Modulus characterization of cells with submicron colloidal probes by atomic force microscope

Abstract

Colloidal probes have been increasingly demanded for the characterization of cellular modulus in atomic force microscope because of their well-defined geometry and large contact area with cell. In this work, submicron colloidal probes are prepared by scanning electron microscope/focused ion beam and compared with sharp tip and micron colloidal probe, in conjunction with loading velocity and indentation depth on the apparent elastic modulus. NIM and cartilage cells are used as specimens. The results show that modulus value measured by sharp tip changes significantly with loading velocity while remains almost stable by colloidal probes. Also, submicron colloidal probe is superior in characterizing the modulus with increasing indentation depth, which could help reveal the mechanical details of cellular membrane and the modulus of the whole cell. To test the submicron colloidal probe further, the modulus distribution map of cell is scanned with submicron colloidal probe of 50 nm radius during small and large indentation depths with high spatial resolution. The outcome of this work will provide the effective submicron colloidal probe according to the effect of loading velocity and indentation depth, characterizing the mechanical properties of the cells.

Supramolecular Combination Chemotherapy: Cucurbit[8]uril Complex Enhanced Platinum Drug Infiltration and Modified Nanomechanical Property of Colorectal Cancer Cells

“…By observing the cell surface morphology and three-dimensional structure, quantitative parameters (cell surface area, thickness, width, and volume) are obtained. Some studies have shown that AFM can be used for cancer detection and drug identification. − Considering the clinical treatment of combination chemotherapy, we chose CB[8] with a larger cavity of 367 Å 3 to deliver materials. In this work, we tried to expand the research on the supramolecular approach by using two CB[8] - encapsulated chemotherapeutic drugs (lobaplatin, LP; eptaplatin, EP), which formed the LP + EP@CB[8] (CLE) complex and controlled the release of drugs through a colorectal tumor cell special biomarker.…”

Studies of probe tip materials by atomic force microscopy: a review

“…A colloidal probe [ 12 – 13 ] consists of colloidal particles attached to an AFM cantilever to measure the interaction force between the particle and the surface. A new colloidal AFM probe was proposed by Daboss et al [ 14 ].…”