At A Glance
Hyoung Jin “Joe” Cho, Ph.D.
Assistant Professor, Mechanical, Materials & Aerospace Engineering, University of Central Florida
Education: 2002 — PhD, MEMS and BioMEMS, University of Cincinnati,
1991 — MS, materials engineering, Seoul National University, Seoul, South Korea.
1989 — BS, material engineering, Seoul National University.
Previous Experience: 1993-1997 — Research engineer, Korea Electronics Technology Institute.
Joe Cho, 37, has been an assistant professor at the University of Central Florida for a year and a half, and in that short period of time, he has collected nearly $500,000 in grant funding for biosensor-based research and development projects.
An assistant professor in mechanical, materials, and aerospace engineering at the university, Cho has an ongoing research project funded by NASA and the University of Florida to develop a disposable microbial sensor for water-quality monitoring using a generic biosensor platform.
He recently earned a five-year National Science Foundation faculty early career development award for approximately $400,000 to develop and miniaturize surface-plasmon-resonance based sensors with integrated microfluidics for in situ monitoring of biomolecular activities. NSF describes the award as one of the foundation’s most prestigious awards for new faculty members.
Cho, who heads UCF’s Laboratory of Nanofabrication and BioMEMS, earned his PhD in electrical engineering from the University of Cincinnati with a concentration in MEMS (microelectrical mechanical systems) and BioMEMS. He studiied under Chong Ang in the school’s Microsystems and BioMEMS Laboratory, andcompleted his work as a research associate in a DARPA-funded project developing plastic-based structurally programmable microfluidic biochips for clinical diagnostic applications.
Now, in an office located just east of Orlando, a short walk away from the school’s University Technology Center and its Biomolecular Research Annex, Cho sits under a small printed sign that draws a parallel between SPR and the biblical story of the burning bush.
Last week, Cho spoke to BioArray News about his work in biochips and biosensors.
I can’t help but notice above your desk you have a quote from the bible, and a comparison with surface plasmon resonance. Could you explain that?
It says: ‘A blazing fire from the midst of a bush. He looked, and behold, the bush was burning with the fire, yet the bush was not hot. [To explain] the burning, it’s a kind of plasma, it’s burning from the surface, and then, there was a voice. Voice is resonance. Somehow, this bible verse clicked for me.
Let’s talk about your research projects. The first, which is funded by NASA and the University of Florida, is a microbial sensor?
We are using a microorganism as part of a sensing platform for monitoring water quality. Micro biosensors in the market take a standard five days to measure; we think this can provide results within an hour. We are using yeast or bacteria as the material for sensing. Both survive well under a toxic environment. They are immobilized on a surface and we use respiratory activity to measure them. It’s not quite new, but I’m trying to develop it on a smaller scale, at 1 centimeter by 1 centimeter. It’s a flow-through sensor that can be committed in line with water flow. We are getting some good results and from my point of view, it will be an improvement on existing sensing technology.
What can you tell me about your second project?
This will be an optic-based biosensor using surface plasmon resonance, which is one of the most frequently used, and will be the most frequently used technology in biology and chemistry for drug discovery and food safety inspection. My project is to reduce the SPR instrument on a small scale. The National Science Foundation funds the research, but I haven’t started yet. My idea is to eventually decrease the whole size of the instrument to the size of a palm-top PC, with integrated optics on the chips. The generation of light, the detection, and the microfluidics will be integrated onto a chip. The newly funded project, the micro SPR sensor with the integrated microfluidic component for in situ monitoring of biomolecular activities, that could be really interesting, if we are successful.
The funding comes from a competition among untenured professors across the US. It’s an honor to get that award, and somehow I got it this year, and it will start this summer. I’m collaborating with professors in optics, fluid mechanics and biomolecular science. This is an interdisciplinary and multidisciplinary research.
How did you get involved in this field?
I came almost directly from the graduate school at the University of Cincinnati, where my advisor was Chong Ahn, who is a pioneer in magnetic MEMS and sensors, and he directs his research into the bioMEMS area. He has some interesting stuff. He has a wristwatch blood analyzer, which is a military application. He is heavily funded from DARPA, at almost a $1 million per year. And he has kept doing it for six years.
Why did you select UCF to begin your career?
Because of the nice weather. This university is growing very fast; it’s one of the fastest growing universities in the US. We are not in the league of an Ivy, but we are catching up very well. And UCF has one of the top optics schools in the US, and we have a great optic program in engineering and we plan on cultivating the area of biomolecular science. We have three thrusts on this campus — biomolecular science, nanotechnology, and optics. But I believe others are doing the same thing.
I am teaching MEMS materials, and we have plans for courses related to BioMEMS and Micro systems.
How does your work relate to microarrays?
There are times when open fluidic chips, typically microarrays, can not be used and have to be enclosed with some kind of fluidic packaging. For this, there needs to be an inlet and an outlet and they should be interfaced. The problem with these things is that people are making microfluidics channels and containing things on silicon wafers, glass wafers or plastics. Finally, by the time they need to attach tubing, it becomes really problematic. People try a lot of different approaches — they try to do dry etching, making a deep hole and attach a tube and use glue. It’s not very efficient.
To communicate with the outside world from the chip itself, we are using standard-sized tubing. There isn’t any kind of standard to use for connections in microfluidics. So, what we can consider as a standard is tubing size. And there recently has been big progress in microinjection-molding where we can generate the microfluidic patterns that were not possible before. We can now attach standard tubing on one side, and on the other side, the microfluidic structure. That microfluidics structure can be replicated by microfabricating on the substrate, combining microelectronic-processing technology with injection-molding technology. The intention is that if we have this kind of thing in a series on one side, and these are standard, then in the middle, we have the freedom to make whatever microfluidic structures we want. Then, finally, it can be interconnected very easily.
It’s one suggestion that can solve the problem of microfluidic packaging. If we standardize microfluidic packaging with the interconnecting capability all in one body, then I can do some measurement at once without doing the attachment of tubing and gluing. This whole concept is to make a disposable sensor, in a cartridge, just like a microarray, to use once and then throw away.
I’m also looking at some opportunities in microarrays, but in that case, I would need a nice collaborator, as my background is not biology or genetics. I’m just a tool provider who is willing to work with biologists and chemists.
Where do you think things will be in four year in terms of biological sensors like you are using?
I think there is going to be an explosive amount of work in collaboration between biology, chemistry. I got a sign of that from attending a conference called Micro Total Analysis Systems, which was held last year in Sacramento, Calif., and this year will be in Malmö, Sweden. The total number of attendees grows exponentially, bringing a lot of people in mechanical engineering, and electrical engineering, biology and chemistry all together. And they are working together to make better microsystems for fluidics, handling and detection, sensing, and manipulation. The conference has grown so fast. The conference proceedings have two volumes and the total pages are more than 1,300. A few years back, it was a thin, thin book. In a few years, it’s will be simple enough for high school students.