Correlative nanoscopy: A multimodal approach to molecular resolution

Abstract

Atomic force microscopy (AFM) is a nano-mechanical tool uniquely suited for biological studies at the molecular scale. AFM operation is based on mechanical interaction between the tip and the sample, a mechanism of contrast capable of measuring different information, including surface topography, mechanical, and electrical properties. However, the lack of specificity highlights the need to integrate AFM data with other techniques providing compositional hints. In particular, optical microscopes based on fluorescence as a mechanism of contrast can access the local distribution of specific molecular species. The coupling between AFM and super-resolved fluorescence microscopy solves the resolution mismatch between AFM and conventional fluorescence optical microscopy. Recent advances showed that also the inherently label-free imaging capabilities of the AFM are fundamental to complement the fluorescence images. In this review, we have presented a brief historical view on correlative microscopy, and, finally, we have summarized the progress of correlative AFM-super-resolution microscopy in biological research.

AFM‐TEM correlation microscopy and its application to lipid nanoparticles

“…Usually, the specimen has some features to facilitate navigation and selection of the region of interest (ROI). Some examples of correlation microscopy include combinations of optical imaging techniques with atomic‐force microscopy (AFM), (Jadavi et al, 2021) scanning electron microscopy (SEM), (Casares‐Arias et al, 2021; Katsen‐Globa et al, 2016; Liv et al, 2013) or with cryo‐EM, including cryo‐tomography (Bokstad & Medalia, 2014; Sartori et al, 2007; Sartori‐Rupp et al, 2019; Schorb et al, 2017). The growing popularity of correlation microscopy fuels the development of combined devices, for example, AFM‐Raman systems (Abramczyk et al, 2019; Surtchev et al, 2016), which allows one to access a particular ROI with different analytical methods without the sample transfer between the microscopes.…”

“…Usually, the specimen has some features to facilitate navigation and selection of the region of interest (ROI). Some examples of correlation microscopy include combinations of optical imaging techniques with atomic-force microscopy (AFM), (Jadavi et al, 2021) scanning electron microscopy (SEM), (Casares-Arias et al, 2021;…”

Fluorescence labeling methods influence the aggregation process of α-syn in vitro differently

“…1 In particular, correlative microscopy is based on the coupling of techniques that can provide local multifunctional characterization of the sample. 2,3 The most widespread correlative microscopy applications are related to the coupling of electron and optical microscopy. [4][5][6][7] However, in recent years, the integration between atomic force microscopy (AFM) and super-resolution (SR) fluorescence microscopy has been proposed as a primary method in the study of bio-systems.…”

“…[4][5][6][7] However, in recent years, the integration between atomic force microscopy (AFM) and super-resolution (SR) fluorescence microscopy has been proposed as a primary method in the study of bio-systems. 3,[8][9][10][11][12] The substantial advantage of this approach is the inherent capability of both techniques to work in a liquid environment, enabling simultaneous investigation of living systems, such as cells, or dynamic molecular processes, in a physiological-like environment, and at molecular-scale resolution.…”

Comparison of different correlative AFM-SEM workflows on calcite moonmilk

“…The first and most known example of correlative microscopy is the CLEM -Correlative Light to Electron Microscopy -where the high-resolution imaging of the electron microscope is correlated with a fluorescence optical analysis, thus granting the possibility to highlight information regarding the internal functions of cells and tissues [2]. However, not only light and electron microscopies can be combined, but by adopting specific protocols, a great number of combinations with different characterizing techniques, such as Raman or Atomic Force Microscope (AFM) can be done [3,4]. All the available configurations make the correlative microscopy a very powerful tool, capable to improve the knowledge of complex phenomena that can't be achieved by the standalone microscopies, while, at 1265 (2022) 012011 IOP Publishing doi:10.1088/1757-899X/1265/1/012011 2 the same time, it avoids dispersion of data due to different sample preparations and treatments [1].…”