Publications by authors named "Stylianos-Vasileios Kontomaris"

When testing biological samples with atomic force microscopy (AFM) nanoindentation using pyramidal indenters, Sneddon's equation is commonly used for data processing, approximating the indenter as a perfect cone. While more accurate models treat the AFM tip as a blunted cone or pyramid, these are complex and lack a direct relationship between applied force and indentation depth, complicating data analysis. This paper proposes a new equation derived from simple mathematical processes and physics-based criteria.

View Article and Find Full Text PDF

Atomic force microscopy (AFM) is a powerful tool for characterizing biological materials at the nanoscale utilizing the AFM nanoindentation method. When testing biological materials, spherical indenters are typically employed to reduce the possibility of damaging the sample. The accuracy of determining Young's modulus depends, among other factors, on the calibration of the indenter, i.

View Article and Find Full Text PDF

Elastin is an extracellular matrix protein, providing elasticity to the organs, such as skin, blood vessels, lungs and elastic ligaments, presenting self-assembling ability to form elastic fibers. The elastin protein, as a component of elastin fibers, is one of the major proteins found in connective tissue and is responsible for the elasticity of tissues. It provides resilience to the human body, assembled as a continuous mesh of fibers that require to be deformed repetitively and reversibly.

View Article and Find Full Text PDF

Atomic Force Microscopy (AFM) is a powerful tool enabling the mechanical characterization of biological materials at the nanoscale. Since biological materials are highly heterogeneous, their mechanical characterization is still considered to be a challenging procedure. In this paper, a new approach that leads to a 3-dimensional (3D) nanomechanical characterization is presented based on the average Young's modulus and the AFM indentation method.

View Article and Find Full Text PDF

Measuring the mechanical properties (i.e., elasticity in terms of Young's modulus) of biological samples using Atomic Force Microscopy (AFM) indentation at the nanoscale has opened new horizons in studying and detecting various pathological conditions at early stages, including cancer and osteoarthritis.

View Article and Find Full Text PDF

Atomic Force Microscopy nanoindentation method is a powerful technique that can be used for the nano-mechanical characterization of bio-samples. Significant scientific efforts have been performed during the last two decades to accurately determine the Young's modulus of collagen fibrils at the nanoscale, as it has been proven that mechanical alterations of collagen are related to various pathological conditions. Different contact mechanics models have been proposed for processing the force-indentation data based on assumptions regarding the shape of the indenter and collagen fibrils and on the elastic or elastic-plastic contact assumption.

View Article and Find Full Text PDF

Atomic force microscopy (AFM) is an easy-to-use, powerful, high-resolution microscope that allows the user to image any surface and under any aqueous condition. AFM has been used in the investigation of the structural and mechanical properties of a wide range of biological matters including biomolecules, biomaterials, cells, and tissues. It provides the capacity to acquire high-resolution images of biosamples at the nanoscale and allows at readily carrying out mechanical characterization.

View Article and Find Full Text PDF