LIPhy, UGA/CNRS, 140 rue de la Physique, 38402 Saint Martin D'Hères, 38058 Grenoble Cedex 9, France.
Soft Matter. 2017 Jun 14;13(23):4210-4213. doi: 10.1039/c6sm02887j.
Diffusion and transport of small molecules within hydrogel networks are of high interest for biomedical and pharmaceutical research. Herein, using fluorescence correlation spectroscopy (FCS), we experimentally showed that the diffusion time in the hydrogel was directly related to the mechanical state (compression or swelling) and thus to the volume fraction of the gel. Following this observation, we developed cell-like barometers in the form of PAA microbeads, which when incorporated between cells and combined with a diffusion-based optical readout could serve as the first biosensors to measure the local pressure inside the growing biological tissues. To illustrate the potential of the present method, we used multicellular spheroids (MCS) as a tissue model, and it was observed that the growth-associated tissue stress was lower than 1 kPa, but significantly increased when an external compressive stress was applied.
水凝胶网络中小分子的扩散和传输在生物医学和制药研究中具有重要意义。在此，我们使用荧光相关光谱（FCS）实验表明，水凝胶中的扩散时间与机械状态（压缩或溶胀）直接相关，从而与凝胶的体积分数有关。基于这一观察结果，我们开发了以 PAA 微球为形式的类细胞压力计，当它们被整合到细胞之间并与基于扩散的光学读出相结合时，可以作为测量生物组织中局部压力的第一个生物传感器。为了说明本方法的潜力，我们使用多细胞球体（MCS）作为组织模型，观察到与生长相关的组织应力低于 1kPa，但当施加外部压缩应力时，组织应力显著增加。
