What is INBT?

At Johns Hopkins University, the Institute for NanoBioTechnology is sort of a strange hybrid animal— a unique entity in academia. Founded in 2006, we are a virtual center that draws faculty membership from four divisions – the medical school, engineering school, school of arts and sciences and from public health.

Four different divisions comprise INBT.

Four different divisions comprise INBT.

Two faculty members, Peter Searson, the Joseph R. and Lynn C. Reynolds Professor in the Department of Materials Science and Engineering, and Denis Wirtz, the Theophilus H. Smoot Professor in the Department of Chemical and Biomolecular Engineering, started INBT. They thought it made sense to combine the efforts of people in engineering with people working in the medical and basic sciences as well as in public health to better solve problems in health care. We have more than 220 affiliated faculty members. There are no other centers or institutes at Hopkins with as many participants from as many different disciplines.

Any faculty member can become a member of INBT; they just have to have an interest in incorporating nanobiotechnology—or science at the scale of just a few atoms—into their research. Researchers at INBT are working on everything from drug delivery systems to solving problems in basic science and engineering using nanobiotechnology.

Physically, INBT is located on the Johns Hopkins Homewood campus in Suite 100 of Croft Hall. That’s where our administrative offices are and some of our faculty members have laboratories in this building. But our research occurs wherever our faculty members are working, and much of that is at the School of Medicine. In fact, nearly half of our members come from the medical school. Faculty members in other divisions are mostly likely collaborating with people at the School of Medicine.

At INBT, we search for funding opportunities for our members and offer small seed grants that help collaborators launch projects. Sometimes these projects are later funded and sustained by larger federal grants. We feel good about helping new ideas find “legs”.

In addition, we train up-and-coming scientists and engineers from high school through the postdoctoral level in our affiliated labs. These include short-term summer programs as well as highly competitive government funded research experiences and fellowships that last several years. INBT is educating the next generation of researchers who will solve problems at the interface of science, engineering and medicine. Our graduate students who fulfill specific requirements are awarded a Certificate of Advanced Study in NanoBioTechnology.

We have global outreach programs as well. INBT has funded research teams to India and Tanzania to solve engineering problems in local communities. Sometimes the challenges are medical, and sometimes they are purely engineering, but the teams much use local materials and resources to accomplish their goals.

Finally, we have industry affiliations. By working with companies in the U.S. and worldwide, we are developing training opportunities for our students that result in the development of new knowledge and hopefully new patented and marketable products. We don’t want to keep our innovations in the lab; we want to bring them to people for the benefit of humankind.

So in a nutshell, that’s what INBT is all about. To learn more about some of our specific programs and about some of the other centers we have launched under the INBT “brand”, read the other articles in this series. You can also watch this video about INBT. 

This article is part of a series of brief reports on INBT and its different components and programs. Together, we hope these articles will help readers inside and outside of the Johns Hopkins University community to understand what INBT is and what we do.

 

Definition: What is Brownian Motion?

Not all bumper cars are created equal. Somehow I always pick the one with a sticky gas pedal and become the object of torment for my opponents. This is essentially what happens to microscopic particles when you stick them in a jar of water. The microscopic particle is a massive bumper car stuck in the middle of the rink surrounded by a bunch of tiny super-charged bumper cars, water molecules. The water molecules are all crashing into the poor, defenseless particle at once, and this makes it move. If you were to watch the particle, it would look like it’s moving in random directions for no apparent reason. A botanist named Robert Brown (hence the name Brownian Motion) watched pollen grains doing this in water with a microscope almost 200 years ago.

Click on this image to watch "Dark Field Video Microscopy of 100 nm Gold Nanoparticles"

Click on this image to watch “Dark Field Video Microscopy of 100 nm Gold Nanoparticles” by Gregg Duncan

It turns out actually that this process isn’t entirely random. How fast particles jiggle around is dependent on a few things. As the particles get bigger, they will move slower because more water molecules have to gang up on it to push it around. We can also give the water molecules more energy by increasing the temperature. At higher temperatures, the water molecules will move around faster and bang into the particle with more force that will make the particle move more quickly. It’s also important what kind of fluid the particle is immersed in, as you may or may not know from experience, it’s a lot easier to swim through water then something more viscous, or “thicker” like molasses. So if you take these few things into consideration, we can predict how big the random jumps particles make pretty accurately.

So then how do we measure how fast they move? Well, you need some way to watch the particles move around and this is still done the same way Robert Brown did back in the day with a microscope. Then you can watch the particle for awhile and write down where it went over time. You’ll see that if given x amount of time, the particle on average moves about the same distance. In fact, if you plot the average distance the particle moves versus time, it’s a straight line. The slope of that line is what we use to figure out the diffusion coefficient of the particle, and this tells us how fast or slow the particles will move.

Luckily in my lab, we have fancy cameras attached to our microscopes to make movies of particles moving around. I have a video here I took recently of some gold particles I was messing around with. I used a technique called dark field microscopy, which is a nice way to image really, really tiny particles like these that can’t be seen in normal microscopes. We’ve also written particle tracking software that does all the number crunching for us to figure out how fast the particles are moving. It is important for us to know how fast particles are moving as they approach each other for instance, when we try to build crystals out of them or as they approach a surface, like a cancer cell.

Story by Gregg Duncan, a Ph.D. student in the Department of Chemical and Biomolecular Engineering with interests in nanoparticle-based biosensing and drug delivery.