Day 1- Wednesday- Flight to Casper
Wednesday morning began the long trek to Casper consisting of 3 plane rides. 11 hours later, I arrived in Casper, where there were some nice bird-eye’s views of the Casper Mountains on the descent.
I was thrilled to receive the notification this week that I was selected to receive funding for the Engineering Learning Initiatives Grant here at Cornell for the summer of 2016! This will allow me to devote myself full time to working on electrorotation of algae cells this summer. The project is a new area of application very different from the original cancer cell subjects of our electrorotation studies. Our results could give us an interesting view into the optimizing the efficiency of algal biofuels in the future. I am looking forward to the new experience!
I recently presented my work on characterizing the electrical properties of cancer cells at the AES (Electrophoresis Society) Annual Meeting, which was a part of the AiCHE Annual Meeting. One electrokinetic technique (dielectrophoresis) may be used to enhance capture of cancer cells from a suspension containing contaminating blood cells. This technique, however, relies on a good model of the electrical properties of cancer cells. It is possible that these electrical properties of cancer cells change when cells gain resistance to chemotherapy or when they’re exposed to or deprived of certain stimuli in circulation. I used electrorotation (a technique related to dielectrophoresis), which revealed changes of pancreatic cancer cell lines’ electrical properties in response to such stimuli.
At this meeting, I also had the opportunity to meet leaders in the field of electrokinetics. In particular, I enjoyed presentations from and/or conversations with Dr. Amy Herr, Dr. Fatima Labeed, Dr. Mike Hughes, Dr. Adrienne Minerick, Dr. Nathan Swami, Dr. Lisa Flanagan, Dr. Ben Hawkins, and many other investigators and students.
My work on “Enhancing sensitivity and specificity in rare cell capture microdevices with dielectrophoresis” was recently published in Biomicrofluidics, with co-authors Charlie Huang and Brian Kirby. This paper describes numerical simulations that identify microfluidic obstacle array geometries where dielectrophoersis (DEP) can be combined with immunocapture to increase the capture of target rare cells, such as circulating tumor cells (CTCs), while simultaneously repelling contaminating cells. These simulations build on our previous efforts that have shown that cancer cells exhibit a different DEP response than healthy blood cells, and lay the groundwork for the experimental study of hybrid DEP–immunocapture obstacle array microdevices.
Separately, I have also reported on “A transfer function approach for predicting rare cell capture microdevice performance” in Biomedical Microdevices. This work describes a numerical technique that extends our previously-reported computational fluid dynamics (CFD) simulations of rare cell transport and capture in microfluidic devices into larger, more complex geometries. This transfer function approach matches the full CFD simulation within 1.34% at a 74-fold reduction in computational costs, and the transfer function’s predictions for lateral displacement within complex reversing geometries were validated experimentally using particle tracking and polystyrene microspheres in a GEDI device.
Earlier this year, I joined the technical staff of the MIT Lincoln Laboratory, working in the Engineering Division‘s Structural and Thermal-Fluids Engineering Group. I’m splitting my time between research and engineering efforts, and am enjoying the exposure to new fields and exciting applications, while continuing to build on my work in microfluidics.
My paper entitled “Characterization of microfluidic shear-dependent epithelial cell adhesion molecule immunocapture and enrichment of pancreatic cancer cells from blood cells with dielectrophoresis” was recently published in the journal Biomicrofluidics. This paper describes my work on characterizing shear-dependent EpCAM immunocapture of pancreatic cancer cells enhanced by positive dielectrophoresis (DEP) and nonspecific adhesion of blood cells reduced by negative DEP. We evaluated capture probability as a function of shear stress, cell surface chemistry, and normal force using a capture probability model, and demonstrated that DEP can enhance immunocapture of cancer cells with lower EpCAM expression and that immunocapture purity can potentially be improved by repelling blood cells with negative DEP. This work informs the design of future hybrid DEP-immunocapture devices with increased CTC capture purity, which will facilitate subsequent functional and genetic analyses to elucidate cancer progression and develop more effective treatment options.
Huang C, Smith JP, Saha TM, Rhim AD, Kirby BJ. “Characterization of microfluidic shear-dependent epithelial cell adhesion molecule immunocapture and enrichment of pancreatic cancer cells from blood cells with dielectrophoresis,” Biomicrofluidics, 8(4): 044107, 2014. DOI
I also recently started as a Postdoctoral Research Staff Member at Lawrence Livermore National Laboratory in Livermore, CA in the Center for Bioengineering, Micro and Nano Technology Section of the Materials Engineering Division. I will be working on an acoustofluidics cell/particle separation project as well as a microfluidic nanoparticle synthesis project. I am very much enjoying NorCal weather and having weekends free!
Godla recently presented a talk entitled “Using Rare Cell Capture to Understand Metastasis” at the 13th International Summer School on Biocomplexity, Biodesign, and Bioinnovation in Istanbul, Turkey. The presentation highlighted recent work using GEDI immunocapture to isolate circulating tumor cells (CTCs) from a metastatic pancreatic cancer mouse model, with the goal of comparing genetic mutations in these CTCs with mutations found in the primary tumor and metastases. More information on the Summer School can be found here.
I recently traveled to Newport, RI to attend the Bioanalytical Sensors Gordon Research Seminar (at which I presented a talk and a poster), and the Bioanalytical Sensors Gordon Research Conference (at which I presented a poster). My presentations focused on my recent work on measuring the electrical properties of cancer cells and observing how these properties change in response to stimuli. Such measurements are important for robust, optimal operation of dielectrophoresis-based cell capture devices.