As a KGSP alumnus and a KAUST PhD graduate, Abdullah Bukhamsin is joining Caltech through the Ibn Rushd Fellowship, a prestigious partnership fostering cutting-edge collaboration between KAUST and leading global institutions. His work, spanning plant health monitoring and biomedical diagnostics, seeks to revolutionize how we detect early signs of stress in living systems. In this profile, Abdullah shares his path from Dhahran to Houston, KAUST to Caltech, and how he hopes to advance the next generation of sensor technology.

Could you tell us a little bit about your experience as a KGSP student and where you come from?

I originally come from Dhahran, a city more or less built around the Aramco campus. I started my involvement with KAUST back in 2012, where I interned for the summer at the Plant Science lab as part of the SRSI program. We got experience doing some hands-on research with the lab. I worked on transgenic engineering for more resilient crops, which made me want to go into bioengineering. In 2012, I finished high school and applied and got into the KGSP program as a Foundation Year student. During Foundation Year, I applied to several universities, and one of them was Rice University in Houston, Texas. I did my bachelor's there and did a little bit of research there too, also on plant science.

Then, I came to KAUST in 2018, and I completed my master's degree in electrical engineering because back then, KAUST didn't have a bioengineering or biomedical engineering program. Bioengineering is relatively a nascent field, especially in Saudi. So, the closest thing was electrical engineering. I worked on sensors that were attached to leaves to detect a certain pest called the red palm weevil that attacks date palm leaves in the Kingdom and elsewhere. After finishing my master's, I continued with my PhD at KAUST in a different class of sensors designed to detect hormone levels in plants to monitor their health status in the field. The goal was to detect multiple diseases or types of stress so farmers can intervene earlier and mitigate their commercial losses.

Now, I'm about to finish my PhD with the sensors at KAUST. I will hopefully be joining a lab at Caltech as a part of the Ibn Rushd Fellowship, where I hope to learn a bit more about physical chemistry specifically.

I want to go back to your experience with Rice. You're one of very few KGSP students who attended Rice University.

Can you tell us how your experience as a KGSP student at Rice helped you prepare for KAUST?
You're right. I was the only person from my cohort who went to Rice, and I think that continued for the four cohorts that followed. I never actually had any other KGSP student at Rice with me, so I was kind of alone for that period.

My experience at Rice is also something that I didn’t fully appreciate at the time. Looking back, the things that used to frustrate me now make sense and I understand why I had to go through them. Bioengineering at Rice was a broad major. We were more of a "jack of all trades, master of none." I took a bit of mechanical engineering, a bit of chemical engineering, and a bit of electrical engineering, but I never really specialized. Going through it, I felt like it wasn’t as technically competent or specialized as the other engineering programs. It was frustrating because when you talk to mechanical engineers, they’re all specialized, right? They know their thermodynamics, they know their mechanics, and while you know the basics, you can't go in depth.

However, we had this cool facility called the Oshman Engineering Design Kitchen (OEDK), where all engineering students were grouped together during our final year. Then, we were assigned an industrial project. Ours was sponsored by Abbott, the medical company. If I remember correctly, we were supposed to come up with a cheap way to diagnose diabetes without using the commercially available option, which were enzymatic transducers. That’s when I saw the payoff of knowing how to use machine parts, design and work on Polychlorinated biphenyls or “PCBs”, program microcontrollers, handle basic control systems in LabVIEW, and then bring everything together. That was the moment I appreciated the degree and understood why we had to take all these seemingly unrelated courses. I could actually speak with people from different backgrounds, integrate what they know with what I knew, and get this global view. Now, I don’t regret it.  

Going through the PhD, I finally got to specialize. I have both tools in my arsenal: I know a bit about what other people are doing, but I also got to specialize. That’s how I’ve come to think about my time at Rice.

What motivated you to continue to pursue a PhD after earning your master's at KAUST?

I had applied as an MS to PhD with the intention of continuing the PhD from the start. But a combination of circumstances, the Bioengineering Department opening after I finished my master's, then my transition from the Electrical Engineering Department into the Bioengineering Department, all funneled me into the PhD.

For the master's at KAUST, I spent most of it taking courses. The project I pursued in my master's was very small in scope, but it was enough to get a taste of research. I got to use some of the facilities at KAUST, the coolest of which is the clean room. I got trained in some of the instruments there, what can be achieved, what can be done using the instruments available at KAUST.

Since KAUST is just a graduate level institution, there are not many students, so these tools are readily accessible, but there is not much time to use them as a master’s student. I liked the project I was working on. I wanted to do more, and I wanted to explore more. That funneled me directly into the PhD.

Could you tell us a little bit about the research that you'll be conducting as a part of the Ibn Rushd fellowship?

My goal for this fellowship is to add new tools to the arsenal, so to speak. At KAUST, I got some experience in micro-fabrication, and then materials synthesis and materials characterization. But at the moment I have very little physical chemistry, and I feel like it is the best way to build on what I already have. The lab I hope to work with next year has a lot more experience with physical chemistry and density functional theory simulation, where they can simulate molecular interactions.

They also work on sweat sensors. I have not worked with sweat sensors before. I have only worked with plant sensors. But it would be nice to also get that in the tool belt and learn how to work with different mediums.

Transitioning between plant sensors and sweat sensors seems like a big jump.  Are they at all similar?

They can all be classified as electrochemical transistors. The sensing principle is the same, just the application is different. And you do not need ethical approval to work with plants, but you need it for animals and humans, so you can prototype faster.

What is the overriding mission for the research that you'll be doing? How do you envision your research contributing to sustainable agriculture and food security in the future?

My goal is to provide more information to the farmer in a more cost-effective manner. Right now, they rely mostly on remote sensing, using satellite hyperspectral cameras, or soil level sensors. These either detect what we call a phenotypical change, meaning a change that can be observed on the leaf or the plant itself, or they rely on environmental factors. These solutions do not detect stress early enough.

For example, with the environmental sensor, you only know that the soil does not have much water, but you do not actually know if the plant needs more water. With remote sensors, they detect the change in the phenotype, or what you can see outside, and that typically happens after the stress has already taken effect. So, let's say the plant is infected. By the time you see the spore on the leaf, it has likely already spread into the soil, probably to the plant next door, and then the commercial losses cascade from there.

The idea of these sensors is much like taking a page from what we call “precision medicine”. You want to detect stress early enough and pinpoint which part of the field is actually affected so that farmers have more time to engage in what we call “phytosanitary procedures”. For example, if I know a date palm is infected but I know it early enough that the fungi have not spread to the plant next door, then I do not need to remove the entire field. I just remove that plant, burn the soil, treat it, and then my loss is one plant versus five.

I want to ask about the Ibn Rush Fellowship. For students who might be interested in these sorts of opportunities in the future, what was the process for applying for the fellowship?

The fellowship has been going for three years now. I received an email saying that a new fellowship had opened. There was a seminar about it, and the announcement was sent out to all PhD students in their third year at KAUST. I attended the seminar and got more information about the fellowship itself, how it is structured, and what the expectations are.

To apply for the fellowship, you either get nominated or apply via a portal. Since I was a student at KAUST, I had to go through the nomination route. I had been working with my professor, and he was happy working with me, so he nominated me for the fellowship.

I wrote a CV, just like applying for any job – nothing particularly different there. I also had to write what we call a research statement that included what I had done in my PhD, what I planned to do in my postdoc, and how that would improve my skill set as a researcher. What would I gain from the postdoc? Why did I choose this particular lab? Why this lab and not another one?

Before I could apply, one of the conditions was to secure a tentative acceptance from the host institution. I had met Dr. Wei Gao, Professor of Medical Engineering at Cal Tech, at a conference at KAUST. I spoke with him, and my professor also knew him, so he facilitated communication between us. I emailed him, telling him I was planning to pursue a postdoc after my PhD, explained my proposal for a project, and asked if he would be interested. Once he said yes, the process for the fellowship could continue because acceptance into Ibn Rushd was contingent on securing that first.

After that, there was an interview where I was asked about my previous work, with people trying to gauge what I knew and what I did not. Then, I waited six weeks and got the decision.

What advice would you give to students who are interested in bioengineering or pursuing sensor technology?

One of the things I wish I had known back during my bachelor's was to start lab work as early as possible. I was always under the impression that I was supposed to build technical competency before entering the lab, finish my coursework, and complete all the prerequisites before getting hands-on experience. But what I discovered through research is that you learn as you go. Research is a project-based approach. When you need something for a specific task, you are more motivated to learn it yourself, whether by trial and error or by failing in the lab.

So, I would suggest that people start looking at their respective institutions not just for the courses offered, but at what the professors are working on in their research. If you find something interesting, reach out and start early. The earlier you start, the more you will learn. Freshman year courses are generally less demanding than later ones, so there is actually more time to explore research early on rather than later. That is something I wish I had taken into consideration back then.

Who would you recommend students who are interested in a similar field or in sensor technology try to meet at KAUST?

Professor Khaled Salama is my main advisor, but I also I'm also co-advised by Professor Ikram Blilou. Professor Khaled brings the sensor and electrical side, Professor Blilou brings the plant side, and I'm in the middle. For biomedical sensors, other than Professor Khalid, there is Professor Atif Shamim. He works more on RF biomedical sensors now. He started working there very recently, but he has some exciting work. There is also Professor Nazek El-Atab. She's working on wearables specifically for wound treatment. She's relatively a new professor at KAUST, but I'm lucky to have had the experience to take one of her classes and see like some of her work before I left KAUST. I would suggest people try to work with her. But there's also Professor Sahika Inal. She also works with biomedical diagnostic sensors and develops organic electrochemical transistors with a lot of exciting applications. There's also Professor Magdy Mahfouz. He works more on molecular sensing technologies, so more on the bio side than the fabrication or electrical engineering aspect of it, but still exciting, nonetheless. There is Professor Schwingenschlögl. He works mostly on quantum dots, which can be used for optical sensing. That's another exciting area where actually a Nobel Prize was recently awarded for the person who discovered quantum dots.

I would just like to acknowledge the effort that everyone has put into establishing the KGSP, including Dr. Najah Ashry, may she rest in peace, and Dr. Yusra Safi and Dr. Venu Kas. I have been their “baby” since 2012, and they truly set me on track for all of this. Without them, I would not have known about SRSI and would not have known about KAUST.

And of course, my advisors, Professor Khaled Salama, Professor Ikram, and Professor Jurgen Kosel, the professor I worked with during my master's, have all been instrumental in mentoring me throughout this time. Without them, I would not be where I am now.