Characterization of a self-assembled monolayer of thiol on a gold surface and the fabrication of a biosensor chip based on surface plasmon resonance for detecting anti-GAD antibody

Planar lipid bilayers on sensor chip surfaces have become useful tools to study membrane bound processes by surface plasmon resonance spectroscopy. We immobilized phospholipids on sensor chips by different approaches. First, a self-assembled monolayer of octadecylmercaptan was formed on a blank gold surface and subsequent addition of phospholipids led to formation of a heterobilayer. Second, a self-assembled monolayer of mercaptoundecanoic acid was formed on a gold surface, the carboxy groups of mercaptoundecanoic acid were activated and covalently linked to phosphatidylethanolamine. Addition of phospholipids then led to a bilayer with phosphatidylethanolamine as the lower leaflet. Third, a hydrophobic sensor chip (L1, BIAcore) was used as a binding matrix for phospholipids. These lipid surfaces were tested, whether they are suitable to study proteinamembrane interactions. As biological test system we used the Ca2+-myristoyl-switch of the neuronal Ca2+-binding protein recoverin. All three surfaces were sufficiently stable to monitor the Ca2+-dependent binding of recoverin to membranes.

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Grating-Coupled Surface-Plasmon-Resonance Biosensor Discs with a C-Type Fluidic Channel for Monitoring Growth of Self-Assembled Monolayer

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.284-287.2069 ◽

2013 ◽

Vol 284-287 ◽

pp. 2069-2074 ◽

Cited By ~ 3

Author(s):

Jenq Nan Yih ◽

Kuo Chi Chiu ◽

Sheng Yu Chou ◽

Chih Ming Lin ◽

Yung Sung Lan ◽

...

Keyword(s):

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Gold Surface ◽

Measuring System ◽

Response Curves ◽

Self Assembled Monolayer ◽

Fluidic Channel ◽

Promising Tool ◽

Self Assembled

In this paper, we present a grating-coupled surface plasmon resonance (SPR) biosensor with a c-type fluidic channel on a grating disc. For obtaining the kinetic information of molecular interaction, we combined a c-type fluidic channel on disc to drive testing solution forward by gravity via turning the grating disc. The disc biosensor can react with probe molecules on the different sensing surfaces in the following time. The repeatability testing shows the resolution of angle of the measuring system was enhanced by threefold comparing to that without the automation improvement. In order to identify the accuracy of angle changes of SPR due to the chemical reaction on surface, experiment for monitoring a growth self-assembled monolayer (SAM) immobilized on gold surface was performed. The measured response curves show that the saturation time of the SAM formation, which thickness is smaller than 2 nm, is roughly 5 hours when 1 mM MHDA growing on gold at room temperature. The demonstration reveals that the disc biosensor with c-type fluidic channels can be a promising tool for a kinetic analysis of bimolecular interaction without any external fluid pumping systems.

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