Optical sensing of mechanical pressure based on diffusion measurement in polyacrylamide cell-like barometers.
Optical sensing of mechanical pressure based on diffusion measurement in polyacrylamide cell-like barometers.
复制标题
基于聚丙烯酰胺类电池气压计扩散测量的机械压力光学传感。
作者：
F. Ingremeau;M. Dolega;Joseph P. Gallagher;Irène Wang;Giovanni Cappello;Antoine Delon
小分子在水凝胶网络中的扩散和传输是生物医学和药学研究的重要内容。在此，使用荧光相关光谱（FCS），我们的实验表明，在水凝胶中的扩散时间是直接相关的机械状态（压缩或溶胀），从而凝胶的体积分数。根据这一观察结果，我们开发了PAA微珠形式的细胞样气压计，当将其结合在细胞之间并与基于扩散的光学读数相结合时，可以作为第一个生物传感器来测量生长中的生物组织内的局部压力。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，并且观察到与生长相关的组织应力低于1 kPa，但是当施加外部压缩应力时显著增加。
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.