In this work, we investigate the detection sensitivity of surface plasmon resonance (SPR) biosensors by engineering spatial distribution of electromagnetic near-fields for colocalization with molecular distribution. The light-matter colocalization was based on plasmonic nanolithography, the concept of which was confirmed by detecting streptavidin biotin interactions on triangular nanoaperture arrays after the structure of the aperture arrays was optimized for colocalization efficiency. The colocalization was shown to amplify optical signature significantly and thereby to achieve detection on the order of 100 streptavidin molecules with a binding capacity below 1 fg/mm2, an enhancement by more than three orders of magnitude over conventional SPR detection.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation (NRF) Grants (NRF-2012R1A4A1029061, NRF-2015R1A2A1A10052826,and NRF-2016K2A9A2A06004899). K. Chung and D.H. Kim acknowledge the financial support by the NRF of Korea Grant funded by the Korean Government (2014R1A2A1A09005656).
All Science Journal Classification (ASJC) codes
- Biomedical Engineering