This advanced imaging technology was recently published in Light: Science & Applications. An US patent application has been filed for the innovation.
"CLAM allows 3D fluorescence imaging at high frame rate comparable to state-of-the-art technology (~10's volumes per second). More importantly, it is much more power efficient, being over 1,000 times gentler than the standard 3D microscopes widely used in scientific laboratories, which greatly reduces the damage done to living specimens during scanning," explained Dr Tsia.
The heart of CLAM is transforming a single laser beam into a high-density array of "light-sheets" with the use of a pair of parallel mirrors, to spread over a large area of the specimen as fluorescence excitation.
"The image within the entire 3D volume is captured simultaneously (i.e. parallelized), without the need to scan the specimen point-by-point or line-by-line or plane-by-plane as required by other techniques.
Such 3D parallelization in CLAM leads to a very gentle and efficient 3D fluorescence imaging without sacrificing sensitivity and speed," as pointed out by Dr Yuxuan Ren, a postdoctoral researcher of the work. CLAM also outperforms the common 3D fluorescence imaging methods in reducing the effect of photo-bleaching.
To preserve the image resolution and quality in CLAM, the team turned to Code Division Multiplexing (CDM), an image encoding technique which is widely used in telecommunication for sending multiple signals simultaneously.
"This encoding technique allows us to use a 2D image sensor to capture and digitally reconstruct all image stacks in 3D simultaneously. CDM has never been used in 3D imaging before. We adopted the technology, which became a success," explained by Dr Queenie Lai, another postdoctoral researcher who developed the system.
"Since CLAM imaging is significantly gentler than all other methods, it uniquely favours long term and continuous 'surveillance' of biological specimen in their living form. This could potentially impact our fundamental understanding in many aspects of cell biology, e.g. to continuously track how an animal embryo develops into its adult form; to monitor in real-time how the cells/organisms get infected by bacteria or viruses; to see how the cancer cells are killed by drugs, and other challenging tasks unachievable by existing technologies today," Dr Tsia added.
CLAM can be adapted to many current microscope systems with minimal hardware or software modification. Taking advantage of this, the team is planning to further upgrade the current CLAM system for research in cell biology, animal and plant developmental biology.
MEDICA-tradefair.com; Source: The University of Hong Kong