Biomedical Engineering Personal Statementfor Oxford & Cambridge

When the first mRNA Covid-19 vaccines were authorised in December 2020, I understood the medical importance long before I understood the engineering problem inside them. News reports focused on efficacy and rollout, but what stayed with me was that the genetic instructions were so fragile they had to be carried in lipid nanoparticles. I wanted to know how something as unstable as mRNA could be protected, delivered into cells and released where it could work. That shifted my view of treatment. Success depended not only on identifying the right molecule, but on designing the material and delivery system that made the molecule usable at all. Biomedical engineering drew me in because it works where biology is unpredictable but design still has to be precise. I want to study biomedical engineering because it lets me pursue that tension between elegant theory and difficult application. At university, I want to explore biomaterials and drug delivery in more depth, especially how engineers design systems that remain reliable when biology is variable and hard to predict.

That interest became more concrete through topics I was studying. Diffusion in chemistry and membrane transport in biology had seemed straightforward in class, but in drug delivery they carried consequences: a treatment can be sustained, localised or lost depending on how a substance moves through a material. To understand that better, I read sections of W. Mark Saltzman's Biomedical Engineering: Bridging Medicine and Technology and worked through MIT OpenCourseWare lectures on biomaterials and controlled release. What stayed with me was the trade-off at the centre of the field. A material has to be strong enough to survive handling, porous enough to release a drug, and biocompatible enough not to trigger the wrong response. I had initially assumed that the best biomaterials would simply imitate nature more closely. The more I read, the more I saw that design often means choosing between imperfect options. That project became the basis of my EPQ on controlled release systems and why hydrogels remain attractive despite their limitations. I focused on how mesh size, swelling and degradation affect diffusion, and on why materials that perform well in vitro may behave differently once mechanical stress and variable physiology are introduced. The hardest part was resisting the temptation to treat every paper as evidence of progress. A review might describe a scaffold as promising, but when I traced the references I often found short timescales, simplified conditions or unresolved questions about reproducibility. That did not make the subject less interesting. It made it more demanding, because it showed me that biomedical engineering depends on careful measurement, not just clever design.

Outside my formal studies, I wanted to test some of those ideas for myself, so I used a CREST Gold project to investigate how alginate hydrogel beads could act as a model for controlled release. Because my sixth-form college had no specialist biomedical lab, I kept the system simple: sodium alginate cross-linked in calcium chloride, food dye as a stand-in solute, a school colorimeter, and Python to plot release curves. By varying polymer concentration, I was trying to see how internal structure might affect diffusion. I expected denser beads to slow release, but the results were messier than that. Some smaller beads released faster than less concentrated ones because bead size altered the surface-area-to-volume ratio, and some batches were inconsistent because my droplet formation was uneven. That stopped me claiming a tidy conclusion that the method had not earned. Repeating trials and tightening the procedure taught me that a biomedical device is difficult because small variations in manufacture can overwhelm the pattern you think you are measuring. It was useful because it forced me to separate expectation from evidence.