| Author: | Liu, Yuan |
| Title: | Point-of-care biosensing platform based on photoluminescent nanoparticles and microfluidic biochip for in-vitro biomarkers diagnostics |
| Advisors: | Hao, Jianhua (AP) |
| Degree: | Ph.D. |
| Year: | 2025 |
| Department: | Department of Applied Physics |
| Pages: | xix, 153 pages : color illustrations |
| Language: | English |
| Abstract: | Identifying biomarkers with high sensitivity and portability is of significant importance for screening and managing diseases that threaten human health. Compared with some commercial biomarkers diagnostic methods, the developed point-of-care biosensing platform possesses various advantages involving easy to operation, low cost, portable, and rapid, which implies potential application in the future. In terms of the biomarker of Nucleocapsid protein (N protein) detection, the point-of-care biosensing platform based on UCNPs and microfluidic biochip was designed and fabricated. The UCNPs were successfully synthesized and used as the luminescent agent. The microfluidic biochip was utilized as the detection chamber of the portable virus diagnostic platform, which possesses luminescence enhancement properties with a maximum of over 100-fold than the cuvette samples. Moreover, the cleanable property of microfluidic biochip also implied promised application for the virus diagnosis area. Compared with the typical commercial rapid test strips for virus detection, this biosensing platform exhibited a higher sensitivity of around 1.12 pg/ml for N protein detection. In addition, the clinical samples are also investigated and manifested that the designed point-of-care virus detection platform possessed better diagnostic sensitivity compared with the normal commercial LFA rapid test strips. For the carcinoembryonic antigen (CEA) tumor marker diagnostics, the developed point-of-care biosensing platform based on QDs luminescence and microfluidic biochip with machine vision algorithm analysis was well-designed and manufactured. The core-shell QDs nanoparticles with excellent luminescent properties were employed for the labelling indicator in the immunoassay. The microfluidic biochip with excellent separation and cleanable abilities was utilized as assisted chamber for the biosensing platform, which illustrated a sensitivity of around 0.021 ng/mL. The Python-based machine vision algorithm was developed for this point-of-care CEA detection. Furthermore, for the research of practical application, the designed intelligent biosensing platform exhibited remarkable cut-off value comparing with some common-used commercial LFA test strips. In addition, for the relevant biomarker of α-Syn protein for emerging neurodegenerative diseases (NDDs), a PDMS-based hydrophobic biochip was designed and manufactured. Specifically, the AutoCAD software was used to create the PDMS-based biochip's pattern while considering pertinent hydrophobic equations and associated studies. The SERS functionalized biochip was successfully designed and manufactured from the related morphology investigations of various view of SEM images using the PDMS demolding and UV irradiation photoreduction techniques. Moreover, the related optical pictures further demonstrate the great hydrophobic performance for fabricated biochip. In the end, the associated Raman spectra suggest that a well-designed and manufactured point-of-care biochip can be used to differentiate the various α-Syn protein structures, suggesting enormous promise for the detection of NDDs in the future. |
| Rights: | All rights reserved |
| Access: | open access |
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