A Sensitive capacitive immunosensor for direct detection of human heart fatty acid-binding protein (h-FABP)

作者：Mihailescu Carmen Marinela^*; Stan Dana; Iosub Rodica; Moldovan Carmen; Savin Mihaela

来源：Talanta, 2015, 132: 37-43.

DOI：10.1016/j.talanta.2014.08.067

• Self-assembled monolayer
• Cardiac marker
• Acute myocardial infarction
• Capacitive immunosensor
• h-FABP

The fabrication of a capacitive interdigitated immunosensor (CID) based on a mixed self-assembled monolayer (mSAM) film for the direct detection of heart fatty-add binding protein (h-FABP) without any labeling is described. The capacitance changes of mSAMs vs. homogenous ordered self-assembled monolayers (hSAMs) on gold work electrodes/covalently bonded antibodies/buffered medium are utilized for monitoring the specific antibody-antigen interaction. Capacitance measurements in the absence and presence of Faradaic currents were performed. The electrochemical properties of mixed monolayers were compared with those of a pure monolayer of 11-mercaptoundecanoic acid (MUA) self-assembled on gold surfaces. Taking into account the stability of the studied monolayers during the electrochemical experiments with the Faradaic process, the best SAM functionalization method was used for developing a sensitive capacitive immunosensor with a non-Faradaic process for direct immune detection of human h-FABP. Under the optimized conditions, the proposed mixed self-assembled monolayer (mSAM(1)) on gold electrode exhibited good insulating properties such as a capacitive behavior when detecting h-FABP from human serum in the range of 98 pg ml(-1)-100 ng ml(-1), with a detection limit of 0.836 ng ml(-1) comparative with a homogenous self-assembled monolayer (hSAM).

• 出版日期2015-1-15