Upgraded resolution and enhanced sensitivity of optical disc-based bioassays: from CD to BD

Conventional biomedical diagnosis and chemical analysis are performed by trained professionals in centralized laboratories using specialized instrumentation. Our group has been working on the development of optical disc technology-based molecular detection platforms for on-site chemical analysis and point-of-care diagnosis for the past 15 years. In particular, computer-readable assays on compact discs (CDs) have been demonstrated for the quantitation of various target analytes, such as DNA, proteins, and metal ions. In this thesis, two more advanced disc formats, digital versatile disc (DVD) and Blu-ray disc (BD) have been adapted to improve the assay resolution and detection sensitivity. The DVD assay for quantitative analysis of human chorionic gonadotropin is described first. A multiplex assay-on-a-BD system for the detection of a set of key cardiac markers is then explained in detail. Beyond a different error correction protocol, a new surface activation method has been established for the immobilization of probe molecules on the surface coating of BD-Rs. In addition to the upgraded lateral resolution, the sensitivity of the BD-based bioassays is significantly improved in comparison with those prepared on CDs and DVDs, which is comparable to the well-established enzyme-linked immunosorbent assay (ELISA).