TY - JOUR
T1 - SPAD aptasensor for the detection of circulating protein biomarkers
AU - Pasquardini, Laura
AU - Pancheri, Lucio
AU - Potrich, Cristina
AU - Ferri, Alessandro
AU - Piemonte, Claudio
AU - Lunelli, Lorenzo
AU - Napione, Lucia
AU - Comunanza, Valentina
AU - Alvaro, Maria
AU - Vanzetti, Lia
AU - Bussolino, Federico
AU - Pederzolli, Cecilia
PY - 2015/6/5
Y1 - 2015/6/5
N2 - The need for decentralized clinical tests together with the concept of time and cost saving are pushing the development of portable, miniaturized, compact biosensors with diagnostic and prognostic purpose. Here, we propose an innovative detection system based on a Single Photon Avalanche Diode (SPAD) with high sensitivity and low noise, crucial features for an efficient chemiluminescence biosensor. The SPAD detector, having 60. μm diameter, has a Photon Detection Efficiency higher than 55% at 425. nm and a Dark Count Rate lower than 100. Hz at room temperature. Our design allows a good optical coupling efficiency between sample and detector. A specific biofunctional surface was implemented taking advantage of aptamers, short DNA sequences having high selectivity and affinity toward their targets. We successfully detected physiological levels of Vascular Endothelial Growth Factor (VEGF), a circulating protein biomarker highly correlated with cancer. The SPAD aptasensor showed a Limit of Detection (LoD) in the pM range, stability (up to 42 days) and re-usability (up to seven cycles). This compact biosensor is therefore a promising step toward the actual use of portable microdevices in diagnostics.
AB - The need for decentralized clinical tests together with the concept of time and cost saving are pushing the development of portable, miniaturized, compact biosensors with diagnostic and prognostic purpose. Here, we propose an innovative detection system based on a Single Photon Avalanche Diode (SPAD) with high sensitivity and low noise, crucial features for an efficient chemiluminescence biosensor. The SPAD detector, having 60. μm diameter, has a Photon Detection Efficiency higher than 55% at 425. nm and a Dark Count Rate lower than 100. Hz at room temperature. Our design allows a good optical coupling efficiency between sample and detector. A specific biofunctional surface was implemented taking advantage of aptamers, short DNA sequences having high selectivity and affinity toward their targets. We successfully detected physiological levels of Vascular Endothelial Growth Factor (VEGF), a circulating protein biomarker highly correlated with cancer. The SPAD aptasensor showed a Limit of Detection (LoD) in the pM range, stability (up to 42 days) and re-usability (up to seven cycles). This compact biosensor is therefore a promising step toward the actual use of portable microdevices in diagnostics.
KW - Aptamer
KW - Chemiluminescence
KW - SPAD
KW - VEGF
UR - http://www.scopus.com/inward/record.url?scp=84921720496&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84921720496&partnerID=8YFLogxK
U2 - 10.1016/j.bios.2015.01.042
DO - 10.1016/j.bios.2015.01.042
M3 - Article
C2 - 25636022
AN - SCOPUS:84921720496
VL - 68
SP - 500
EP - 507
JO - Biosensors and Bioelectronics
JF - Biosensors and Bioelectronics
SN - 0956-5663
ER -