Electrochemical and optical aptamer-based sensors for detection of tetracyclines

Aptasensors are promising biosensors with prominent recognition capabilities. They have fascinated a lot of attention among scholars, due to the excellent characteristics of aptamers in combination with the use of nanostructures and new interface materials. The high sensitivity and selectivity of such platforms provide a promising view in food analysis. The uncontrolled usage of antibiotics, such as tetracyclines (TCs), results in the accumulation of antibiotics in food products. The traditional analytical method for detection of antimicrobial residues in food products is liquid chromatography coupled to mass spectrometric detection. Today, simple, sensitive and rapid schemes are needed for an on-site screening analysis. However, the routine techniques for TCs detection are not designed for this purpose. This review summarizes electrochemical and optical tetracycline aptasensors in food and buffer samples with focusing on modern methods and recent advances on aptamer-based tetracycline detection methods. Here, we discussed several optical and electrochemical transduction systems and their principles in aptasensor-based tetracycline detection for the first time and we focused on modern methods and recent advances. Although an optical biosensor will always have the advantage of being easier to operate with inexpensive instrument, but electrochemical aptasensors offer higher sensitivity, repeatability and accuracy. Finally, we address current challenges and future directions.