Matching Items (18)
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- All Subjects: Biomedical
- All Subjects: Diabetes
- Creators: Harrington Bioengineering Program
- Creators: Spano, Mark
Description
This report outlines the current methods and instrumentation used for diabetes monitoring and detection, and evaluates the problems that these methods face. Additionally, it will present an approach to remedy these problems. The purpose of this project is to create a potentiostat that is capable of controlling a diabetes meter that monitors multiple biological markers simultaneously. Glucose is the most commonly measured biomarker for diabetes. However, it provides only a limited amount of information. In order to give the user of the meter more information about the progression of his or her disease, the concentrations of several different biological markers for diabetes may be measured using a system that operates in a similar fashion to blood glucose meters. The potentiostat provides an input voltage into the electrode sensor and receives the current from the sensor as the output. From this information, the impedance may be calculated. The concentrations of each of the biomarkers in the blood sample can then be determined. In an effort to increase sensitivity, the diabetes meter forgoes the use of amperometric i-t in favor of the electrochemical impedance spectroscopy technique. A three-electrode electrochemical sensor is used with the meter. In order to perform simultaneous and rapid testing of biomarker concentration, a single multisine input wave is generated using a hardware implementation of a summing amplifier and waveform generators.
ContributorsWu, Diane Zhang (Author) / LaBelle, Jeffrey (Thesis director) / Bakkaloglu, Bertan (Committee member) / Spano, Mark (Committee member) / Barrett, The Honors College (Contributor) / Electrical Engineering Program (Contributor)
Created2013-05
Description
Diabetes mellitus is a disease characterized by many chronic and acute conditions. With the prevalence and cost quickly increasing, we seek to improve on the current standard of care and create a rapid, label free sensor for glycated albumin (GA) index using electrochemical impedance spectroscopy (EIS). The antibody, anti-HA, was fixed to gold electrodes and a sine wave of sweeping frequencies was induced with a range of HA, GA, and GA with HA concentrations. Each frequency in the impedance sweep was analyzed for highest response and R-squared value. The frequency with both factors optimized is specific for both the antibody-antigen binding interactions with HA and GA and was determined to be 1476 Hz and 1.18 Hz respectively in purified solutions. The correlation slope between the impedance response and concentration for albumin (0 \u2014 5400 mg/dL of albumin) was determined to be 72.28 ohm/ln(mg/dL) with an R-square value of 0.89 with a 2.27 lower limit of detection. The correlation slope between the impedance response and concentration for glycated albumin (0 \u2014 108 mg/dL) was determined to be -876.96 ohm/ln(mg/dL) with an R-squared value of 0.70 with a 0.92 mg/dL lower limit of detection (LLD). The above data confirms that EIS offers a new method of GA detection by providing unique correlation with albumin as well as glycated albumin. The unique frequency response of GA and HA allows for modulation of alternating current signals so that several other markers important in the management of diabetes could be measured with a single sensor. Future work will be necessary to establish multimarker sensing on one electrode.
ContributorsEusebio, Francis Ang (Author) / LaBelle, Jeffrey (Thesis director) / Pizziconi, Vincent (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Diabetes is a growing epidemic in developing countries, specifically in rural Kenya. In addition to the high cost of glucose testing, many diabetics in Kenya do not understand the importance of testing their blood glucose, let alone the nature of the disease. This project addresses the insufficiency of educational materials regarding diabetes in rural Kenya. The resulting documents can easily be adjusted for use in other developing countries.
ContributorsBuchak, Jacqueline (Author) / Caplan, Michael (Thesis director) / Snyder, Jan (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
The action/adventure game Grad School: HGH is the final, extended version of a BME Prototyping class project in which the goal was to produce a zombie-themed game that teaches biomedical engineering concepts. The gameplay provides fast paced, exciting, and mildly addicting rooms that the player must battle and survive through, followed by an engineering puzzle that must be solved in order to advance to the next room. The objective of this project was to introduce the core concepts of BME to prospective students, rather than attempt to teach an entire BME curriculum. Based on user testing at various phases in the project, we concluded that the gameplay was engaging enough to keep most users' interest through the educational puzzles, and the potential for expanding this project to reach an even greater audience is vast.
ContributorsNitescu, George (Co-author) / Medawar, Alexandre (Co-author) / Spano, Mark (Thesis director) / LaBelle, Jeffrey (Committee member) / Guiang, Kristoffer (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Currently, the management of diabetes mellitus (DM) involves the monitoring of only blood glucose using self-monitoring blood glucose devices (SMBGs) followed by taking interventional steps, if needed. To increase the amount of information that diabetics can have to base DM care decisions off of, the development of an insulin biosensor is explored. Such a biosensor incorporates electrochemical impedance spectroscopy (EIS) to ensure an extremely sensitive platform. Additionally, anti-insulin antibody was immobilized onto the surface of a gold disk working electrode to ensure a highly specific sensing platform as well. EIS measurements were completed with a 5mV sine wave that was swept through the frequency spectrum of 100 kHz to 1 Hz on concentrations of insulin ranging from 0 pM to 100 μM. The frequency at which the interaction between insulin and its antibody was optimized was determined by finding out at which frequency the R2 and slope of the impedance-concentration plot were best. This frequency, otherwise known as the optimal binding frequency, was determined to be 459 Hz. Three separate electrodes were developed and the impedance data for each concentration measured at 459 Hz was averaged and plotted against the LOG (pM insulin) to construct the calibration curve. The response was calculated to be 263.64 ohms/LOG(pM insulin) with an R2 value of 0.89. Additionally, the average RSD was determined to be 19.24% and the LLD was calculated to be 8.47 pM, which is well below the physiological normal range. These results highlight the potential success of developing commercial point-of-care insulin biosensors or multi-marker devices operating with integrated insulin detection.
ContributorsDecke, Zachary William (Author) / LaBelle, Jeffrey (Thesis director) / Pizziconi, Vincent (Committee member) / Cook, Curtiss (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2013-05
Description
The purpose of this study, which was done in conjunction with the Arizona Heart Foundation, was to evaluate whether pyridoxine accelerates ulcer wound healing in diabetic patients with ulcers in the lower extremities. In this study, 100 mg of pyridoxine per day was given to patients in the experimental group (while they receive normal wound treatment) while patients in the control group received normal treatment of wounds without the pyridoxine. Over time, wound healing was evaluated by photographing and then measuring the size of patients' ulcer wounds on the photographs. Results from the experimental group were compared with those of the control group to evaluate the efficacy of the pyridoxine treatment. In addition, comparisons of the healing rates were made with respect to whether the patients smoked, had hypertension or hypotension, and the patients' body mass indexes. It has been found that there was no statistically significant difference in the mean healing rates between the control groups and experimental groups. In addition, it has been found that smoking, BMI and blood pressure did not have a statistically appreciable effect on the difference in mean healing rates between the control and experimental groups. This is evidence that pyridoxine did not have a statistically significant effect on wound healing rates.
ContributorsHaupt, Shawn Anthony (Author) / Caplan, Michael (Thesis director) / Pauken, Christine (Committee member) / Pagan, Pedro (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2013-05
Description
Volume depletion can lead to migraines, dizziness, and significant decreases in a subject's ability to physically perform. A major cause of volume depletion is dehydration, or loss in fluids due to an imbalance in fluid intake to fluid excretion. Because proper levels of hydration are necessary in order to maintain both short and long term health, the ability to monitor hydration levels is growing in clinical demand. Although devices capable of monitoring hydration level exist, these devices are expensive, invasive, or inaccurate and do not offer a continuous mode of measurement. The ideal hydration monitor for consumer use needs to be characterized by its portability, affordability, and accuracy. Also, this device would need to be noninvasive and offer continuous hydration monitoring in order to accurately assess fluctuations in hydration data throughout a specified time period. One particular method for hydration monitoring that fits the majority of these criteria is known as bioelectric impedance analysis (BIA). Although current devices using BIA do not provide acceptable levels of accuracy, portability, or continuity in data collection, BIA could potentially be modified to fit many, if not all, desired customer specifications. The analysis presented here assesses the viability of using BIA as a new standard in hydration level measurement. The analysis uses data collected from 22 subjects using an existing device that employs BIA. A regression derived for estimating TBW based on the parameters of age, weight, height, sex, and impedance is presented. Using impedance data collected for each subject, a regression was also derived for estimating impedance based on the factors of age, weight, height, and sex. The derived regression was then used to calculate a new impedance value for each subject, and these new impedance values were used to estimate TBW. Through a paired-t test between the TBW values derived by using the direct measurements versus the calculated measurements of impedance, the two samples were found to be comparable. Considerations for BIA as a noninvasive measurement of hydration are discussed.
ContributorsTenorio, Jorge Antonio (Author) / LaBelle, Jeffrey (Thesis director) / Pizziconi, Vincent (Committee member) / Spano, Mark (Committee member) / Barrett, The Honors College (Contributor) / W. P. Carey School of Business (Contributor) / Harrington Bioengineering Program (Contributor)
Created2013-05
Description
Abstract: The delivery of a drug or gene payload inside an individual neuron has been highly sought after and studied as a means of treating a large variety of neurological diseases and disorders such as cancer and Alzheimer’s. Current technology for these applications remains imperfect particularly with respect to matters of precision and cell viability. Thus, the use of MEMS (micro electro mechanical systems) based systems have become more prevalent in order to conduct these processes with higher precision and automation. Penetrating these specific cells while also maintaining their structural integrity during the process, remain as two major hurdles still being explored today. Electrical stimulation has been used to drive the delivery of a payload at the microscale but to do so with a voltage that keeps the neuron viable is imperative. In order to find a means for optimizing the voltage and ejection of the payload while maintaining cell viability, the goal of this project is to explore the use of pulsed waveforms for driving the delivery. In doing so, lower to moderate voltage amplitudes may potentially be used while also avoiding hydrolysis of the cell. This study was done by ejecting dye dextran from glass micropipettes with an agar and artificial seawater well using both DC and pulsed waveforms. Successful ejection of the payload was achieved and confirmed using fluorescent microscopy. While the methods used for this voltage based delivery require further optimization, the successful ejection utilizing pulsed voltages suggest that this may lead to an improved technique for MEMS based delivery of payloads into single cells in the future.
ContributorsStamm, Steven Jeffrey (Author) / Muthuswamy, Jitendran (Thesis director) / Sridharan, Arati (Committee member) / Harrington Bioengineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Piloerection (known as goosebumps) is mediated by activation of alpha-adrenergic receptors within the sympathetic branch of the autonomic nervous system. The study of piloerection is important in multiple fields, from emotion studies to nervous system pathology. This makes piloerection particularly relevant to emotions research. Despite wide-ranging applications, current methods for measuring piloerection are laborious and qualitative. The goal of this study is to build a wearable piloerection sensor through the use of straight-line lasers and photoresistors. The study analyzed methods of detecting and measuring goosebumps, and applied the method of laser scattering as a detection method. This device was designed and tested against a population of seven Arizona State University students. Goosebumps were elicited through conditions of cold, and video clips meant to elicit emotions of awe and sadness. Piloerection was then quantified through two controls of self-identification and camera recording, as well as the new detection method. These were then compared together, and it was found that subjective methods of determining goosebumps did not correlate well with objective measurements, but that the two objective measurements correlated well with one another. This shows that the technique of laser scattering can be used to detect goosebumps and further developments on this new detection method will be made. Moreover, the presence of uncorrelated subjective measurements further shows the need for an objective measurement of piloerection, while also bringing into question other factors that may be confused with the feeling of piloerection, such as chills or shivers. This study further reaffirmed previous studies showing a positive correlation between intense emotions.
ContributorsHemesath, Angela (Author) / Muthuswamy, Jitendran (Thesis director) / Shiota, Michelle (Lani) (Committee member) / Harrington Bioengineering Program (Contributor, Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Homelessness is a pervasive in American society. The causes of homelessness are complex, but health and homelessness are inextricably linked. Student-run free clinics care for underserved populations, including people experiencing homelessness, but they have multiple agendas—to provide care but also to give students hands-on experience. It is plausible that these two agendas may compete and give patients sub-par quality of care.
This study examines patient care in the SHOW free clinic in Phoenix, Arizona, which serves adults experiencing homelessness. This study asks two questions: First, do clinicians in Phoenix’s SHOW free clinic discuss with patients how to pay for and where to access follow-up services and medications? Second, how do the backgrounds of patients, measured by scales based on the Gelberg-Anderson behavioral model for vulnerable populations, correlate with patient outcomes, including number of unmet needs in clinic, patient satisfaction with care, and patient perceived health status? To answer these questions, structured surveys were administered to SHOW clinic patients at the end of their visits. Results were analyzed using Pearson’s correlations and odds ratios. 21 patients completed the survey over four weeks in February-March 2017. We did not identify any statistically significant correlations between predisposing factors such as severity/duration of homelessness, mental health history, ethnicity, or LGBTQ status and quality of care outcomes. Twenty nine percent of surveyed patients reported having one or more unmet needs following their SHOW clinic visit suggesting an important area for future research. The results from this study indicate that measuring unmet needs is a feasible alternative to patient satisfaction surveys for assessing quality of care in student-run free clinics for homeless populations.
This study examines patient care in the SHOW free clinic in Phoenix, Arizona, which serves adults experiencing homelessness. This study asks two questions: First, do clinicians in Phoenix’s SHOW free clinic discuss with patients how to pay for and where to access follow-up services and medications? Second, how do the backgrounds of patients, measured by scales based on the Gelberg-Anderson behavioral model for vulnerable populations, correlate with patient outcomes, including number of unmet needs in clinic, patient satisfaction with care, and patient perceived health status? To answer these questions, structured surveys were administered to SHOW clinic patients at the end of their visits. Results were analyzed using Pearson’s correlations and odds ratios. 21 patients completed the survey over four weeks in February-March 2017. We did not identify any statistically significant correlations between predisposing factors such as severity/duration of homelessness, mental health history, ethnicity, or LGBTQ status and quality of care outcomes. Twenty nine percent of surveyed patients reported having one or more unmet needs following their SHOW clinic visit suggesting an important area for future research. The results from this study indicate that measuring unmet needs is a feasible alternative to patient satisfaction surveys for assessing quality of care in student-run free clinics for homeless populations.
ContributorsWilson, Ethan Sinead (Author) / Jehn, Megan (Thesis director) / Harrell, Susan (Committee member) / School of Human Evolution and Social Change (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05