Korean scientists have developed the world's first ultrasound induced laser scanning microscope. This technology can use the bubbles temporarily generated by ultrasound to observe biological tissues in more depth and detail, which is expected to promote the development of biological science research and clinical practice. Relevant research was published in the latest issue of Nature Photonics.
Optical imaging and treatment technologies are widely used in life science research and clinical practice. However, due to the light scattering phenomenon in biological tissues, the light transmission rate is low, which leads to the inherent limitations of image acquisition and processing in deep tissues, seriously hindering their widespread use.
In 2017, a team led by Professor Zhang Jinhao (transliteration) of the Department of Electrical Engineering and Computer Science of the Qingbei Academy of Science and Technology in Daqiu proposed a solution: use the micron sized bubbles that are usually observed when biological tissues are exposed to high-intensity ultrasound. The bubbles generated temporarily by ultrasonic wave will cause light scattering in the same direction as the incident light, thus increasing the penetration depth of light. Based on this principle, researchers developed a technology and began to focus on expanding the application range of optical imaging technology using ultrasonic wave to induce bubble generation.
Confocal fluorescence microscope can selectively detect the fluorescence signals generated on the optical focal plane, and provide high-resolution and high contrast images of micro biological tissues (such as cancer cells), becoming the most widely used equipment in the field of life science research. However, due to light scattering in tissues, when the depth exceeds 100 μ m, the focus of light will become blurred, which severely limits the application and effectiveness of confocal fluorescence microscopy.
To this end, the joint research team used ultrasonic technology to create a bubble layer in the area with dense bubbles (density of 90% or more) in living tissue, and kept the bubbles generated when acquiring images. In this bubble layer, the propagation direction of photons will not be distorted. Experiments show that light focusing can be realized even in deeper biological tissues. In addition, by applying this "ultrasound induced tissue transparency" technology to the confocal fluorescence microscope, they developed the first ultrasound induced optical clear microscope, which has an imaging depth of 6 times that of the traditional confocal microscope, and will not cause any damage to biological tissues.
Zhang Jinhao said: "The new technology obtained in this study will be applied to various optical imaging technologies, including multiphoton microscopy and photoacoustic microscopy, as well as several optical therapies, including photothermal therapy and photodynamic therapy."
Source: Science and Technology Daily
