Week 2: Methodology

Welcome to week 2 of my senior project research! This week I created my initial protocol for fabricating the Silk Fibroin (SF) microspheres loaded with lung surfactant. This methodology is not finalized but will be adjusted and optimized through iterations of my trials in order to improve the quality and characteristics of the produced SF microspheres.

In regards to my methodology, from my literature review, I determined that these lung surfactant loaded SF microspheres would be created best through a process of phase separation of SF with Polyvinyl alcohol (PVA).

This is because both natural and synthetic materials can be used to fabricate microspheres for delivery systems, but the use of only natural polymers (like Silk Fibroin) for drug delivery applications has been limited due to its inconsistent batch qualities and uncontrollable degradation rates. However, when combined with polymers such as Polyvinyl alcohol (PVA), the characteristics (drug loading and release properties) of the microspheres become suitable for drug delivery. Past research has demonstrated that the phase separation between PVA and SF is especially conducive in creating microspheres because of its simplicity and denaturing of potentially bio-incompatible organic solvents. In fact, microspheres formed with PVA are found to be more uniform in size (Feng et al., 2001). This process of phase separation between polyvinyl alcohol (PVA) and silk occurs spontaneously when the two polymer solutions are mixed and subsequently cast into films.

The protocol follows the steps that are illustrated below.

Rockwood, D., Preda, R., Yücel, T. et al. Materials fabrication from Bombyx mori silk fibroin. Nat Protoc 6, 1612–1631 (2011). https://doi.org/10.1038/nprot.2011.379

Now that I have created and reviewed my proposed methodology with my mentor, in the next few weeks I will begin to carry out my initial trials!

References:

Feng, S.-shen, & Huang, G. (2001). Effects of emulsifiers on the controlled release of Paclitaxel (Taxol®) from nanospheres of biodegradable polymers. Journal of Controlled Release, 71(1), 53–69. https://doi.org/10.1016/s0168-3659(00)00364-3