Mohsen Ebrahimi
1,2,3, Mohammad Johari-Ahar
3,4, Hossein Hamzeiy
1,3*, Jaleh Barar
3,5 
, Omid Mashinchian
3, Yadollah Omidi
3,5* 1 Department of Toxicology and Pharmacology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
2 Students’ Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
3 Research Center for Pharmaceutical Nanotechnology, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
4 Department of Medicinal Chemistry, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
5 Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
Abstract
Introduction:
Electrochemical impedance spectroscopy (EIS) is a simple and highly
sensitive technique that can be used for evaluation of the
aptamer-target interaction even in a label-free approach. Methods:
To pursue the effectiveness of EIS, in the current study, the folding
properties of specific aptamer for methamphetamine (METH) (i.e.,
aptaMETH) were evaluated in the presence of METH and amphetamine (Amph).
Folded and unfolded aptaMETH was mounted on the gold electrode surface
and the electron charge transfer was measured by EIS. Results: The Ret
of methamphetamine-aptaMETH was significantly increased in comparison
with other folding conditions, indicating specific detection of METH by
aptaMETH. Conclusion: Based on these findings,
methamphetamine-aptaMETH on the gold electrode surface displayed the
most interfacial electrode resistance and thus the most folding
situation. This clearly indicates that the aptaMETH can profoundly and
specifically pinpoint METH; as a result we suggest utilization of this
methodology for fast and cost-effective identification of METH.