A Method for Analyzing AFM Force Mapping Data Obtained from Soft Tissue Cryosections

• Type of Material: Article
• Authors: Cydney Wong, Emory University; Nina Sara Fraticelli Guzmán, Georgia Institute of Technology; A. Thomas Read, Emory University; Adam Hedberg-Buenz, University of Iowa, Iowa City; Michael G. Anderson, University of Iowa, Iowa City; Andrew Feola, Emory University; Todd Sulchek, Emory University; Ross Ethier, Emory University
• Language: English
• Date: 2023-11-13
• Publisher: NIH
• Publication Version: Preprint (Prior to Peer Review)
• Copyright Statement: The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): https://doi.org/10.1101/2023.11.08.566263
• Title of Journal or Parent Work: bioRxiv
• Start Page: 566263
• Grant/Funding Information: This work was supported by the NIH (Diversity Supplement EY031710-01S1 [CAW], R01 EY031710-01S1 [CRE], T32 Training Grant GM145735 [CAW], R21 EY031598 [MGA], R01 EY030871 [AJF], P30EY006360 [AJF], Training Grant T32 EY007092 [NSFG]), the Georgia Research Alliance (CRE), NSF CBET 2225476 [TAS], the Alfred P. Sloan Foundation G-2019-11435 [NSFG] and the Department of Veterans Affairs Rehab R&D Service Career Development Awards to AJF (CDA-2; RX002342).
• Keywords: Atomic force microscopy; tissue engineering; biomechanics
• Research Categories: Engineering, Biomedical

Abstract

Atomic force microscopy (AFM) is a valuable tool for assessing mechanical properties of biological samples, but interpretations of measurements on whole tissues can be difficult due to the tissue’s highly heterogeneous nature. To overcome such difficulties and obtain more robust estimates of tissue mechanical properties, we describe an AFM force mapping and data analysis pipeline to characterize the mechanical properties of cryosectioned soft tissues. We assessed this approach on mouse optic nerve head and rat trabecular meshwork, cornea, and sclera. Our data show that the use of repeated measurements, outlier exclusion, and log-normal data transformation increases confidence in AFM mechanical measurements, and we propose that this methodology can be broadly applied to measuring soft tissue properties from cryosections.