Polyadenine-mediated Immobilization of Aptamers on a Gold Substrate for the Direct Detection of Bacterial Pathogens.
Nucleic acid aptamers have been widely used as synthetic probes for bioanalytical applications. Herein, we carried out a detailed study on the immobilization of a series of aptamers ranging from 37 to 88 bases, which are specific to either Escherichia coli (E. coli) or Staphylococcus aureus (S. aureus), on a planar gold substrate via a polyadenine-mediated immobilization method. The resultant surfaces were characterized by both surface plasmon resonance spectroscopy (SPR) and X-ray photoelectron spectroscopy. The results clearly show that the aptamer solution at a lower ionic strength gives rise to a higher lateral density of the aptamer when compared to that at a higher ionic strength. The SPR aptasensors are then employed for detecting their corresponding bacteria (i.e., E. coli and S. aureus, respectively). The data indicate that the SPR aptasensor with a higher density of aptamer exhibits a better capture of target bacteria.
['Wang|Wen-Wen|WW|', 'Han|Xiao|X|', 'Chu|Li-Qiang|LQ|']
D052157:Aptamers, Nucleotide D001483:Base Sequence D001965:Bromides D004926:Escherichia coli D006046:Gold D009994:Osmolar Concentration D011061:Poly A D017670:Sodium Compounds D013211:Staphylococcus aureus D020349:Surface Plasmon Resonance
aptamer Escherichia coli Staphylococcus aureus Surface plasmon resonance spectroscopy polyadenine