(4fb) Low-Cost Medical Devices for Drug Delivery and Fluids in Nature

Research Interests: In recent decades, drug delivery research has surged forward, especially with the advent of new-generation vaccines and therapeutics. Despite these advancements, conventional drug delivery techniques still face limitations, highlighting the need for a simple, effective, and safe one-step solution for transdermal drug delivery. My lab aims to address this gap using my expertise in needle-free drug delivery and low-cost medical devices. We will investigate the underlying mechanisms of intracellular nucleic acid delivery to boost immune responses through carrier-free innovative drug delivery techniques. Fluid dynamics play a crucial role in the functioning of biosensors and drug injectors, which extract bodily fluids and deliver drugs across the skin. By combining laboratory experiments, theoretical analysis, and computational modeling, we aim to improve the performance of these medical devices by understanding and optimizing their operational mechanisms. Current in vitro and ex vivo skin models suffer from issues of availability, cost, and reproducibility. Transparent poroviscoelastic hydrogels present a promising solution for evaluating drug delivery devices, drug testing, and studying bacterial growth in 3D matrices. Enhancing the mechanical properties and poroviscoelasticity of these models will enable us to focus on improving designs of drug delivery devices. Another research front of my lab will focus on organismal interactions with fluids. Bioinspiration and biomimicry have significantly advanced material design and engineering. Understanding of phenomena behind organismal functions in nature can be applied to robotics and engineering. In summary, our laboratory will investigate fluid dynamics in medicine and biology to pioneer low-cost, efficient medical devices for drug delivery and skin modeling, in addition to curiosity-driven research in organismal interactions with fluids.

Teaching interests: With a Chemical Engineering background, I have interest in teaching core courses like Fluid Mechanics, Transport Phenomena, Chemical Engineering Thermodynamics, and Mathematical Methods in Chemical Engineering, as well as in developing courses on Drug Delivery, and Soft Matter. My teaching approach combines context, applications, history, and storytelling, using lectures, active-learning exercises, media, and web tools for instant feedback and improved learning outcomes.

Biosketch: I am an Eckert Postdoc Fellow at the labs of Saad Bhamla and Mark Prausnitz at Georgia Institute of Technology. My research expertise lies in medical devices, fluid dynamics, complex fluids, and drug delivery. During postdoc, I have focused on developing low-cost hardware for intracellular delivery of nucleic acids. Addressing the limitations of lipid nanoparticle (LNP) to deliver mRNA, we developed the ePatch, a $1 handheld electroporator for naked mRNA delivery. The ePatch showed comparable in vivo expression to conventional methods without the need of carriers and demonstrated excellent safety and minimal pain in human trials. I am exploring its potential in gene therapy and vaccine development, including enhancing red blood cell production and immune responses to mRNA-based SARS-CoV-2 vaccine. I have also dedicated significant research efforts on studying the fluid dynamics in organismal interactions with fluids. My work includes investigating how semi-aquatic organisms walk on water, how termites spit viscoelastic jets through their micron-scale nozzles and the physics of filter-feeding in flamingoes. In this research, I have discovered unique fluid dynamics phenomena which can be utilized in designing efficient microrobots and nozzles. My doctoral research (Texas Tech University, PI: Jeremy Marston) focused on understanding the hydrodynamics of drug delivery via needle-free jet injectors. This research improved the delivery efficiency of jet injectors from ~65% to ~95% in ex vivo skin models and revealed the role of fluid properties and rheology on delivery efficiency and jetting dynamics. I also explored feasibility of novel techniques such as laser and spark-induced jetting in drug delivery. Additionally, I studied the fluid dynamics of drug delivery via tattooing and to the front of the eye via eye drops, minimizing drug wastage by making droplet spreading faster than the blink reflex. My research also included studying mechanisms involved in fluid-driven cracking processes like hydraulic fracturing, and ancient disease diagnostic techniques based on interfacial spreading of fluids. In summary, I have successfully addressed diverse research challenges across pharmaceutics, bioengineering, and chemical engineering.

Key Publications:

• Lu, Chao-yi^∗, Rohilla, Pankaj^∗, Felner, Eric I., Byagathvalli, Gaurav, Azizoglu, Erkan, Bhamla, Saad and Prausnitz, Mark R. Tolerability of a piezoelectric microneedle electroporator in human subjects. Bioengineering and Translational Medicine. e1066 (2024)
• Lawal, Idera, Rohilla, Pankaj, and Marston, Jeremy O. Visualization of drug delivery via tattooing: effect of needle reciprocating frequency and fluid properties, Journal of Visualization, 1-9 (2022).
• Rohilla, Pankaj, Lawal, I., Blanc, A.L., O’Brien, V., Weeks, C., Tran, W., Rane, Y.S., Khusnatdinov, E., and Marston, J.O. Loading effects on the performance of needle-free jet injections in different skin models, Journal of Drug Delivery Science and Technology 60, 102043 (2020).
• Rohilla, Pankaj, Rane, Y.S., Lawal, I., Blanc, A.L., Davis, J., Thomas, J.B., Weeks, C., Tran, W., Fisher, P., Broderick, K.E., Simmons, J.A. and Marston J.O., Characterization of jets for impulsively started needle-free jet injectors: Influence of fluid properties, Journal of Drug Delivery Science and Technology 53, 101167 (2019).
• Rohilla, Pankaj, and O’Neil, Johnathan, Bose, Chandan, Ortega-Jimenez, Victor, Choi, Daehyun, Bhamla, Saad. Epineuston vortex recapture enhances thrust in tiny water skaters, BioRxiv. (2024).
• Challita, Ellio J., Rohilla, Pankaj, and Bhamla, M. Saad. Fluid ejections in nature, Annual Review of Chemical and Biomolecular Engineering, 15 (2024).
• Rohilla, Pankaj, and Marston, Jeremy O. Feasibility of laser induced jets in needle-free jet
  injections, International Journal of Pharmaceutics 589, 119714 (2020).
• Deodhar, S., Rohilla, Pankaj, Manivannan, M., Thampi, S.P., and Basavaraj, M.G. Robust method to determine critical micelle concentration via spreading oil drops on surfactant solutions, Langmuir 36 (28): 8100-8110 (2020).