Lay Man
Somehow I like the idea to make this blog more "daily living". I know a lot of people do, but in many sense...I just didn't; and, I think, after all, why not?
It's easier to write, and it'd be good to just jot down what's inside - rudimentary and without formulations. I might as well be more "lay-man", for I am, but there are times I'm tempted to appear not so.
So, now, I am babbling from the laboratory. Pulling myself out a bit from a pool of actin images.
The TIRF system worked fantastically. I feel that the idea behind this microscopy is a beauty. TIRF stands for Total Internal Reflection Florescence. When a laser beam strikes on the bottom of a cover slip, incident at or over the critical angle, it is total internally reflected. However, although there appears no visible light on the other side, there is an evanescent wave propagating and decaying exponentially. It carries energy too (is the Poynting vector non-zero??), which is able to excite the florescence label attached to the sample - we use Rhodamine which shows up in the orange channel.
Since the evanescent wave is effectively about 100nm thick, only the sample near the bottom/cover slip is excited. It reduces a lot of background noise and enhances contrast. You will see marginal florescent sample "switched" on & off. And, well, it's simple to setup and use (surely apart from the laser alignment, which Nikon did way before I started working here). Simplicity and beauty - isn't it wonderful?
posted by Campion @ 4:06:00 PM
