Non-invasive optoacoustic probing of the density and stiffness of single biological
Non-invasive optoacoustic probing of the density and stiffness of single biological
复制标题
DOI：
10.1063/1.4769294
复制
发表时间：
2012-12-15
影响因子：
3.2
通讯作者：
Audoin, B.
中科院分区：
文献类型：
--
作者：
Dehoux, T.;Audoin, B.
近年来，利用超短激光脉冲相干产生千兆赫兹声波，已经证明能够以微米级分辨率探测植物细胞和模拟细胞的软微物体的声速，为单细胞生物学开辟了巨大的潜力。然而，当使用基于激光的设置时，在生理条件下操纵生物介质通常是一个技术挑战。在本文中，我们提出了一种新的光声生物换能器，该换能器由透明散热器上溅射的薄金属膜组成，可以显著减少激光诱导的细胞应力，并提供多种光学结构。特别是，通过利用样品-换能器界面处的声反射系数和光声相互作用，可以同时探测样品的密度和可压缩性。利用基于希尔伯特变换和小波变换的特别信号分析，可以精确地测量参考流体的这些量。在单个植物细胞中进行的类似分析也表明对传感器-细胞界面状态的高度敏感性，特别是对包裹细胞液泡的质膜的存在。(C) 2012年美国物理研究所。[http://dx.doi.org/10.1063/1.4769294]
Recently, the coherent generation of GHz acoustic waves using ultrashort laser pulses has demonstrated the ability to probe the sound velocity in vegetal cells and in cell-mimicking soft micro-objects with micrometer resolution, opening tremendous potentialities for single-cell biology. However, manipulating biological media in physiological conditions is often a technical challenge when using a laser-based setup. In this article, we present a new opto-acoustic bio-transducer composed of a thin metal film sputtered on a transparent heat sink that allows reducing importantly the laser-induced cellular stresses, and offers a wide variety of optical configurations. In particular, by exploiting the acoustic reflection coefficient at the sample-transducer interface and the photoacoustic interaction inside the transparent sample, the density and compressibility of the sample can be probed simultaneously. Using an ad hoc signal analysis based on Hilbert and wavelet transforms, these quantities are measured accurately for a reference fluid. Similar analysis performed in a single vegetal cell also suggests high sensitivity to the state of the transducer-cell interface, and notably to the presence of the plasma membrane that encloses the cell vacuole. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4769294]