The performance of flexible large-area organic photodiodes has advanced to the point that they can now offer advantages over conventional silicon photodiode technology, particularly for applications such as biomedical imaging and biometric monitoring that require detecting low levels of light across large areas.
The low-noise, solution-processed, flexible organic devices offer the ability to use arbitrarily shaped, large-area photodiodes to replace complex arrays that would be required with conventional silicon photodiodes, which can be expensive to scale up for large-area applications. The organic devices provide performance comparable to that of rigid silicon photodiodes in the visible light spectrum — except in response time.
“What we have achieved is the first demonstration that these devices, produced from solution at low temperatures, can detect as little as a few hundred thousand photons of visible light every second, similar to the magnitude of light reaching our eye from a single star in a dark sky,” said Canek Fuentes-Hernandez, principal research scientist in the School of Electrical and Computer Engineering at the Georgia Institute of Technology. “The ability to coat these materials onto large-area substrates with arbitrary shapes means that flexible organic photodiodes now offer some clear advantages over state-of-the-art silicon photodiodes in applications requiring response times in the range of tens of microseconds.”
Tissue interstitial fluid (ISF) surrounds cells and is an underutilized source of biomarkers that complements conventional sources such as blood and urine. However, ISF has received limited attention due largely to lack of simple collection methods. Here, we developed a minimally invasive, microneedle-based method to sample ISF from human skin that was well tolerated by participants. Using a microneedle patch to create an array of micropores in skin coupled with mild suction, we sampled ISF from 21 human participants and identified clinically relevant and sometimes distinct biomarkers in ISF when compared to companion plasma samples based on mass spectrometry analysis. Many biomarkers used in research and current clinical practice were common to ISF and plasma. Because ISF does not clot, these biomarkers could be continuously monitored in ISF similar to current continuous glucose monitors but without requiring an indwelling subcutaneous sensor. Biomarkers distinct to ISF included molecules associated with systemic and dermatological physiology, as well as exogenous compounds from environmental exposures. We also determined that pharmacokinetics of caffeine in healthy adults and pharmacodynamics of glucose in children and young adults with diabetes were similar in ISF and plasma. Overall, these studies provide a minimally invasive method to sample dermal ISF using microneedles and demonstrate human ISF as a source of biomarkers that may enable research and translation for future clinical applications. "
Like tiny hairs waving together, cilia are microscopic organelles found throughout nature. In your nose and ears, their metachronal beating helps trap dirt and debris. In the reproductive system, they help the ovum progress through the body and assist the movement of sperm. Given how important they are to the biological world, researchers have wondered if they could reproduce them artificially to assist in microscale motions in a variety of applications.
That is where a team of Georgia Tech researchers, which includes Professor Alexander Alexeev,Professor Peter Hesketh, and recent Ph.D. graduate Srinivas Hanasoge, comes in. The group has successfully engineered synthetic biomimetic cilia, and developed a mechanism for manipulating them using magnetic fields in a way that mimics their natural motion. Their results were recently published in ACS Applied Materials & Interfaces in an article titled “Metachronal Actuation of Microscale Magnetic Artificial Cilia.”
Researchers have developed a potential new treatment for the eye disease glaucoma that could replace daily eye drops and surgery with a twice-a-year injection to control the buildup of pressure in the eye. The researchers envision the injection being done as an office procedure that could be part of regular patient visits.
The possible treatment, which could become the first non-drug, non-surgical, long-acting therapy for glaucoma, uses the injection of a natural and biodegradable material to create a viscous hydrogel -- a water-absorbing crosslinked polymer structure -- that opens an alternate pathway for excess fluid to leave the eye.
"The holy grail for glaucoma is an efficient way to lower the pressure that doesn't rely on the patient putting drops in their eyes every day, doesn't require a complicated surgery, has minimal side effects, and has a good safety profile," said Ross Ethier, professor and Georgia Research Alliance Lawrence L. Gellerstedt Jr. Eminent Scholar in Bioengineering in the Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University. "I am excited about this technique, which could be a game-changer for the treatment of glaucoma."
Kevin Martin, who was the associate director of the Microelectronics Research Center (MiRC) for many years, passed away on June 28, 2020 in Columbus, Ohio. He retired from Georgia Tech in 2016.
Martin began working at Georgia Tech in 1987, and he served as the associate director of the MiRC before it was absorbed into the Institute for Electronics and Nanotechnology. Martin was a graduate of The Ohio State University, where he received his bachelor’s and doctoral degrees in physics. He completed postdoctoral research at the Francis Bitter Magnet Laboratory at MIT and at the University of Oregon.
Martin was a jack of many trades, contributing to several research efforts and adding value to a variety of diverse research groups, especially in the early years of the MiRC when professional research staff members were sparse. He was an expert in low temperature electronic transport measurements, and he was the original researcher to develop photomask capabilities on campus.
Martin was a key player in the acquisition and operation of Georgia Tech’s first electron beam lithography tools that resulted in Georgia Tech being thrust into the top universities in the world for nanoscale science and devices. In his closing years at Georgia Tech, he also contributed to many multi-group efforts for gigascale integration and packaging.
Martin was very involved during the early days of the Institut Lafayette project, which is based at the Georgia Tech-Lorraine campus in France. He was instrumental in the design of the clean room and the choice of equipment.
Martin will leave a lasting mark, and his sense of humor and generosity will be missed by his colleagues. He was very involved with Habitat for Humanity, where he volunteered very often. That same generosity was apparent from the interactions Martin had with users of the MiRC — he was always willing to help.
This paper presents the theory of eigenmode operation of Coriolis vibratory gyroscopes and its implementation on a thin-film piezoelectric gyroscope. It is shown analytically that the modal alignment of resonant gyroscopes can be achieved by applying a rotation transformation to the actuation and sensing directions regardless of the transduction mechanism. This technique is especially suitable for mode matching of piezoelectric gyroscopes, obviating the need for narrow capacitive gaps or DC polarization voltages. Gyroscopic operation of a 3.15 MHz AlN-on-Si annulus resonator that utilizes a pair of high-Q degenerate in-plane vibration modes is demonstrated. The piezoelectric gyroscope shows a mode-matched operation bandwidth of ~250 Hz, which is one of the largest open-loop bandwidth values reported for a mode-matched MEMS gyroscope, a small motional resistance of ~1300 Ω owing to efficient piezoelectric transduction, and a scale factor of 1.57 nA/°/s for operation at atmospheric pressure, which greatly relaxes packaging requirements. Eigenmode operation results in an ~35 dB reduction in the quadrature error at the resonance frequency. The measured angle random walk of the device is 0.86°/√h with a bias instability of 125°/h limited by the excess noise of the discrete electronics.
Yeo Lab
Wireless, continuous monitoring of daily stress and management practice via soft bioelectronics", H Kim, YS Kim, M Mahmood, S Kwon, F Epps, YS Rim, WH Yeo*, Biosensors and Bioelectronics, 173, 112764, 2021
"Recent advances in graphene-based nanobiosensors for salivary biomarker detection", R Goldoni, M Farronato, ST Connelly, GM Tartaglia, WH Yeo*, Biosensors and Bioelectronics, 171, 112723, 2021
Jinwoo Kim and a team of researchers from the Georgia Tech School of Electrical and Computer Engineering (ECE) won a best paper award at the 38th IEEE International Conference on Computer Design. The conference was held October 18-21, 2020 in a virtual format.
Joining him in receiving this award are his coauthors Chaitanya Krishna Chekuri, Nael Mizanur Rahman, Majid Ahadi Dolatsara, and Hakki Torun, who are all ECE Ph.D. students, and ECE Professors Madhavan Swaminathan, Saibal Mukhopadhyay, and Sung Kyu Lim. Kim is advised by Lim, Chekuri and Rahman are advised by Mukhopadhyay, and Dolatsara and Torun are advised by Swaminathan.
Brian Crafton, Samuel Spetalnick, and Gauthaman Murali and their faculty advisors won the Best Paper Award at this year's IFIP/IEEE International Conference on Very Large Scale Integration (VLSI SoC 2020). The conference was held October 5-7 in a virtual format.
Crafton, Spetalnick, and Murali are all Ph.D. students in the Georgia Tech School of Electrical and Computer Engineering (ECE). Crafton and Spetalnick are advised by ECE Professor Arijit Raychowdhury, and Murali is advised by ECE Professor Sung-Kyu Lim. ECE Assistant Professor Tushar Krishna also joins Raychowdhury, Lim, and their students as co-authors on the paper. .
Cleanroom Corner
The Georgia Tech MicroFab JetLab II table-top ink-jet microdispensing and printing platform, located in the Georgia Tech Biocleanroom, is useful for a wide variety of applications. Typical inks include polymers, adhesives, metallic nanoparticles, and biological materials, including diagnostic reagents, proteins, and DNA.
As a non-contact printing process, the accuracy of ink-jet dispensing is not affected by how the fluid wets a substrate, and the fluid source cannot be contaminated by materials on the substrate. In addition, the ability to free-fly fluid droplets allows the fluid to be dispensed into and onto non-planar and complex structural features.
For more information, please contact us: Linda Tian, Biocleanroom Engineer, linda.tian@ien.gatech.edu, 404-385-0151 HOLIDAY HOURS
The IEN Cleanrooms and the IEN-IMat Materials Characterization Facility will be open 24-7 during the Holiday Break. Please note that there will be limited staff assistance during the break.
IEN Center Focus: Georgia Tech 3D Systems Packaging Research Center (PRC@GT)
The 3D Systems Packaging Research Center (PRC) at the Georgia Institute of Technology is a graduated NSF Engineering Research Center focusing on advanced packaging and system integration leading to System on Package (SoP) technologies. The center conducts research and education in all aspects of packaging that includes design, materials, process, assembly, thermal management, and integration driven by applications, which include broad areas such as high-performance computing, artificial intelligence, automotive, broad band wireless, and space. The PRC team consists of 26 faculty from four schools, 11 research/administrative staff, 40+ graduate students, many undergraduate students, and several visiting engineers. This is enabled through collaboration with 33 industry/govt. labs and 8 universities and support from the GT EVPRs Office.
The Biomedical Engineering and Imaging Institute (BMEII) at the Icahn School of Medicine at Mount Sinai presents | Lucy G. Moses Lecture in Medical Imaging and Bioengineering
Thursday, December 17, 2020 | 9am-10am EST
Zoom Meeting ID: 818 6849 4265 | Passcode: 339301
Smart and Connected Soft Bioelectronics for Advancing Human Healthcare and Human-Machine Interfaces
W. Hong Yeo, Ph.D. | Assistant Professor; George W. Woodruff School of Mechanical Engineering, Wallace H. Coulter Department of Biomedical Engineering & Director of the IEN Center for Human-Centric Interfaces and Engineering, Georgia Institute of Technology Call for Papers: Virtual VOLTRON Meeting 2021 | Hosted by GTRI & the AFRL
23-24 February 2021
GTRI and AFRL invite you to present your work at the 2nd (virtual) VOLTRON meeting on 23-24 February 2021
We aim to bridge the gap between laboratory-based experiments and spectrally resolved observations of resident space objects with the intent of determining the limits, practicality, and exploitability of color photometry and spectroscopy as an SDA tool
Topics include
Laboratory-based materials measurements
Modeling of the reflective properties of spacecraft
On-sky spectral or photometric observations of resident space objects
Important Dates:
Jan. 15, 2021: Abstracts (500 words max) submissions due to elena.plis@gtri.gatech.edu and ryan.hoffmann@us.af.mil
Feb 5, 2021: Provide a pre-record 15 min presentation and submit to elena.plis@gtri.gatech.edu
Questions? Reach out to any of the below program organizers.
Elena Plis (Georgia Tech Research Institute, elena.plis@gtri.gatech.edu)
Ryan Hoffmann (AFRL Space Vehicles Directorate, ryan.hoffmann@us.af.mil)
Daniel Engelhart (Assurance Technology Corporation, daniel.engelhart.ctr@us.af.mil)
Are you interested in making a clinical impact with your research? The Georgia Clinical & Translation Science Alliance (Georgia CTSA) offers highly competitive (funded) programs of formal coursework, in a hybrid format, coupled with mentored clinical research experiences for trainees at Georgia CTSA partners (Emory, Georgia Tech, Morehouse School of Medicine, and University of Georgia).
These programs are designed for PhD students, postdocs, and junior faculty. In particular, for PhD candidates and Postdoctoral scholars a TL1 (T32-like) grant opportunity is outlined online: http://www.gactsa.org/training/tl1/index.html
Our mailing address is:
Institute for Electronics and Nanotechnology
Georgia Institute for Technology
Marcus Nanotechnology Building
345 Ferst Drive | Atlanta GA | 30332