Fibrillogenesis of human β₂‐microglobulin in three‐dimensional silicon microstructures

Abstract

The authors describe the interaction of biological nanostructures formed by β(2) -microglobulin amyloid fibrils with three-dimensional silicon microstructures consisting in periodic arrays of vertical silicon walls (≈3 μm-thick) separated by 50 μm-deep air gaps (≈5 μm-wide). These structures are of great interest from a biological point of view since they well mimic the interstitial environment typical of amyloid deposition in vivo. Moreover, they behave as hybrid photonic crystals, potentially applicable as optical transducers for label-free detection of the kinetics of amyloid fibrils formation. Fluorescence and atomic force microscopy (AFM) show that a uniform distribution of amyloid fibrils is achieved when fibrillogenesis occurs directly on silicon. The high resolution AFM images also demonstrate that amyloid fibrils grown on silicon are characterized by the same fine structure typically ensured by fibrillogenesis in solution.

A New Cell-Selective Three-Dimensional Microincubator Based on Silicon Photonic Crystals

“…We have recently proposed the use of silicon devices based on a well-ordered material as a three-dimensional supporting matrix for biological nanostructures [22] and for optofluidic applications [23]. In this paper, a cell-selective silicon microincubator, that incorporates a vertical, high aspect-ratio (HAR) silicon photonic crystal (PhC) as core element, is successfully demonstrated for performing cell cultures in a 3-D microenvironment.…”

Low-Coherence Reflectometry for Refractive Index Measurements of Cells in Micro-Capillaries

“…The proposed approach is simple and the measurements could be potentially performed with an automatic sequence, at several positions of the capillary, in order to have average data on a sufficiently large number of cells. This non-invasive method, based on a low-power, infrared readout beam, for measuring the group refractive index of non-homogeneous biological samples could be applied also on micro-fluidic systems, integrating micro-channels with rectangular cross-sections, allowing RI measurements on highly scattering biological samples [38]. As micro-capillaries can also be used as flow-through devices, it would in principle also be possible to detect in real time the response of a group of cells to environmental changes induced in the capillary itself.…”

An Innovative Cell Microincubator for Drug Discovery Based on 3D Silicon Structures

“…Microstructures. Three-dimensional silicon microstructures (3D-SMSs) of this work were fabricated by means of electrochemical micromachining technology (ECM), which is detailed in [5,6,24]. 3D-SMSs, consisting of vertical ≈3 m-thick silicon walls periodically separated by 50 m-deep and ≈5 m-wide air gaps, were integrated within a circular region (surface area of 0.64 cm 2 ) of a silicon die with size 1.5 cm × 1.5 cm.…”