Comparison of a carboxylated terthiophene surface with carboxymethylated dextran layer for surface plasmon resonance detection of progesterone.
Functionalization of a gold surface is usually accomplished by covalent binding via self-assembled monolayers (SAMs) on the gold surface, followed by attachment of flexible polymeric linker layers such as dextran hydrogels. However, these techniques require multiple steps and also have nonspecific interactions and steric problems. In this study, a self-assembled carboxylated terthiophene monolayer was formed onto a gold surface to create a sensitive and stable surface plasmon resonance (SPR) biosensing system. Compared with a commercial carboxymethyl dextran chip (CM5), the terthiophene SAM surface provided more than six times more antibody-binding signals and nearly three times the SPR assay sensitivity for progesterone (P4).
The New Zealand Institute for Plant & Food Research, Sandringham, Auckland 1025, New Zealand; The University of Auckland, Auckland 1010, New Zealand.
Yijing
Y
Wang
The University of Auckland, Auckland 1010, New Zealand; MSL, Rosedale, Auckland 0632, New Zealand.
Ashton
A
Partridge
The New Zealand Institute for Plant & Food Research, Sandringham, Auckland 1025, New Zealand. Electronic address: yinqiu.wu@plantandfood.co.nz.
Yinqiu
Y
Wu
D002623:Chemistry Techniques, Analytical / Q000379:methods*; D003911:Dextrans / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D015394:Molecular Structure; D011374:Progesterone / Q000032:analysis* / Q000737:chemistry; D020349:Surface Plasmon Resonance; D013499:Surface Properties; D013876:Thiophenes / Q000737:chemistry*
D003911:Dextrans; D013876:Thiophenes; C019101:alpha-terthienyl; D011374:Progesterone; D006046:Gold; C014392:carboxymethyl dextran
Gold surface; Progesterone; Surface plasmon resonance; Terthiophene