Identification of nanoparticles and nanosystems in biological matrices with scanning probe microscopy

Abstract

Identification of nanoparticles and nanosystems into cells and biological matrices is a hot research topic in nanobiotechnologies. Because of their capability to map physical properties (mechanical, electric, magnetic, chemical, or optical), several scanning probe microscopy based techniques have been proposed for the subsurface detection of nanomaterials in biological systems. In particular, atomic force microscopy (AFM) can be used to reveal stiff nanoparticles in cells and other soft biomaterials by probing the sample mechanical properties through the acquisition of local indentation curves or through the combination of ultrasound-based methods, like contact resonance AFM (CR-AFM) or scanning near field ultrasound holography. Magnetic force microscopy can detect magnetic nanoparticles and other magnetic (bio)materials in nonmagnetic biological samples, while electric force microscopy, conductive AFM, and Kelvin probe force microscopy can reveal buried nanomaterials on the basis of the differences between their electric properties and those of the surrounding matrices. Finally, scanning near field optical microscopy and tip-enhanced Raman spectroscopy can visualize buried nanostructures on the basis of their optical and chemical properties. Despite at a still early stage, these methods are promising for detection of nanomaterials in biological systems as they could be truly noninvasive, would not require destructive and time-consuming specific sample preparation, could be performed in vitro, on alive samples and in water or physiological environment, and by continuously imaging the same sample could be used to dynamically monitor the diffusion paths and interaction mechanisms of nanomaterials into cells and biological systems. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

3D-Printed Submicron Patterns Reveal the Interrelation between Cell Adhesion, Cell Mechanics, and Osteogenesis

“…Therefore, the elastic moduli of the living cells interacting with the patterned (S2, S3, L2, and L3) and control surfaces were analyzed by acquiring AFM mechanical maps of the cells after 1 day of culture (Figure ). Exploiting the capability of AFM-based stiffness measurements to perform subsurface imaging of soft biological samples up to a depth of 900 nm , also allows for a more detailed analysis of the organization of cortical actin, especially in the perinuclear region.…”

Magnetic force microscopy characterization of cobalt nanoparticles: A preliminary study

“…Really, different techniques implementing MFM allowed to study different properties of different nanosystems based on magnetic NPs, e.g. : to detect the presence of magnetic NPs in polymers or biological matrices [18][19][20][21][22][23]; to study field-related magnetic phenomena in iron-oxide NPs [24,25]; to quantitatively determine magnetic moment and saturation magnetization of iron oxide NPs [26][27][28]; to investigate superparamagnetic NPs [24,29,30]. Also, MFM was used to investigate Co [31] and CoPt [32] nanostructures and Co nanoclusters [33].…”

Enhance the detection of surface micro/nanostructures by SPPs generated from silver film covered hemi-microsphere

“…Surface micro/nanostructures detection is of great significance in broad research fields, such as biomedical [1,2], environmental monitoring [3], micro-nano optics [4], and so on. The common surface micro/ nanostructures detection methods contain laser interferometry [5], scanning probe techniques [6], scanning electron microscopy [7,8], scanning near-field microscopy [9], and Raman spectroscopy [10]. Achieving fast, high-resolution, and non-destructive testing in a large size range is a vital development direction of surface micro/nanostructures detection.…”