Congratulations to Rashad Baiyasi, graduate student in electrical and computer engineering (ECE) on receiving the top grade in ELEC 599 this past spring, for his presentation, “Characterization and Localization of Complex Fluorescence Point Spread Functions”. ELEC 599 is a PhD qualifier course taken by ECE students in their first year of graduate study that allows them to begin research early in the program.
Baiyasi’s research, done with faculty advisor Christy Landes of Chemistry, focuses around super-resolution microscopy and plasmonic particles. Landes says above all, his project challenges the notion that super-resolving distorted images is impossible.
One of the powerful technologies the lab uses is super-resolution microscopy. Landes explains that the importance of this super-resolution imaging cannot be overstated. “It provides the ability to take detailed pictures of nanoscale objects in native environments, a goal previously considered impossible,” she says.
Baiyasi says a potential application for his work is generating super-resolution images of catalytic hotspots on nanoparticles. Super-resolution microscopy can resolve features below the diffraction limit of light by analyzing the images formed by individual emitters. These images are distorted when a nanoparticle’s plasmon interacts with light emitted from a nearby fluorescent molecule. So the same strong field interaction with incoming light that makes them such promising photocatalytic substrates also distorts the microscope image so much that current super-resolution algorithms fail.
Baiyasi has successfully developed a model by which to simulate and reproduce the distorted images, an important contribution for this field.
"By using certain techniques we can make the emitters blink on and off so that only one is active in an area at a given time. Then we can take a series of pictures with different emitters active to build a super resolution image,” Baiyasi says.
“Applied to biological imaging, researchers can look inside cells and resolve sub-diffraction limit details by fitting the well-behaved PSFs that normally occur. When we apply this to metal nanoparticles we need to be able to fit the distorted PSFs. I came up with my own model, and after fitting I could see different components and definite trends,” Baiyasi says. He hopes to continue the research and to apply machine learning techniques to it.
Landes hopes the same. “He hypothesizes that by applying the latest machine learning methods, it will be possible to train an algorithm to recognize which complicated images are caused by which nanoscale interactions and thereby construct a correct super-resolution image of nanoparticle surface interactions. If he succeeds, he will have solved a serious and current problem in the quest to nano-engineer surface activity, while also demonstrating the value of modern signal processing to basic research problems,” she explains.
“I think it is a very interesting project and I was lucky because I was able to apply a lot of what I was interested in such as optimization, plasmonics, data analytics, and so on. This is one project I would like to continue with; right now it’s more of a proof of a more advanced project,” Baiyasi says.
Baiyasi will continue research in the area of Photonics, Electronics and Nanodevices, studying fluorescents and plasmonic nanoparticles. “I think that plasmonic nanoparticles have really exciting potential applications. They’re something that humanity has unwittingly used for a long time – for example, gold nanoparticles in glass change glass to a red color. People working in stained glass didn’t know why exactly the glass turned red, but we know now it is due to those specific plasmonic particles in the glass. So there are very visible results and many potential applications, but we still have a ways to go in fully understanding the field,” he explains. “There is a potential for digging deeper: learning not just what happens but why it happen.
Baiyasi also mentions that communication was essential to his success in ELEC 599. “We are thrown into the deep end and told, “do research”, which can be overwhelming if you don’t have a lot of experience. Communicating with your classmates and people who have done this before is key, not just for help, but also for support,” he said. “I would also say it’s important to reevaluate your goals based on your progress. Every couple of weeks I would sit down and see where I was and where I needed to go. With my research there were a lot of potential directions, and I needed to choose on my own which direction to go. I couldn’t just go ask my advisor what to do next- it was important to rely on myself to determine what was possible.”
Landes is confident in his work. “Rashad accomplished all of this in just a few months,” she says. “He taught himself the programming language, the background on nanoparticle plasmonics, and the optics necessary to simulate the images. He works well with others to solve problems, and is a great team player. His communication skills are top notch, and I count myself lucky to work with him.”
Baiyasi said he has enjoyed his time at Rice thus far and is looking forward to continuing his research work. “I really like Rice, it’s a beautiful campus with great faculty. I’ve been very lucky, made a lot of strong friendships, and I’m excited to continue to learn with this team and contribute to the scientific progress being made here.”