Cardiovascular Marker Proteins Detection in the Blood Serum Using an LSPR Chip Based on Au Nanobipyramid

Abstract

The localized surface plasmon resonance (LSPR) based technology allows the fabrication of inexpensive biosensors with very simple design for the detection of diseases. In the present work, we systematically fabricated an LSPR sensor chip using Au nanobipyramids (Au NBPs). Au NBPs with longitudinal LSPR band in the near-IR region (~900nm) exhibiting higher refractive index (RI) sensitivity are used for the sensor chip fabrication. The immobilized Au NBPs on a silanized glass coverslip were chemically modified using 11-mercaptoundecanoic acid (11-MUA) and Octanethiol monolayer, followed by activation using EDC-NHS chemistry for the immobilization of the protein molecules. For cardiovascular marker protein detection, monoclonal antibodies were immobilized on the sensor chip, and the marker proteins were detected from the blood serum obtained from the patients. Cardiovascular marker proteins N-terminal pro-B-type natriuretic peptide and cardiac troponin T (CTnT) were successfully detected on the fabricated LSPR sensor chip.