Authors: Y-P. Kim, S. Park, E. Oh, Y-H. Oh, H-S. Kim
Affilation: KAIST, Korea
Pages: 244 - 247
Keywords: energy transfer, quantum dot, gold nanoparticle, glycosylation
Protein glycosylation is one of the most essential processes in the living systems, and often is a major target for developing therapeutics and diagnosis. We have developed a chip-based energy transfer system between quantum dot (QDs) and gold nanoparticles (AuNPs) to specifically detect protein glycosylation. Our system relies on modulations in the energy transfer between the nanoparticles on a surface; that is, the photoluminescence (PL) of lectin-coated QD (energy donor) immobilized on a glass slide is quenched by carbohydrate-coated AuNPs (energy acceptor), and the presence of the glycoprotein causes the increase of the PL of QD. As a model system, Concanavalin A-coated QD (ConA-QD) and dextran-coated AuNP (Dex-AuNP) were employed to detect the mannosylated proteins, showing that the linear signals were observed for the concentration as well as the number of glycan moiety of the glycoprotein. Compared to the conventional energy-transfer systems, our approach resulted in high energy transfer efficiency, even in the range of distance exceeding ~10 nm. In addition, the AuNPs can be used as a common energy acceptor in conjunction with different donor QDs. This chip-based format also enabled more reliable analyses with no aggregation of nanoparticles as well as with much smaller reaction volume. Our system will be promising for the development of therapeutics and diagnostics of glycoproteins with high selectivity and sensitivity in a multiplexed and high-throughput manner.