More insights into how neural circuitry works in mammals would enable a better understanding of our brain and its functions. Investigations pertaining to such studies require assessing brain activity using a high-resolution microscope. The requirement here is for a microscope that extends resolution high enough for clearly analyzing specific neurons.
The recently innovated two-photon fluorescence microscope could be the solution for these challenges. The lab of UC Santa Barbara Associate Professor, Spencer LaVere Smith is now the hub of research in this aspect.
The ‘Nature Communications’ Nov.17 issue reports the development of an innovative microscope which is technically referred to as “the Dual Independent Enhanced Scan Engines for Large Field-of-view Two-Photon imaging (Diesel2p)’, by Steve and a team of researchers.
This newly invented microscope comes with the largest, i.e, about 25 sq. mm field of view, as compared to similar devices. As a result, researchers utilizing this microscope are able to receive subcellular resolution of several sections of the brain.
This innovative microscope incorporates a range of custom-manufactured and custom-designed elements. These include the scan lens, optical relays, objective lens, tube lens, and optical relays. The device is also being widely adopted for its capacity to extend high-speed imaging of the much complex neural activities even in the highly widespread regions of the brain.
Here are the critical features of the two-photon microscope:
- The highly strong lasers fuelling the two-photon imaging systems cost about $250,000.
- These lasers are what enable the ultra-intense and ultra-fast pulses of light that are about a billion times brighter if you compare them with the sunlight.
- These pulses of light are about 0.0001 nanosecond duration.
- The microscope scans two regions with varying imaging parameters together.
- The microscope allows varying scan parameters to be leveraged for both beams.
- The two-photon microscope employs a different type of light. There is only a single point of light without any cones.
- The single-beam light extends sharp focus and eliminates all of the out-of-focus lights from going near the imaging lens.
“With normal optical imaging, you can see only the very top of the brain. Two-photon imaging allows us to image deeper down and still attain sub-cellular resolution,” adds Steve.