Seeing (Nano)Stars to Fight Disease: Carlos Matti's Internship

November 26, 2013

Carlos Matti, '14, is majoring in chemistry and minoring in cell and molecular biology, with a concentration in the Gerald R. Ford Institute for Leadership in Public Policy and Service; he is also a member of the Prentiss M. Brown Honors Program. He describes his summer internship experience below.

This summer, I was awarded a National Science Foundation–Research Experience for Undergraduates internship. This allowed me to spend two months working with biophysical chemist Laura Sagle at the University of Cincinnati.

Her lab researches nanoparticle biosensing. Specifically, we looked for ways to improve the sensitivity of current biosensing technology. We investigated the attachment of a model protein to gold nanostars. This research has deep implications for detection of specific proteins, such as those produced by people that have cancer, Alzheimer's Disease or the Human Immunodeficiency Virus (HIV). The protein that binds to the nanoparticles is relatively easy to detect and this has significant potential for making early detection more accurate and less expensive.

No Capping Agents

Attaching a protein or a virus to a nanoparticle isn't new technology, but the research in our lab was the first of its kind—trying to perform nanoparticle biosensing without a "capping agent." Capping agents help prevent nanoparticles from becoming one big blob of particles. But the downside is that the presence of the capping agent makes it more difficult for the nanoparticles to bind to other molecules. When the nanoparticles are free of capping agent, they have significantly more surface area that can attach to protein.

In the lab, my job was to take a small amount of nanostars and remove the capping agent during the course of a day. The number of biosensors that are created at the end of the process equates to about several raindrops of dark blue material. Only small amounts are made because of the time it takes to synthesize and attach protein to the nanostars, and the expense of the materials—a couple of teaspoons of the materials costs about $350.

I then attached huge molecules to the nanoparticles to act as a link from the protein to the nanoparticles. The process took about three to five days to test against well-studied biosensors. The biosensors we made were much more sensitive than nanostar biosensors in literature. That means that our biosensors should detect smaller amounts of disease proteins, which could mean much earlier detection of disease. This equates to more lives saved; the earlier you detect a disease, the easier it is to treat.

The largest frustration was simply interpreting the data from the instruments (ultraviolet-visible spectroscopy and surface-enhanced raman spectroscopy). Ambient room light interferes with the instruments' readings, making analysis complex. So I had to transfer data from the instrument to a computer and then analyze the data. I spent many days at the computer just translating the raw data into meaningful results.

‘What I Am Doing May Break Ground’

The most rewarding part was being part of a team that is finding a new path for future biosensing. Scientists have not carried out biosensing without using a capping agent succesfully. Even though it is difficult to interpret the results, I know that this difficulty arises from the fact that we are researching a new paradigm that could improve biosensing dramatically. There's still a lot to do before we can perform biosensing that is disease-specific. At the end of the day, though, I know that what I am doing may break ground in the field.

I've learned a lot about doing research at a large institution: the competition for funding, the demand to publish on a regular basis, the realization that all your effort has gone into something that probably won't work and you try again and hope you'll discover new knowledge.

I've had the opportunity to probe the minds of the graduate students, post-doctoral fellows and my research adviser to learn more about techniques and theory, and to broaden my understanding of conducting meaningful research. Further, this experience has helped me to figure out what purpose I want to live my life with. I'm applying to graduate school this fall to carry out similar research.