School of Physics and Astronomy, University of Exeter, Streatham Campus, EX4 4QL, Exeter, UK.
Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory, Harwell Oxford, OX11 0QX, UK.
Sci Rep. 2018 May 30;8(1):8379. doi: 10.1038/s41598-018-25465-x.
Optical properties of biological tissues can be influenced by their temperature, thus affecting light transport inside the sample. This could potentially be exploited to deliver more photons inside large biological samples, when compared with experiments at room temperature, overcoming some of difficulties due to highly scattering nature of the tissue. Here we report a change in light transmitted inside biological tissue with temperature elevation from 20 to 40 °C, indicating a considerable enhancement of photons collected by the detector in transmission geometry. The measurement of Raman signals in porcine tissue samples, as large as 40 mm in thickness, indicates a considerable increase in signal ranging from 1.3 to 2 fold, subject to biological variability. The enhancements observed are ascribed to phase transitions of lipids in biological samples. This indicates that: 1) experiments performed on tissue at room temperature can lead to an underestimation of signals that would be obtained at depth in the body in vivo and 2) that experiments at room temperature could be modified to increase detection limits by elevating the temperature of the material of interest.
生物组织的光学性质可以受到其温度的影响,从而影响样品内部的光传输。与在室温下进行的实验相比,这可能会被利用来在大型生物样本中传输更多的光子,克服由于组织高度散射的性质而导致的一些困难。在这里,我们报告了光在生物组织内部随温度从 20°C 升高到 40°C 的传输变化,表明在传输几何中探测器收集的光子数量有了相当大的增强。对厚度达 40mm 的猪组织样本的拉曼信号的测量表明,信号强度会有 1.3 到 2 倍的显著增加,这取决于生物学的可变性。观察到的增强归因于生物样本中脂质的相变。这表明:1)在室温下进行的组织实验可能会导致对体内深处获得的信号的低估;2)可以通过升高感兴趣材料的温度来修改室温下的实验,以提高检测限。