Aptasensors sandwich design

Some works have reported the use of aptasensors based on sandwich design for the detection of different proteins, namely THR, C-reactive protein (CRP), vascular endothelial growth factor (VEGF) (Ravalli et al., 2015), mucin 1 (MUCl) (Chen etal., 2015), and PDGF (Wang et al., 2009) (Table 13.1). 

Table 13.1 Examples of electrochemical aptasensors based on sandwich design... 

Numnuam et al. (2008) reported the first potentiometric aptasensor nsing ion-selective microelectrodes for THR detection. In the sandwich design, the THR was captured by a thiolated aptamer attached to the surface of the gold electrode and the measurements were based on cadmium sulfide quantum dot (CdS-QDs) label of the secondary aptamer. The potentiometric aptasensor presented good sensitivity allowing the detection of up to 28fmol of THR in PBS buffer solutions (detection limit of 0.14 nM). 

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