Evolution of Optical Microscopes... Simultaneous Detection of 'Calcium Communication in Cells' Possible

[Asia Economy Reporter Junho Hwang] A microscopy technology capable of simultaneously observing living cells and the blood flowing around them in high definition has been developed by a domestic research team. This microscope, equipped with both spatial resolution for precisely observing still images and temporal resolution for finely dissecting the movement of objects, is expected to contribute to research related to microfluidic channels and calcium signal transmission.

Microscope for Precisely Observing Movement

Three-dimensional distribution of fluid flow surrounding cells cultured within a microfluidic channel.

The research team led by Professor Jung Jeong-hoon of the Department of Life Sciences at Ulsan National Institute of Science and Technology announced on the 18th that they developed a technique to control both the temporal and spatial resolution of structured illumination microscopy within a single image, and their related paper was recently published in the international journal Optica.

The team improved the drawbacks of structured illumination microscopy, a type of optical microscope. Optical microscopes use visible light to obtain magnified images of materials. Although they cannot see as clearly as electron microscopes, which can examine down to the atomic level, they have the advantage of being able to observe living subjects such as cells in three dimensions. Structured illumination microscopy observes the fine structure of materials through interference patterns formed by overlapping two structures composed of small patterns like a mosquito net on the surface. However, since it captures the subject’s appearance through multiple images, it has the disadvantage of being difficult to capture instantaneous phenomena.

The research team overcame this drawback by selectively controlling the amplitude of light according to the characteristics of the area to be imaged. For fluid regions where short intervals must be captured, they used amplitude-patterned light with high temporal resolution, and for cell parts requiring clearer images, they used amplitude-patterned light with spatial resolution. This allowed them to capture high-definition images of fine cells and the flow of surrounding fluid in a single frame. Using this technology, the team simultaneously observed the flow of fluid cultivating cancer cells and the micro changes in the cells caused by it.

Observation of Calcium Signal Transmission and More

Schematic diagram of the operating principle of the structured illumination microscope developed by the research team

First author Taesung Woo, a researcher in the Department of Life Sciences, explained, "Because the amplitude of light can be controlled within a single space, we irradiated plane waves around cancer cells where temporal resolution is needed, and sine waves on cell parts requiring spatial resolution, enabling us to obtain ultra-high-resolution images."

The research team evaluated that the possibility of simultaneously capturing the movement of calcium ions traveling back and forth inside and outside cells (temporal resolution) and the cellular changes caused by calcium ions (spatial resolution) has increased. Additionally, since the optical system is based on controlling the amplitude of light at frequencies above 10 kHz within a single space, it is explained that this can be applied to implement ultra-high-speed imaging systems.

Professor Jung Jeong-hoon said, "This is a meaningful study in that it simultaneously observed biological phenomena at different spatiotemporal scales, which were previously unobservable with existing microscopes, within a single image using the same microscope," and added, "It is expected to be applicable to research related to microfluidic channels and various biological and physical phenomena requiring high temporal resolution, such as calcium signal transmission."

This content was produced with the assistance of AI translation services.