Elasticity of whole blood clots measured via Volume Controlled Cavity Expansion
Elasticity of whole blood clots measured via Volume Controlled Cavity Expansion
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通过体积控制腔扩张测量全血凝块的弹性
DOI：
10.1016/j.jmbbm.2023.105901
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发表时间：
2023
影响因子：
3.9
通讯作者：
Cohen, Tal
中科院分区：
文献类型：
--
作者：
Varner, Hannah;Sugerman, Gabriella P.;Rausch, Manuel K.;Cohen, Tal
测量和了解血凝块的机械特性可以深入了解疾病进展和潜在治疗的有效性。然而，一些限制阻碍了使用标准机械测试方法来测量软生物组织（如血凝块）的响应。这些组织可能难以安装，并且是不均匀的，形状不规则的，稀缺的，有价值的。为了弥补这一点，我们在这项工作中采用体积控制腔膨胀（VCCE），最近开发的一种技术，以测量软材料在其自然环境中的局部力学性能。通过高度控制注射针头尖端处的水气泡的体积膨胀，并同时测量阻力，我们获得了全血凝块机械响应的局部特征。将这些数据与预测理论模型进行比较，我们发现1项Ogden模型足以捕获我们实验中观察到的非线性弹性响应，并产生与文献中报道的值相当的剪切模量值。此外，我们发现在4° C下储存超过2天的牛全血显示出剪切模量从第2天的2.53±0.44 kPa（N= 13）到第3天的1.23±0.18 kPa（N= 14）的统计学显著变化。与先前报道的结果相反，我们的样品在0.22-21.1 s-1的应变速率范围内没有表现出粘弹性速率敏感性。通过调查现有的全血凝块数据进行比较，我们表明这种技术提供了高度可重复和可靠的结果，因此我们建议更广泛地采用VCCE作为更好地理解软生物材料力学的途径。
Measuring and understanding the mechanical properties of blood clots can provide insights into disease progression and the effectiveness of potential treatments. However, several limitations hinder the use of standard mechanical testing methods to measure the response of soft biological tissues, like blood clots. These tissues can be difficult to mount, and are inhomogeneous, irregular in shape, scarce, and valuable. To remedy this, we employ in this work Volume Controlled Cavity Expansion (VCCE), a technique that was recently developed, to measure local mechanical properties of soft materials in their natural environment. Through highly controlled volume expansion of a water bubble at the tip of an injection needle, paired with simultaneous measurement of the resisting pressure, we obtain a local signature of whole blood clot mechanical response. Comparing this data with predictive theoretical models, we find that a 1-term Ogden model is sufficient to capture the nonlinear elastic response observed in our experiments and produces shear modulus values that are comparable to values reported in the literature. Moreover, we find that bovine whole blood stored at 4° C for greater than 2 days exhibits a statistically significant shift in the shear modulus from 2.53±0.44 kPa on day 2 (N= 13) to 1.23±0.18 kPa on day 3 (N= 14). In contrast to previously reported results, our samples did not exhibit viscoelastic rate sensitivity within strain rates ranging from 0.22–21.1 s− 1. By surveying existing data on whole blood clots for comparison, we show that this technique provides highly repeatable and reliable results, hence we propose the more widespread adoption of VCCE as a path forward to building a better understanding of the mechanics of soft biological materials.