NTU MSE June 2014: DAY 8

Today we saw the result of the staining test. We washed the samples with PBS twice to wash away the staining solution. Then, PBS was added to keep the solution moist to prevent the cells from drying up.

We then used a microscope to see the cells, the aged cells were stained with a greenish blue colouration while the new cells were not stained.

New cells with a relatively massive crystal of x-gal!

Stained aged cells

We then saw another experiment being conducted. This experiment creates cells arranged in a pattern. This pattern allows stem cells to be made into long chains. This can be used to replicate the cells in the heart muscles. This is to come closer to the ability of solving the problems of muscle damage after a heart attack, as the muscle do not readily repair itself like in other tissues.

This also brings us to the topic of 3D printing of cells. It brings us closer to that future, yet the problem is to align cells into a nice pattern just like our organs and tissues.

Back to the pattern printing, the process includes a red solution to be added to the cell. UV light is then used to provide sufficient energy to achieve the activation energy required for binding to occur. This solution allows the cells that are on the pattern to bind to the treated gel.

Prior to stamping the pattern, a hard silicon gel with microscopic imprints is added in an organic solvent and ultrasound is used to agitate the solution and wash away any minute dust particles or impurities on the silicon. The silicon contains the pattern required and is stamped on the PA-gel with mixture in between. He then put it under weights for 40-50 minutes to create the micropattern onto the PA-gel.

Later in the afternoon, we were brought to the lab and introduce to the concept of electrospinning. It involves bringing a solution of dissolved fibre particles to such a high electrical potential that the solution repels itself and is effectively "shot" out of a fine nozzle onto the oppositely charged spinning plate to be collected as a long and extremely thin thread. In fact, the thread was so thin we could barely see it during the spinning and we had to observe it under the microscope instead! In order to prepare the solution, the fibre particles were dissolved in a solution of chloroform. We were told the process would take 7 hours! Thankfully, a solution was already prepared a day before so we didn't have to wait. While waiting the the solution to be entirely spun out, our mentor introduced us the the instruments used in the lab such as a vacuum pump for vacuum drying samples, an spinning agitator for dissolving solutes, a giant centrifuge and also an autoclave machine for sterilizing any biohazardous waste or equipment! He also brought us a sample of hydrophobic material that as its name suggests, is able to prevent water from sticking to the surface and causes them to form spheres that roll off quickly.

Spinning in progress!