title: Toward the realization of reproducible Atomic Force Microscopy measurements of elastic modulus in biological samples.
abstract: The validation of the AFM method for elastic modulus E measurement in soft materials (E <5 MPa) is still missing. The interest of measurements in materials with E <5 MPa is mainly biological, including soft tissues and single cells. For the diagnosis of malignant human tumors, a change in cell elasticity, within tissues, has recently been recognized as a marker of metastatic potential. To measure a cell elasticity difference, reproducible E measurements in biological samples are needed. In this work a robust method for a metrological validation of E measurements in the range 500-5000 kPa was developed, based on the realization of thick E standard samples and on the study of the interactions between the measurement process and the sample at micro- and nano-scale. E measurement reproducibility limit of 4% has been reached. This allows designing a very sensitive and reproducible measurement of E in biological samples representing thus a powerful diagnostic tool for cancer detection.
authors: Istituto Nazionale di Ricerca Metrologica INRIM, Torino, Italy. Electronic address: a.demichelis@inrim.it.
authors: A
authors: A
authors: Demichelis
authors: Istituto Nazionale di Ricerca Metrologica INRIM, Torino, Italy.
authors: C
authors: C
authors: Divieto
authors: Istituto Nazionale di Ricerca Metrologica INRIM, Torino, Italy.
authors: L
authors: L
authors: Mortati
authors: Istituto Nazionale di Ricerca Metrologica INRIM, Torino, Italy.
authors: S
authors: S
authors: Pavarelli
authors: Istituto Nazionale di Ricerca Metrologica INRIM, Torino, Italy; Dipartimento di Scienza dei Materiali e Ingegneria Chimica, Politecnico di Torino, Italy.
authors: G
authors: G
authors: Sassi
authors: Istituto Nazionale di Ricerca Metrologica INRIM, Torino, Italy.
authors: M P
authors: MP
authors: Sassi
mesh_terms: D004129:Dimethylpolysiloxanes; D055119:Elastic Modulus / Q000502:physiology*; D004548:Elasticity / Q000502:physiology; D006801:Humans; D018625:Microscopy, Atomic Force / Q000379:methods*; D009369:Neoplasms / Q000175:diagnosis / Q000503:physiopathology; D015203:Reproducibility of Results
chemical_list: D004129:Dimethylpolysiloxanes; C013830:baysilon
keywords: AFM; Cell biology; Elastic modulus; Metrology; Sylgard; Tumor cell; Tumor tissues