Abstract: Metabolism of a living sample reveals a lot of information, such as its health condition, the environment (high pH or low pH) where it is incubated, etc. A simple example of this is oxygen consumption rate of a biological sample since oxygen serves as the final electron acceptor in the oxidative phosphorylation of ADP to ATP. At the same time, the amount of pH change can provide better insight into cellular metabolic processes. This is especially important to human oocyte in IVF since it is proven in some literature that oxygen consumption is a quality marker for competence conditioned by ovarian stimulation regimens. Well plates are widely used for sample collection and sample preparation in metabolism monitoring experiment, and a multi-well plate allows user to prepare samples under different treatments. In some commercial metabolism analyzer, such as Seahorse XF, live cells are seeded in a multi-well plate, and the machine performs measurement directly with a well plate loaded.
So far, the commercial platforms relying on fluorescence intensity measurement can only measure one or two of metabolites with a large quantity of the cells. The goal of the proposed device aims to develop a well plate-like platform providing simultaneous measurement of multiple analytes from multiple wells. In my research, the proposed device is a label-free system through electrochemical methods, and it is potentially able to measure up to 6 different metabolites, e.g., glucose, hydrogen peroxide, oxygen, pH, lactate, glutamine, simultaneously each with a high resolution. The system is capable of handling a single cell, such as an oocyte (120 µm), to a small biological sample, such as a small piece of mouse lung tissue (10 mm). Part of the proposed device has been experimentally tested and validated with bovine oocytes, equine oocytes, human oocytes, mouse cardiac muscle mitochondria, and so on. In order to realize the multi-sensing feature, the custom-designed circuit board has a signal bus connected to all six read channels each with a control signal, and the current board has components allowing measurement for up to 6 wells at the same time. This device is fully modularized, and it can be expanded to a higher well number, such as 24 or more. The presented device has a 12-bit ADC with a 1.4 nA read channel input-referred noise integrated up to 50 Hz, which is equivalent to an SNR value of 30 dB. A custom-designed software is developed to communicate between the user and the instrument board, and it is able to display the measured data in real-time. The preliminary data collected with this device show the same trend as the data collected with the commercial fluorescence metabolism analyzer as well as the system developed by a previous member of our lab.

Adviser: Tom Chen
Co-Adviser: N/A
Non-ECE Member: Adam Chicco, BMS
Member 3: Kevin Lear, ECE
Addional Members: Jesse Wilson, ECE; Elaine Carnevale, BMS

Publications:
[1] Obeidat, Y.M., Cheng, M.-H., Catandi, G., Carnevale, E., Chicco, A.J. and Chen, T.W., 2019. Design of a multi-sensor platform for integrating extracellular acidification rate with multi-metabolite flux measurement for small biological samples. Biosensors and Bioelectronics, 133, pp.39-47.

[2] Cheng, M.-H., Chicco, A.J., Ball, D. and Chen, T.W., 2022. Analysis of Mitochondrial Oxygen Consumption and Hydrogen Peroxide Release from Cardiac Mitochondria Using Electrochemical Multi-Sensors. Sensors and Actuators B: Chemical, 360.

Program of Study:
CM 505
CM 580A1
ECE 581B1
ECE 581B2
ECE 581B3
ECE 581B4
BIOM 581B5
STAT 511A