Aptasensor based on specific binding induced impedance changes in nanoporous anodized alumina membranes
Monitoring electrochemical impedance changes due to aptamer/ligand binding on nanochannel surface provides an attractive sensing mechanism for chemical and biological species. We report a surface charge modulation based sensing mechanism for the detection of small molecules – amodiaquine and homoserine lactone with their respective specifically binding aptamers. The change in charge distribution due to aptamer/ligand binding modifies ionic transport across the nanochannel, results in transmembrane impedance changes proportional to the amount of target present, providing a quantitative response. A sensor reader based on an analog devices chip ADuCM355 was developed and used to monitor the nanoporous membrane's impedance changes over the desired frequency range. These results show that the combination of a low cost sensor reader and aptamer functionalized membrane will enable the development of a portable and inexpensive sensor system.
This presentation is published as Nianyu Jiang, Soma Banerjee, Marit Nilsen-Hamilton, and Pranav Shrotriya. "Aptasensor based on specific binding induced impedance changes in nanoporous anodized alumina membranes," in Chemical, Biological, Radiological, Nuclear, and Explosives (CBRNE) Sensing XXII, edited by Jason A. Guicheteau, Chris R. Howle, Proc. of SPIE 11749, 117490H (12 April 2021); DOI: 10.1117/12.2586170. Posted with permission.