Sharif Digital Repository

A simple platform based on a hairpin oligonucleotide switch and multi-walled carbon nanotubes (MWCNTs) for the ultrasensitive detection of specific DNA sequences has been developed. In this approach, the π-stacking interaction of single-strand DNA-MWCNT was employed to construct an electrochemical DNA biosensor. Changes to the surface conductivity, based on the MWCNT replacement, were monitored by using the electrochemical species [Fe(CN)6]3-/4- as a redox probe. Morphological and voltammetric characterizations of the electrode surface were performed using atomic force microscopy (AFM), energy dispersive spectroscopy (EDS), cyclic voltammetry (CV), differential pulse voltammetry (DPV) and... 

Recently, graphitic carbon nitride (g-C3N4) has attracted great interest for photo(electro)chemical applications such as sensing, solar energy exploitation, photocatalysis, and hydrogen generation. This paper presents the potential application and benefits of g-C3N4 nanolayers as a green and highly efficient electrode modifier for the detection of trace lead ions in drinking water and urban dust samples. Carbon nitride nanosheets with a thickness of ∼6 A° and lateral of 100–150 nm were prepared through high-temperature polymerization of melamine followed by sonication-assisted liquid exfoliation. A glassy carbon electrode (GCE) was modified by a thin layer of g-C3N4 through drop casting and...