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This content will become publicly available on June 1, 2026

Title: Correlation of collagen damage and failure mechanics in porcine pia-arachnoid complex
Mild traumatic brain injury (mTBI) accounts for approximately 75% of all TBI cases, and the mechanisms are still poorly understood, in part due to limitations of current diagnostic tools. Yet, there is a critical need to detect the presence of mTBI to mitigate risk of further injury. In this study, we explore the potential of collagen hybridizing peptides (CHPs), which selectively bind to damaged collagen, to detect damage in the pia-arachnoid complex (PAC), a major load-transferring interface during head trauma. To generate damage, porcine PAC samples underwent peel tests. Peak force to failure and CHP fluorescence were measured in three regions of the brain at multiple post-mortem times. The peak force of PAC failure was region-specific, with increasing failure forces moving anterior to posterior (frontal: 20.91 ± 38.77 mN; parietal: 64.72 ± 33.31 mN; occipital: 86.68 ± 43.46 mN) and significantly different between frontal and occipital regions (p = 0.034). CHP fluorescence was significantly different between control and peeled PAC samples in mean pixel intensity (MPI; p = 0.031), median pixel intensity (MedPI; p = 0.009), and percent pixels above a defined threshold (PP; p = 0.014). Each of these CHP fluorescence metrics were significantly and positively correlated with peak force at failure (MPI: p = 0.049; MedPI: p = 0.026; PP: p = 0.002). These data suggest CHP is a viable solution to detecting the presence and severity of damage at the brain-skull interface, and may be a useful tool for quantifying damage in vivo.  more » « less
Award ID(s):
2140373
PAR ID:
10611138
Author(s) / Creator(s):
;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Journal of Biomechanics
Volume:
187
Issue:
C
ISSN:
0021-9290
Page Range / eLocation ID:
112745
Subject(s) / Keyword(s):
Pia-arachnoid complex Traumatic brain injury Brain-skull interface Collagen damage Collagen hybridizing peptides
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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