In the midst of the pandemic, our team prototyped a volatile organic compound (VOC) sensor that seeks to detect COVID-19 using mechanisms from our noses: olfactory proteins. In taking the concept from design to testing, a massive amount of data was compiled and produced. Protein sequences were gathered from hundreds of publications on odorant binding proteins (OBPs) and cross-referenced against protein structures in the Protein Data Bank (PDB), sensor molecules were simulated in molecular dynamics, and candidates were screened using multiple experiment methods. I built and deployed the database that tied together signature disease VOCs, protein binding affinities, and protein and peptide sequences, along with molecular dynamics experimental results. In addtion, I had also pulled seqeunces from PDB and had contributed to the literature search. We demonstrate how intelligent data management enabled and accelerated a project to tackle rapid detection of COVID-19.

Platelets aggregate at the site of injury to stop bleeding, but disruptions to hemostasis can cause bleeding or thrombosis. Studying platelet-plug area and contractile force can predict whether bleeding or thrombosis is likely to occur. Microfluidic devices, composed of polydimethylsiloxane (PDMS), are used to study these biomechanics by inducing aggregation through shear flow. As blood flows through the device, the platelets pass over a rigid block in the channel which causes platelets to activate, deflecting a flexible post within the channel. This deflection is used to calculate the platelet forces based on the material properties of the PDMS. These microfluidic devices are single use and require a fabrication process that spans multiple days. Additionally, creating duplicate silicon master molds is a laborious and expensive process that necessitates cleanroom training. I am engineering and implementing a more efficient process for the fabrication of these devices, while limiting the use of the master mold that undergoes long-term wear from repeated uses. My focus is on improving the efficiency of the initial negative mold creation process by using a different material, urethane resin, to replicate the master, which allows us to make more negatives simultaneously without needing to fabricate another silicon master. To compare the devices produced using the onyx master with the silicon master, I am running three blood experiments, each with varying levels of antibodies, on two devices fabricated by the onyx and silicon masters. The aggregation sizes and forces are being observed between each of the experiments. I expect the results to be similar within a degree of certainty, proving the onyx master is equivalent to the silicon master and can be used to increase microfluidic device production and increase the availability of platelet biomechanics studies.

Insects have superlative capabilities over contemporary robots: increased mobility, redundancy, coverage area, and can utilize different sensors. Perhaps most importantly, having reduced mass, launch costs can be exponentially lower. The goal of my research project was to create a simulation to compute the pathway/logistics of an insect robot landing on Mars, code a simulation, linearize data and arrays, and learn more about insect robots and space to investigate how to land insect-sized flying robots on Mars. I first reviewed existing information on spacecraft transiting from Earth to Mars, including the need to protect insect-sized robots from space and radiation while in transit. Of great interest would be potentially different de-orbiting and landing scenarios given a lower mass spacecraft, which is still traveling a hundred times faster than a bullet during initial deorbiting. My research speculated that simpler landing strategies like Spirit and Opportunity vs Endurance might be employed for the carrier spacecraft, and once on the surface, a carrier could deploy a small rover to act as a home base supplying power and communications to the flying insect-sized robots, greatly extending the range of the science data collection. My research captured the general characteristics of insect robotics and using a Python program I created, simulated reentry paths and maximum heating rates, which were still high as expected. My next steps would be to test different ballistic coefficients to see if a small payload direct from deorbit landing is possible. The broader implication is the potential for delivering many tiny distributed sensors on Mars to dramatically improve our understanding of the planet and at a lower cost.

Development and testing of sensors and power methods for insect-based robots is a difficult task. Due to the high cost of manufacture with regards to both training time and funds, finding a sustainable and easy-to-produce method to test sensors and power options is essential. Previously, the only option for testing new sensors and power options was using one of the robotic insects, which is risky considering their high costs. Drawing from prior results, we believe a lightweight quadcopter would be faster, easier to produce, more robust, and able to serve as a suitable replacement in sensor testing and development. My goal will be to create the world's lightest and smallest quad-rotor helicopter, “TinyQuad,” with a target mass of 1–2 g. The new helicopter I have designed will enable the testing of new sensors such as cameras and power options such as radio frequency-based charging. This design allows for testing a variety of sensors and electronics configurations very quickly, with the potential to rapidly speed up the prototyping process. I will demonstrate flight capabilities through utilizing wireless charging, and sensor-based feedback control to improve flight stability and duration. I completed calculations and design of this hardware, and anticipate seeing that the collected flight data supports the utilization of a lightweight quadcopter in insect robotics development. This will allow us to rapidly develop and refine sensors for use onboard the RoboFly robotic insect platform. Creating a working quadcopter would result in accelerated prototyping that allows for more unusual sensor and payload designs, and for further research in developing new sensors and power methods for insect robotics, smaller quadcopters, and improved design of micro aerial vehicles.

Laser-induced graphene’s (LIG) simple and rapid fabrication has led to the development of flexible sensors with various applications in wearable electronics. LIG is produced in ambient air through CO₂ laser scribing on a polyimide film. Although LIG has been incorporated into flexible chemical and strain sensors, its sensitivity to resistance changes under deformation and instability prevents it from being fully utilized as a flexible conductor. This work presents a versatile technique to increase the electrical conductivity of LIG and enhance its structural stability so that it can be used as flexible conductors in printed electronics. This is achieved by the deposition and activation of functionalized liquid metal (LM) nanoparticles on LIG traces. To overcome the repulsion of LM on LIG’s surface, the CO₂ laser’s settings are adjusted to create LIG traces with a superhydrophilic inside and superhydrophobic border. Additionally, the adhesion between the LIG and LM was improved through surface functionalization of the liquid metal droplets. Our results show the resistance of LM-LIG traces to be 3 orders of magnitude smaller than that of LIG traces. Electromechanical characterization of the LM-LIG traces demonstrate low resistance changes under large bending deformations. The combination of the liquid-phase conductor and 3D structure of graphene enables the fabrication of customizable, solder-free, flexible circuits with high mechanical stability. We demonstrate this technique with the fabrication of flexible light-dependent resistor circuits that serve as a basis for further flexible sensor and biosensor exploration.

Traditional foams are fabricated via stochastic chemical processes that yield homogeneous material properties. Foams can exhibit a wide range of material properties by varying process controls allowing them to be used in many industrial and commercial applications. Previously, additive manufacturing could only produce foam approximations in the form of traditional lattice infill. My work employs viscous thread printing (VTP) of thermoplastic polyurethane (TPU) on a fused filament fabrication (FFF) printer, exploiting the semi-viscous nature of extruded filament to coil producing a new type of printed foam. Specimens were tested under compression to determine uniformity along principal axes and behavior under strain when compared to infill patterns, such as grid and cubic. My work establishes that VTP, using elastic materials, can be used to manufacture programmable stiffness foams as a function of density, suited to a variety of needs and should be considered as an alternative to traditional foams and other printed lattice geometries.

Breast cancer has higher fatality rates in low-to-middle-income countries (LMICs) within Sub-Saharan Africa compared to more developed countries. Extensive wait times for an evaluation and lack of timely follow-up care contribute to this disparity. In LMICs, breast core needle biopsies (CNBs) are commonly taken from patients by palpation, then transferred to pathologists who manually chemically preserve, slice, and analyze the tissue, which may take weeks to months for a report. We are developing CoreView, a fast, automated, and low-cost device with the ability to assess disease status within one patient visit. The CoreView instrument accepts fresh CNBs, automatically stains tissue surfaces, and generates an optical diagnostic image. For nuclei to be imaged rapidly with high-resolution within a limited depth of focus, the CNB must be pressed against a smooth clear surface, which also maximizes the tissue surface area being analyzed. To do this, compression mechanisms were modeled in SolidWorks using a piston approach and fluidic pumps to apply positive pressure. Breast tissue has low stiffness, requiring precise, applied forces. The CNB integrity and diagnostic image quality during compression was quantitatively video monitored and studied. As a control, images of compressed porcine breast CNBs were compared to matched uncompressed tissues to determine any damage with compression, and measured improvement in diagnostic image quality. Breast CNBs are expected to withstand a maximum pressure of 1.5 psi without significant tissue deformity; however, the threshold depends on the prototype dimensions/geometry. The goal is to form high-magnification, panoramic diagnostic images along the entire length of 20 mm long CNBs with ~20x microscope objective lens within one minute using motorized stage and synchronized imaging. With a reliable design and precisely controlled compression process, CoreView allows for efficient, high-resolution tissue imaging and diagnostic analysis at the point of care, reducing health disparities through prompt breast cancer treatment.

Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) that have been engineered into three-dimensional heart tissues (EHTs) are valuable research tools for investigating debilitating genetic diseases that afflict the heart, such as Duchenne muscular dystrophy (DMD). Ensuring iPSC-CMs can be sufficiently matured to model such diseases remains a hurdle in current research, and maturational analysis techniques for iPSC-CMs are either qualitative, manual, or primarily based in two dimensions, leaving much to be desired. This poster details the creation of a suite of MATLAB image-processing scripts that can quantify the effect of three-dimensional culture and disease-causing DMD mutations on cardiomyocyte structure and maturation state. The iPSC-CMs were differentiated from stem cells, cast into EHTs, stained using immunofluorescence, and imaged using confocal microscopy. Using the scripts to analyze these 3D images of iPSC-CM stains, key maturational features of the cells can be quantified such as nuclei count; cardiomyocyte area; and sarcomere length, orientation, and z-disk width. Analyzing cardiomyocyte area can give key information on cardiomyocyte hypertrophy while examining sarcomere length, orientation, and Z-disk width can provide information on myofibril structure and organization. The suite allows analysis of these maturational features in both 2D and 3D cultures and offers a method for quantitatively assessing maturation in an automated manner. Measuring iPSC-CM maturation will also allow better comparison of existing maturational methods, such as mechanical loading, electrical stimulation, and small molecule treatment. The suite can also create graphical outputs to elegantly display data. Recent progress also includes a script that can count cell nuclei and quantify cell area. Overall, the suite will help improve maturational analysis of EHTs, and hopefully contribute to the discovery of new treatments for diseases that affect the heart. 

Hepatitis C (HCV) is a liver disease caused by the bloodborne HCV virus. When left untreated, HCV can lead to cirrhosis and liver failure. Recent developments in therapeutics present a cure for HCV; however, treatment must be received soon after infection to be effective. Thus, limited availability of HCV testing creates a barrier to treatment distribution as chronic HCV is identified through a detectable viral load. Current HCV testing involves polymerase chain reaction (PCR) testing of blood samples, requiring a central laboratory and technicians to run them. The delay between appointments, sample transportation, running PCR, and receiving results can lead to lost contact with patients, making it difficult to connect them with timely treatment. The goal of the project is to develop a rapid point-of-care assay for HCV nucleic acid testing that allows healthcare providers to diagnose chronic HCV in 30 minutes and immediately prescribe treatments. We designed and validated an isothermal nucleic acid amplification assay for detecting HCV RNA: a two-step process involving reverse transcription of HCV RNA into complementary DNA (cDNA) which is detected by recombinase polymerase amplification (RPA). RPA is an isothermal process held at 40℃ with a runtime of 15 minutes, where a fluorometer collects data from the reaction. We compared the results of our RPA detection assay to the PCR-HCV assay used by the UW Clinical Virology Lab. We tested RNA from all six major genotypes using serum samples from Harborview Liver Clinic, where we had a limit-of-detection of 25 copies per reaction. We were able to match the results of the RPA and PCR assays with 100% agreement. By developing a streamlined detection assay for HCV, we will contribute to HCV testing without the need for expensive machinery or trained technicians, increasing the testing availability to increase HCV treatment rate and decrease HCV prevalence.

The detection of bioaerosols is critical to the control of public health hazards. Improvements in detection technology enable better tracking of infectious diseases, allergens, biogenic pollutants, and biowarfare agents. Bioaerosols are typically detected through laboratory analysis on collected aerosol samples. Porous filters exist for collecting aerosols, but are bulky, which makes them unsuitable for many testing environments and results in a dilute sample due to the large collection region. We present an automated microfluidic device for the collection of bioaerosols. Our design aerodynamically focuses aerosol particles into a microwell collection region, then elutes (washes off) the contents of the well into a 10 μl volume for analysis. This method automates the elution process and results in a tenfold increase in sample concentration compared to conventional filtering, making it highly compatible with analysis methods such as spectroscopy, plaque assay, and qPCR. In preliminary experiments, we evaluated device performance by collecting non-biological test particles. We then compared the device’s collection efficiency to that of reference filters and found the efficiency to be approximately 80%. Additionally, we applied a water-soluble sacrificial layer on the microwell to reduce the elution time. To optimize the sacrificial layer, sucrose solutions of varying concentration were tested on 3D-printed microwells. The next focus is on optimizing the elution protocol to achieve peak elution efficiency in the minimum timeframe. We, the undergraduate research assistants on the team, are responsible for running experiments, analyzing data, and presenting to stakeholders. This project will ultimately provide a fast and efficient method for users to examine a room for bioaerosols, with little to no training and minimal user exposure to hazardous air. We hope that this device can be provided to a variety of beneficiaries, including healthcare providers for immunocompromised individuals, severe allergy sufferers, and virulent disease researchers.

Melusin, a chaperone protein expressed in cardiac tissue, is known to induce a protective hypertrophic response in response to chronic mechanical stress. This protective hypertrophic response prevents the progression of cardiomyopathy into heart failure. In previous work done in wild-type (WT) and melusin knockout (melKO) mice, the absence of melusin was correlated with a hypertrophic response indicative of heart failure. I plan to further investigate the biomechanical role of melusin in humans using human engineered heart tissues (EHTs) created from human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) that lack melusin and their isogenic controls. EHTs are more representative of the human heart, making them an ideal model for studying the role of melusin in humans. I hypothesize that WT EHTs subjected to different mechanical stress conditions, i.e., high afterload, will outperform the melKO EHTs. In order to measure this, I increased the stiffness of the EHT posts and measured contractile force. I have been successful in differentiating high purity WT cardiomyocytes from iPSCs, essential for creating healthy EHTs. I also differentiated the melKO iPSCs and cast both WT and melKO tissues. The EHTs were planted on a bed of silicone EHT posts that can then be stiffened to induce mechanical stress on the cells. I compared the contractile force between the WT and melKO tissues. Improving our understanding of the role of melusin in humans can lead to further research into therapies and treatments for heart failure.