Effects of gold nanoparticle on surface and electrical characterizations of functionalized Interdigitated Electrode (IDE) for biomolecules detection

Abstract

Usually biomolecules such as proteins, RNAs, aptamers and other nucleic acids are detected using conventional lab methods. Nowadays, biosensors are emerging as an alternative way for diagnosis purposes. Linearity, high throughput detection and lower response time are some of the reasons biosensors are ideal mediums for detection of biomolecules. Among all other biosensors, electrochemical biosensors have picked up the interest of many researches due to their sensitivity and selectivity. Interdigitated Electrode (IDE) is classified under electrochemical biosensor and is known for its specificity. On the other hand, metal nanoparticles have been under intensive investigation due to their potential as conductive layer on biosensor surface. Gold nanoparticle, in particular, is an active catalyst for biosensing applications. As a present work, an IDE was successfully designed and fabricated composed of microelectrodes joined together with a series of finger-like structures prior to functionalization with gold nanoparticles on its surface. Later, electrical measurements as well as surface characterizations were recorded for both bare IDE and gold nanoparticle-functionalized IDE for comparison purposes via current-voltage measurements and Scanning Electron Microscope respectively.