Automation and Instrumentation for the D4 Platform

Microfluidics: We are actively developing microfluidic versions of the D4-POCT to decrease the user intervention to  simply adding a single drop of blood and a few drops of buffer to carry out the D4 assay. The automated chip would passively complete the assay, wash the surface, and then dry without intervention for a true one-step test. This implementation would reduce the risk of user error, and limit exposure to hazardous waste. To achieve this goal this goal, we are developing microfluidic chips for biological fluid handling and a portable detector for assay readout.

 

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Handheld Optical Detector: To make the D4 fully point-of-care, we are developing an analyte-sensitive, user-friendly, portable, economical, and rapid fluorescent detector— the D4Scope. The current prototype (the “Einstein”) matches the fluorescent sensitivity of clinical-grade scanners, for a fraction of the cost. The Einstein is constructed from a Raspberry Pi, off-the-shelf optical components, and custom CAD 3D printed parts. A custom Python-based touchscreen user interface runs on the device’s touchscreen, which fully automates the D4 detection step. Within 5 seconds of a button press, the D4 can be scanned and biomarker concentration is reported. Further development is going towards both hardware and software optimization for user friendliness and reproducibility.

 

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Publications

Vahabi, Hamed, Jason Liu, Yifan Dai, Daniel Y. Joh, Rhett Britton, Jacob Heggestad, David Kinnamon, Satyam Rajput, and Ashutosh Chilkoti. “A gravity-driven droplet fluidic point-of-care test.” Device 1, no. 1 (July 2023): 100009. https://doi.org/10.1016/j.device.2023.100009.

Burrow, Damon T., Jacob T. Heggestad, David S. Kinnamon, and Ashutosh Chilkoti. “Engineering Innovative Interfaces for Point-of-Care Diagnostics.” Current Opinion in Colloid & Interface Science, June 2023, 101718. https://doi.org/10.1016/j.cocis.2023.101718.

Kinnamon, David S., Jacob T. Heggestad, Jason Liu, and Ashutosh Chilkoti. “Technologies for Frugal and Sensitive Point-of-Care Immunoassays.” Annual Review of Analytical Chemistry (Palo Alto, Calif.) 15, no. 1 (June 2022): 123–49. https://doi.org/10.1146/annurev-anchem-061020-123817.

Joh, Daniel Y., Jacob T. Heggestad, Shengwei Zhang, Gray R. Anderson, Jayanta Bhattacharyya, Suzanne E. Wardell, Simone A. Wall, et al. “Cellphone enabled point-of-care assessment of breast tumor cytology and molecular HER2 expression from fine-needle aspirates.” NPJ Breast Cancer 7, no. 1 (July 2, 2021): 85. https://doi.org/10.1038/s41523-021-00290-0.

Patents

J. Liu and Chilkoti, A. , “DEVICES AND METHODS FOR IMAGING MICROARRAY CHIPS”, U.S. Patent 17/607,7612022.