Electrochemical Detection of Vascular Endothelial Growth Factor with Aptamer Sandwich

Abstract

We developed an electrochemical vascular endothelial growth factor (VEGF) detection system using two VEGFbinding aptamers. Sensitive detection systems of VEGF are highly required for cancer diagnosis. In this study, VEGF-A was detected using a sandwiching method with a pyrroquinoline quinone glucose dehydrogenase (PQQ-GDH)-labeled VEGF-binding aptamer and another aptamer immobilized onto a gold wire electrode. We evaluated various combinations of VEGF-binding aptamers to be employed in the process. In addition, we examined dose dependency for the electric current generated by PQQ-GDH, measured in the constructed VEGF detection system. Using this newly constructed system, we successfully detected VEGF 165 at 15 nM (M = mol dm −3 ) concentration.

Screening and Biosensor-Based Approaches for Lung Cancer Detection

“…Over the years, researchers worldwide have paid attention to developing label-free and high-sensitive biosensors for early diagnosis of diseases such as lung cancer. Table 4 lists some recently developed biosensors for lung tumor marker detection [ 166 , 167 , 168 , 169 , 170 , 171 , 172 , 173 , 174 , 175 , 176 , 177 , 178 , 179 , 180 ].…”

A New Method for the Label-Free Detection of Vascular Endothelial Growth Factor Based on DNAzymes

“…[13][14][15] Label-free DNA molecules are commercially available in various forms and commonly used in immunoassays, thereby providing a powerful tool cabinet for the choice of appropriate method for sensor design. Moreover, when compared with other fluorescent-, [16] electrochemical- [17,18] aptasensor-based methods, the current colorimetric read-out method is expected to find widespread application in high-throughput detection. Therefore, this strategy can be extended to the design of protein and DNA sensors.…”

G-quadruplex DNAzyme-based electrochemiluminescence biosensing strategy for VEGF165 detection: Combination of aptamer–target recognition and T7 exonuclease-assisted cycling signal amplification

“…4, a broad linear relationship between the differences in the ECL intensity and the logarithm of concentration of VEGF 165 in the range of 1 pM to 20 nM with a correlation coefficient (R) of 0.996, and the linear fitting equation is ΔI¼882.14-1432.2 lg [c], where ΔI is I 0 À I, c is the concentration of VEGF 165 ; this range was wider than those in previous reports (Zhao et al, 2012;Freeman et al, 2012;Kopra et al, 2014;Mita et al, 2014;Cho et al, 2012;Chen et al, 2014). Detection limit was experimentally estimated to be 0.2 pM, which was lower than that in fluorescence (Freeman et al, 2012;Kopra et al, 2014) and electrochemical method (Nonaka et al, 2012) (the detailed comparison of the analytical performance for VEGF 165 detection by using our strategy and those reported in the literature is summarized in Table 1). And this value is certainly adequate to analyze most of the VEGF-related diseases (Freeman et al, 2012).…”

“…Aptamers present many distinctive advantages, such as easy synthesis procedure, chemical modification, low production cost, and high stability in harsh biological environments, compared with antibodies (Iliuk et al, 2011). Aptamer-based strategies for VEGF detection have been incorporated with different signal transduction methods, such as fluorescence (Freeman et al, 2012;Kopra et al, 2014), surface-enhanced Raman scattering (Ko et al, 2013), and the electrochemical method (Nonaka et al, 2012).…”