Weeks 3 and 4: Initial Microsphere Fabrication

Hi everyone and welcome back to my blog! I have officially entered into the more hands-on portion of my senior project research. These past 2 weeks I focused the majority of my time in the lab on carrying out the methodology I created earlier. 

The first step to create the microspheres through Silk Fibroin (SF) and Polyvinyl alcohol (PVA) phase separation was to make separate SF and PVA solutions. The SF solution was made by combining deionized water and lyophilized SF powder, and the PVA solution was created similarly by combining PVA powder and deionized water. The first issue I ran into this week was with creating the PVA solution. After a long time mixing the PVA solution (using a magnetic stir bar), I noticed that the PVA would not dissolve and would rather clump up. This was a problem that was really important to address because agglomerations in the solution could result in having irregularly formed and shaped microspheres. After researching this, I realized that the problem with the PVA dissolution was coming from the molecular weight of the PVA as its solubility is dependent on its molecular weight. After discussing this with my mentor, I was able to order new PVA with a lower molecular weight that resulted in much better dissolution.

After the solutions were created, they were mixed, poured into petri dishes, and dried to create films. These films were then dissolved into solutions and centrifuged, then sonicated. See below for some photos of the whole process!

In the next weeks, I will be able to analyze and characterize the microspheres I have made from these initial trials of the methodology. Based on what I see, I will adjust the protocol accordingly. I will update you all next week!