TY - JOUR
T1 - Resonant gravimetric immunosensing based on capacitive micromachined ultrasound transducers
AU - Viržonis, Darius
AU - Vanagas, Gailius
AU - Ramanavičiene, Almira
AU - Makaraviciute, Asta
AU - Barauskas, Dovydas
AU - Ramanavičius, Arũnas
AU - Wen, Weijia
AU - Kodzius, Rimantas
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This research is funded by a grant (No. MIP-059/2012) from the Research Council of Lithuania.
PY - 2014/4/8
Y1 - 2014/4/8
N2 - High-frequency (40 MHz) and low-frequency (7 MHz) capacitive micromachined ultrasound transducers (CMUT) were fabricated and tested for use in gravimetric detection of biomolecules. The low-frequency CMUT sensors have a gold-coated surface, while the high-frequency sensors have a silicon nitride surface. Both surfaces were functionalized with bovine leukemia virus antigen gp51 acting as the antigen. On addition of an a specific antibody labeled with horseradish peroxidase (HRP), the antigen/antibody complex is formed on the surface and quantified by HRP-catalyzed oxidation of tetramethylbenzidine. It has been found that a considerably smaller quantity of immuno complex is formed on the high frequency sensor surface. In parallel, the loading of the surface of the CMUT was determined via resonance frequency and electromechanical resistance readings. Following the formation of the immuno complexes, the resonance frequencies of the low-frequency and high-frequency sensors decrease by up to 420 and 440 kHz, respectively. Finite element analysis reveals that the loading of the (gold-coated) low frequency sensors is several times larger than that on high frequency sensors. The formation of the protein film with pronounced elasticity and stress on the gold surface case is discussed. We also discuss the adoption of this method for the detection of DNA using a hybridization assay following polymerase chain reaction.
AB - High-frequency (40 MHz) and low-frequency (7 MHz) capacitive micromachined ultrasound transducers (CMUT) were fabricated and tested for use in gravimetric detection of biomolecules. The low-frequency CMUT sensors have a gold-coated surface, while the high-frequency sensors have a silicon nitride surface. Both surfaces were functionalized with bovine leukemia virus antigen gp51 acting as the antigen. On addition of an a specific antibody labeled with horseradish peroxidase (HRP), the antigen/antibody complex is formed on the surface and quantified by HRP-catalyzed oxidation of tetramethylbenzidine. It has been found that a considerably smaller quantity of immuno complex is formed on the high frequency sensor surface. In parallel, the loading of the surface of the CMUT was determined via resonance frequency and electromechanical resistance readings. Following the formation of the immuno complexes, the resonance frequencies of the low-frequency and high-frequency sensors decrease by up to 420 and 440 kHz, respectively. Finite element analysis reveals that the loading of the (gold-coated) low frequency sensors is several times larger than that on high frequency sensors. The formation of the protein film with pronounced elasticity and stress on the gold surface case is discussed. We also discuss the adoption of this method for the detection of DNA using a hybridization assay following polymerase chain reaction.
UR - http://hdl.handle.net/10754/563494
UR - http://link.springer.com/10.1007/s00604-014-1244-3
UR - http://www.scopus.com/inward/record.url?scp=84907860557&partnerID=8YFLogxK
U2 - 10.1007/s00604-014-1244-3
DO - 10.1007/s00604-014-1244-3
M3 - Article
SN - 0026-3672
VL - 181
SP - 1749
EP - 1757
JO - Microchimica Acta
JF - Microchimica Acta
IS - 13-14
ER -