Frequency dependent viscoelastic properties of porcine brain tissue

Abstract

Where a licence is displayed above, please note the terms and conditions of the licence govern your use of this document. When citing, please reference the published version. Take down policy While the University of Birmingham exercises care and attention in making items available there are rare occasions when an item has been uploaded in error or has been deemed to be commercially or otherwise sensitive.

Dynamic mechanical characterization and viscoelastic modeling of bovine brain tissue

“…The mean dynamic viscoelastic properties of bovine brain tissue are frequency-dependency and the storage modulus was constantly higher than the loss modulus for every frequency. In comparison to a study [40] on the compressive viscoelastic properties of porcine brain tissue where the mean storage and loss moduli were 8.09 kPa and 4.85 kPa, respectively, the bovine brain in this study had higher dynamic moduli at comparable frequencies. In addition, animal brain tissues were tested using dynamic shear [61] and tensile methods [45] to analyze the oscillatory characterization.…”

“…The viscoelastic properties of brain tissue specimens were characterized using a Bose ElectroForce 3200 (Bose Corporation, ElectroForce Systems Group, Minnesota, USA) testing machine operated with WinTest Dynamic Mechanical Analysis software (Bose Corporation, ElectroForce Systems Group, Minnesota, USA). Other biological and synthetic materials were previously tested using this approach [40][41] [42]. The Bose testing machine was equipped with a 225 N load cell with a resolution of 0.002 N and a high accuracy displacement sensor with a resolution of 0.001 mm.…”

“…The range of frequencies is relevant to the strain rates comparable with previous studies on bovine [31], porcine [26] and human brains [32] and also to which the brain might be exposed during physiological and injury conditions [7]. Prior to the data collection procedure, a preload of 10 mN was initially applied to specimens to ensure a zero configuration and a preconditioning cycle of 1 Hz with 0.05 mm amplitude was then performed to stabilize the samples [45][46] [40]. All tests were performed at room temperature with the sampling rate of acquisition at 5 kHz for the highest frequency tested.…”

Towards organoid culture without Matrigel

“…Synthetic hydrogels also have readily tunable viscoelastic properties, such as loss modulus and characteristic relaxation time. Many relevant tissues are viscoelastic, with brain tissue in particular not only having a strong dissipative component (i.e., high loss modulus) in its response to stress 137 but also having slight differences in viscoelastic properties between white matter and gray matter 138 . The viscoelastic properties of a material affect matrix remodeling, cell spreading, migration, differentiation, and consequently, organoid fate 139 – 141 .…”

Investigation of the Compressive Viscoelastic Properties of Brain Tissue Under Time and Frequency Dependent Loading Conditions

“… 27 On arrival in the laboratory, the brains were stored at – 40 °C wrapped in tissue paper soaked in Ringer’ solution (Oxoid Ltd, Basingstoke, UK) following the standard procedure. 28 , 52 Prior to the mechanical tests, brain samples were thawed in Ringer’ solution for 12 h before dissection. The freeze-thaw process has not been found to adversely affect the mechanical properties of biological tissue.…”