) fibrillization, including the early stages of the aggregation process, which are related to the onset of the Alzheimer’s Disease (AD). The aggregation of Aβ peptides into amyloid fibrils has commonly been associated with neuronal death, which culminates in the clinical features of the incurable degenerative AD. Recent studies revealed that cell toxicity is determined by the formation of soluble oligomeric forms of Aβ peptides in the early stages of aggregation. At this phase, classical amyloid detection techniques lack in sensitivity. Upon a chemical passivation of the sensing surface by means of polyethylene glycol, the proposed approach allows an accurate, real‐time monitoring of the refractive index variation of the solution, wherein Aβ(1‐42) peptides are aggregating. This measurement is directly related to the aggregation state of the peptide throughout oligomerization and subsequent fibrillization. Our findings open new perspectives in the understanding of the dynamics of amyloid formation, and validate this approach as a new and powerful method to screen aggregation at early stages.

Synchrotron-Infrared Microscopy Analysis of Amyloid Fibrils Irradiated by Mid-Infrared Free-Electron Laser

“…This study has revealed that structural changes could be observed after FEL irradiation, but planned future work will focus on observing the changes in real time during FEL irradiation by connecting the IR microscope to the FEL beamline. Such a strategy is likely to allow an investigation of the structural machinery and folding kinetics of amyloid fibrils on a microscopic level, as described in a recent paper [30]. By using the FEL irradiation system combined with the IR microscopy, it can be expected that the disaggregation mechanism of amyloid fibrils will be investigated.…”

In Situ Measurement and Monitoring of Diphenyl Disulfide in Ethanol Solution by SERS

“…Real-time monitoring technology can be applied to effectively detect pertinent changes in parameters during chemical processes [4]. In recent years, the widespread use of real-time monitoring technology has included spectroscopic methods [5], chromatography, and chromatography coupled with spectral detection [6][7].…”

Bloch surface waves based platform for integrated optics

“…Furthermore, platform provides the possibility to work with both polarizations and with any wavelength by properly choosing the refractive index and thickness of the layers constituting the multilayer. Taking the advantage of field confinement, the platform has also an application in the sensing domain [2].…”