Synergizing Functional Nanomaterials with Aptamers Based on Electrochemical Strategies for Pesticide Detection: Current Status and Perspectives

Aptasensing of ciprofloxacin residue using graphene oxide modified with gold nanoparticles and branched polyethyleneimine

“…Aer activation of functional group of nanocomposites by NHS/EDC and upon the immobilization of the CFX aptamer on the modied electrode via EDC/NHS chemistry and HN-Au binding, an obvious decline in the currents of cathodic and anodic peak were observed (4.43 mA) owing to the creation of an insulating biological layer, which impended the electrons transfer. [10][11][12][13][14][15] Finally, when CFX was drop casted on the surface of Apt-modied electrode, the peak current also lightly declined (4.03 mA), indicating the assembly of Apt/CFX complex on interface of the electrode surface. Upon the addition of CFX molecule a conformational change was induced, Apt was folded and Apt/CFX complex has been arranged, which leads to the physical hindrance following by partially electron transfer inhibition.…”

“… 13 Therefore, the one-step analysis with label-free assays, reagent-free (in some cases), high sensitivity, and requiring a small sample volume could be realized. 14 In this point, different types of nanostructures were advanced and applied on the working electrode for enhancing aptamers coating amount. The 2D planar construction of graphene together with its large surface area and superb electrical conductivity make it an excellent nanomaterial in electrochemical sensing.…”

Electrochemical aptasensor based on the engineered core-shell MOF nanostructures for the detection of tumor antigens

“…By conjugating EC aptasensors with different metallic signal tags, it has been possible to detect different biological or chemical reactions with high sensitivity [ 122 , 123 ]. The development of metals-tagged aptamers is classified into two main categories: the application of pure metal NPs [ 124 , 125 ], and the development of a core-shell platform with integration of metal ions into MOF NPs with a highly specific surface area [ 126 ]. Relative to the former strategy, the latter one could be utilized to develop more different types of metals-tagged aptamers owing to the modification of MOFs with multiple electroactive metal ions, including Pb 2+ , Cd 2+ , Cu 2+ , and Zn 2+ [ 49 ].…”

Microfluidic Paper-Based Analytical Devices for the Determination of Food Contaminants: Developments and Applications

“…Moreover, the activity of enzymes will lead to false negative results. Therefore, this method has high requirements for sample pretreatment methods and the control of enzyme activity, resulting in the need to make further improvements. , Nowadays, immunoassay is the most commonly and widely used rapid detection methods for pesticide and veterinary drug residues by regulatory authorities. However, the immunological detection methods bear the risk of easy inactivation of antibodies, and the sensitivity of its detection to strong toxic pesticide residues also needs improvement.…”