Complementary response of In2O3 nanowires and carbon nanotubes to low-density lipoprotein chemical gating

Abstract

In 2 O 3 nanowire and carbon nanotube transistors were used to study the chemical gating effect of low-density lipoproteins (LDL). The adsorption of LDL on these two different surfaces was investigated, which revealed a tenfold more LDL particle adsorption on carbon nanotubes than on In2O3 nanowires because of hydrophobic/hydrophilic interactions. The conductance of field-effect transistors based on nanowires and nanotubes showed complementary response after the adsorption of LDL: while In2O3 nanowire transistors exhibited higher conductance accompanied by a negative shift of the threshold voltage, the nanotube transistors showed lower conductance after the exposure. This is attributed to the complementary doping type of In2O3 nanowires (n type) and carbon nanotubes (p type).