Abstract

Binary Lipid vesicle-Gold Nanoparticle on Gold Surface for Enhanced DNA and Protein Sensing

Divya Karutha Pandian, Research Scholar, Alagappa University

Binary lipid mixture of cationic lipid and zwitterionic lipid were used to tether on thiol monolayers such as Cysteamine hydrochloride (Cyst), 3-Mercaptopropionic acid (MPA), 11- Mercaptoundecanoic acid (MUDA) and 11-amino- 1-undecane thiol (AUT) monolayers in the absence and presence of gold nanoparticle for enhanced sensor stability and sensitivity for DNA and protein sensing. The presence of AuNP and zwitterionic lipid decreases the electrostatic interaction between cationic lipid and self-assembled monolayer. TEM images and AFM images endorse the presence of an array like semi circled and well separated vesicles with variable sizes. The effective coordination between lipids and gold nanoparticle are evidenced using Dynamic Light Scattering (DLS) and Fourier Transform Infrared spectroscopy (FTIR). The DNA hybridization sensing carried out in presence of the ferri/ferrocyanide results in the lowest DNA detection limit of 1?10 -14 M with a linearity range of 1?10 -13 to 1?10 -9 M. Likewise, the protein streptavidin is detected upto 1 ng ml -1 with a linear range 100 ng to 1 µg.