Label-free Her2 detection and dissociation constant assessment in diluted human serum using a longitudinal extension mode of a piezoelectric microcantilever sensor
Autor: | Gregory P. Adams, Joseph A. Capobianco, Wan Y. Shih, Wei-Heng Shih |
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Rok vydání: | 2011 |
Předmět: |
Materials science
Metals and Alloys Analytical chemistry Condensed Matter Physics Piezoelectricity Article Titanate Surfaces Coatings and Films Electronic Optical and Magnetic Materials Dissociation constant Longitudinal mode Flexural strength Materials Chemistry Electrical and Electronic Engineering Surface plasmon resonance Instrumentation Layer (electronics) Label free |
Zdroj: | Sensors and Actuators B: Chemical. 160:349-356 |
ISSN: | 0925-4005 |
Popis: | We have investigated real-time, label-free, in-situ detection of human epidermal growth factor receptor 2 (Her2) in diluted serum using the first longitudinal extension mode of a lead zirconate-lead titanate (PZT)/glass piezoelectric microcantilever sensor (PEMS) with H3 single-chain variable fragment (scFv) immobilized on the 3-mercaptopropyltrimethoxysilane (MPS) insulation layer of the PEMS surface. We showed that with the longitudinal extension mode, the PZT/glass PEMS consisting of a 1 mm long and 127 μm thick PZT layer bonded with a 75 μm thick glass layer with a 1.8 mm long glass tip could detect Her2 at a concentration of 6-60 ng/ml (or 0.06-0.6 nM) in diluted human serum, about 100 times lower than the concentration limit obtained using the lower-frequency flexural mode of a similar PZT/glass PEMS. We further showed that with the longitudinal mode, the PZT/glass PEMS determined the equilibrium H3-Her2 dissociation constant K(d) to be 3.3±0.3 × 10(-8) M consistent with the value, 3.2±0.28 ×10(-8) M deduced by the surface plasmon resonance method (BIAcore). |
Databáze: | OpenAIRE |
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