Rahim Esfandyarpour received his M.Sc. and Ph.D. in Electrical Engineering from Stanford University in 2010 and 2014 respectively. Currently he is an Engineering Research Associate at Stanford Genome Technology Center, Stanford Biochemistry Department and Stanford Medical School. With a multidisciplinary background, Dr. Esfandyarpour is working with a group of scientists and engineers, working on several cutting-edge research projects in biomedical field. His research covers a broad swath of engineering disciplines, interfacing micro/nanotechnology, nanoscience and nanoelectronics, micro/nanofabrication, micro/nanoscale semiconductors device physics, NEMS and MESM, flexible and wearable technologies, with applications in health monitoring, molecular and cellular detection, and energy harnessing. Specifically, his research at Stanford University focuses on using micro/nanotechnology for biomedical applications by applying innovative engineering solutions to develop next generation technologies that address the major challenges in life science discovery and to bring accessible technology-based solutions to medicine. He has near a decade of extensive experience in development of novel biomedical platforms for variety of biological applications, essential for enabling precision medicine, including early diagnostics and effective treatment of lethal diseases such as cancer.
Dr. Esfnadyarpour has authored papers in journals including PNAS, Biotechnology & Bioengineering, Sensors & Actuators B, Biomicrofluidics and Nanotechnology. His work was highlighted in New Scientist, Yahoo News, BBC World Service, Popular Science, Gizmodo, Europa Press, Science Daily, Azonano, Engineer Online, Helthcareitnews, StanfordMedNews, Tech Times, Physics.org, Labnews and several others.
Education & Certifications
Doctor of Philosophy, Stanford University, Electrical Engineering (2014)
Master of Science, Stanford University, Electrical Engineering (2010)
Poreter Dr., Palo Alto, CA., USA
Multifunctional, inexpensive, and reusable nanoparticle-printed biochip for cell manipulation and diagnosis.
Proceedings of the National Academy of Sciences of the United States of America
2017; 114 (8): E1306-E1315
Isolation and characterization of rare cells and molecules from a heterogeneous population is of critical importance in diagnosis of common lethal diseases such as malaria, tuberculosis, HIV, and cancer. For the developing world, point-of-care (POC) diagnostics design must account for limited funds, modest public health infrastructure, and low power availability. To address these challenges, here we integrate microfluidics, electronics, and inkjet printing to build an ultra-low-cost, rapid, and miniaturized lab-on-a-chip (LOC) platform. This platform can perform label-free and rapid single-cell capture, efficient cellular manipulation, rare-cell isolation, selective analytical separation of biological species, sorting, concentration, positioning, enumeration, and characterization. The miniaturized format allows for small sample and reagent volumes. By keeping the electronics separate from microfluidic chips, the former can be reused and device lifetime is extended. Perhaps most notably, the device manufacturing is significantly less expensive, time-consuming, and complex than traditional LOC platforms, requiring only an inkjet printer rather than skilled personnel and clean-room facilities. Production only takes 20 min (vs. up to weeks) and $0.01-an unprecedented cost in clinical diagnostics. The platform works based on intrinsic physical characteristics of biomolecules (e.g., size and polarizability). We demonstrate biomedical applications and verify cell viability in our platform, whose multiplexing and integration of numerous steps and external analyses enhance its application in the clinic, including by nonspecialists. Through its massive cost reduction and usability we anticipate that our platform will enable greater access to diagnostic facilities in developed countries as well as POC diagnostics in resource-poor and developing countries.
View details for DOI 10.1073/pnas.1621318114
View details for PubMedID 28167769
Nanoelectronic three-dimensional (3D) nanotip sensing array for real-time, sensitive, label-free sequence specific detection of nucleic acids.
2016; 18 (1): 7-?
The improvements in our ability to sequence and genotype DNA have opened up numerous avenues in the understanding of human biology and medicine with various applications, especially in medical diagnostics. But the realization of a label free, real time, high-throughput and low cost biosensing platforms to detect molecular interactions with a high level of sensitivity has been yet stunted due to two factors: one, slow binding kinetics caused by the lack of probe molecules on the sensors and two, limited mass transport due to the planar structure (two-dimensional) of the current biosensors. Here we present a novel three-dimensional (3D), highly sensitive, real-time, inexpensive and label-free nanotip array as a rapid and direct platform to sequence-specific DNA screening. Our nanotip sensors are designed to have a nano sized thin film as their sensing area (~ 20 nm), sandwiched between two sensing electrodes. The tip is then conjugated to a DNA oligonucleotide complementary to the sequence of interest, which is electrochemically detected in real-time via impedance changes upon the formation of a double-stranded helix at the sensor interface. This 3D configuration is specifically designed to improve the biomolecular hit rate and the detection speed. We demonstrate that our nanotip array effectively detects oligonucleotides in a sequence-specific and highly sensitive manner, yielding concentration-dependent impedance change measurements with a target concentration as low as 10 pM and discrimination against even a single mismatch. Notably, our nanotip sensors achieve this accurate, sensitive detection without relying on signal indicators or enhancing molecules like fluorophores. It can also easily be scaled for highly multiplxed detection with up to 5000 sensors/square centimeter, and integrated into microfluidic devices. The versatile, rapid, and sensitive performance of the nanotip array makes it an excellent candidate for point-of-care diagnostics, and high-throughput DNA analysis applications.
View details for DOI 10.1007/s10544-016-0032-8
View details for PubMedID 26780442
- Surface charge sensing by altering the phase transition in VO2 JOURNAL OF APPLIED PHYSICS 2014; 116 (7)
Nanoelectronic impedance detection of target cells.
Biotechnology and bioengineering
2014; 111 (6): 1161-1169
Detection of cells is typically performed using optical fluorescence based techniques such as flow cytometry. Here we present the impedance detection of target cells using a nanoelectronic probe we have developed, which we refer to as the nanoneedle biosensor. The nanoneedle consists of a thin film conducting electrode layer at the bottom, an insulative oxide layer above, another conductive electrode layer above, and a protective oxide above. The electrical impedance is measured between the two electrode layers. Cells captured on the surface of the nanoneedle tip results in a decrease in the impedance across the sensing electrodes. The basic mechanisms behind the electrical response of cells in solution under an applied alternating electrical field stems from modulation of the relative permittivity at the interface. In this paper we discuss, the circuit model, the nanofabrication, and the testing and characterization of the sensor. We demonstrate proof of concept for detection of yeast cells with specificity. We envision the sensor presented in this paper to be combined with microfluidic pre-concentration technologies to develop low cost point-of-care diagnostic assays for the clinical setting.
View details for DOI 10.1002/bit.25171
View details for PubMedID 24338648
- Label-free Electronic Detection of Target Cells Conference on Microfluidics, BioMEMS, and Medical Microsystems XII SPIE-INT SOC OPTICAL ENGINEERING. 2014
Simulation and fabrication of a new novel 3D injectable biosensor for high throughput genomics and proteomics in a lab-on-a-chip device.
2013; 24 (46): 465301-?
Biosensors are used for the detection of biochemical molecules such as proteins and nucleic acids. Traditional techniques, such as enzyme-linked immuno-sorbent assay (ELISA), are sensitive but require several hours to yield a result and usually require the attachment of a fluorophore molecule to the target molecule. Micromachined biosensors that employ electrical detection are now being developed. Here we describe one such device, which is ultrasensitive, real-time, label free and localized. It is called the nanoneedle biosensor and shows promise to overcome some of the current limitations of biosensors. The key element of this device is a 10 nm wide annular gap at the end of the needle, which is the sensitive part of the sensor. The total diameter of the sensor is about 100 nm. Any change in the population of molecules in this gap results in a change of impedance across the gap. Single molecule detection should be possible because the sensory part of the sensor is in the range of bio-molecules of interest. To increase throughput we can flow the solution containing the target molecules over an array of such structures, each with its own integrated read-out circuitry to allow 'real-time' detection (i.e. several minutes) of label free molecules without sacrificing sensitivity. To fabricate the arrays we used electron beam lithography together with associated pattern transfer techniques. Preliminary measurements on individual needle structures in water are consistent with the design. Since the proposed sensor has a rigid nano-structure, this technology, once fully developed, could ultimately be used to directly monitor protein quantities within a single living cell, an application that would have significant utility for drug screening and studying various intracellular signaling pathways.
View details for DOI 10.1088/0957-4484/24/46/465301
View details for PubMedID 24149048
- Label-free electronic probing of nucleic acids and proteins at the nanoscale using the nanoneedle biosensor BIOMICROFLUIDICS 2013; 7 (4)
Microneedle biosensor: A method for direct label-free real time protein detection
SENSORS AND ACTUATORS B-CHEMICAL
2013; 177: 848-855
Here we present the development of an array of electrical micro-biosensors in a microfluidic channel, called microneedle biosensors. A microneedle biosensor is a real-time, label-free, direct electrical detection platform, which is capable of high sensitivity detection, measuring the change in ionic current and impedance modulation, due to the presence or reaction of biomolecules such as proteins and nucleic acids. In this study, we successfully fabricated and electrically characterized the sensors and demonstrated successful detection of target protein. In this study, we used biotinylated bovine serum albumin as the receptor and streptavidin as the target analyte.
View details for DOI 10.1016/j.snb.2012.11.064
View details for Web of Science ID 000315751000113
- Label-free electronic probing of nucleic acids and proteins at the nanoscale using the nanoneedle biosensor Biomicrofluidics 2013; 7 (4)