Hello, everybody! “Long time no see”!

I have just spent a whole night on my dissertation (or exactly the first chapter of my dissertation), and I’m going on after finishing this post. During the past month I have no time to express my feeling (mostly a depressed one, with a little surprising joy, though). The dissertation is excellent enough in setting me in torture besides politics (and it is always a comfort that NN is the only e-place I know where politics is absent). Now, A new conclusion besides those I have made/fabricated in my dissertation is that, based on my experiment, spending a whole night on something is equally effective in the deterioration of my health as well as the progress of that thing – I nearly finished something that I’ve spent weeks on.

Something else happened during this period (don’t worry I won’t mention politics):

BAD About ten samples of DSC were terribly delayed because of shortage of bowls (the nano-bowl in my last post). New bowls won’t arrive in two weeks. And deadline of my dissertation, which must include the DSC results of these samples, is the end of this month.

GOOD To add some more pages to my dissertation I did additional electron microscopy, and the results were exceptionally good.

BAD My hard drive corrupted.

GOOD I bought a notebook (or, an ‘Entertainment PC’ as it reads, although I wasn’t entertained much on it). It’s an HP dv2804tx, with Intel Centrino Dual Core CPU and a nVidia stand-alone graphic card. I can bring it to the Library and search for references in situ when typing my dissertation, otherwise I have to photocopied the references and remember/review what they are about/for at another time.

Now I’m going to talk about my celebrating EM photos!

Transmission electron microscopy of micelles of poly(ethylene glycol-b-polylactic acid) diblock copolymer of different molecular weight

this title includes too many of’s and lacks professional terms. Try revising it into this:

Visualization of the nano-structures self-assembled by poly(ethylene glycol-b-polylactic acid) diblock copolymer via transmission electron microscopy

Now the title contains only one of but more hot terms, including a ‘via’ in italic which is cool.

Equipment: JEOL JEM-100cx II

This is a pretty old model of TEM. I love old instruments – old ovens, old glasswares (which use rubber stoppers rather than ground-glass ones), old wooden shelves, and old TEM – how cool! This TEM has been minimized in digital technology. All control panels are button-based. And they create a large noise when pressed. Photos are taken with films.

I’m not the only one in the world that love this TEM model. See here, and here.

Sample Preparation: Micelle solution was prepared as follows. Block copolymer was first dissolved in 0.5ml of THF with stirring at 50°C for 10 min. Then 10ml of filtered (0.45μ) pure water (Milli-Q) was added dropwise to the solution. The mixture was heated to boiling for 3 min to evaporate the THF, then quench to room temperature with cold water with stirring.

A Cu-mesh with carbon membrane was immersed into the micelle solution stained with citric acid and dried at room temperature before TEM investigation. TEM was performed at an accelerating voltage of 80kV.

And finally… the photos:
1. 40000x

2. 100000x

3. 100000x

4. 100000x

Comments: The actual size of the photos are about 3.25×4”, so the tubes in the photos are about 30-40 nm in width. All the photos above are from a copolymer sample with the weight ratio of the two blocks equaling 1:1. Some short, worm-like micelles are also observed around the tubes. They might be the precursor micelles which coalescence into longer tubes. Another sample with the ratio of 1:3 self-assembled into spheres rather than tubes (photos not finished).

Conclution: Although different morphologies of block copolymer micelles have been well documented (no references sorry. I am sick of finding the very two or three PDF files from a thousand ones to support my assertion), this kind of block copolymer is mainly reported to used in spherical micelle for drug delivery due to its biocompatibility and biodegradability. It is thus of great interest whether drugs carried by tubes or other shapes of morphology may be released in different ways.

I made the first photo into 4 colored wallpapers: red, green, blue, purple (please click ‘Download Photo’ to get the full size version).