Photoinduced Formation of Electrically Conductive Thin Palladium Nanowires on DNA Scaffolds

Abstract

A photochemical method has been exploited for the very fast synthesis of electrically conductive Pd nanowires on DNA. The nanowires have an average diameter of 55-75 nm and a length of approximately 3-5 mum. Our result signifies that the DNA acts both as a reducing agent as well as nonspecific capping agent for the Pd nanowire synthesis. The current voltage (I-V) characterization indicates that the nanowires are continuous and exhibit Ohmic behavior with low contact resistance. The deposition is highly selective on DNA only. Our experiment indicates that Pd nanowires may be valuable as interconnections in nanoscale integrated circuitry, functional nanodevices and in optoelectronics.

Photoinduced Silver Nanoparticles/Nanorings on Plasmid DNA Scaffolds

“…To better understand the mechanism for the synthesis of Ag nanoparticles based on plasmid scaffolds, the UV/Vis absorption spectra at different stages of synthesis were investigated for R = 1, which means that the molar ratio of Ag I ions to the plasmid base pairs is 1 ( Figure ). The plasmid has an absorption band at ≈260 nm (curve a, Figure 1) that is consistent with the absorption band of DNA 16. It confirms that the plasmids were successfully separated from the Bacillus hosts.…”

“…Compared with other biological materials, the important properties of DNA include: 1) the double‐helix rigid chain structures give DNA more mechanical strength;9 2) the DNA backbone is composed of alternating phosphate groups and sugar molecules, which exhibit negative charge and could bind various metal cations and cationic nanoparticles through electrostatic interaction;10, 11 and 3) the DNA could self‐assemble into complex structures such as cubes and squares 12, 13. Due to these properties different noble metal nanowires, such as silver,14 platinum,15 palladium,16 and copper17 nanowires, have been synthesized by using linear DNA as template. Generally, the methods for producing DNA‐templated metallic nanowires consist of two steps: 1) metal cations absorb onto the negatively charged DNA backbone forming a DNA–metal ion complex; and 2) the absorbed metal cations are reduced to metal that covers the DNA, thus forming metallic nanowires.…”

“…This process requires a long processing time and high temperature with multiple steps 10, 18. However, recent studies suggest that the metal cations absorbed on DNA can be reduced by using an ultraviolet (UV) photoirradiation approach to synthesize metallic or semiconductor nanomaterials 16, 19. The UV photoirradiation method has several advantages over the more recent chemical reduction method.…”

Microwave Synthesis of SnWO4 Nanoassemblies on DNA Scaffold: A Novel Material for High Performance Supercapacitor and as Catalyst for Butanol Oxidation

“…The appearance of LMCT band for other metal salts are also observed earlier. [40][41][42][43] A mixture of aqueous DNA, sodium tungstate and SnCl 2 shows a small hump from 237 nm to 331 nm range with a peak maximum at 258 nm (curve d, Figure 2A). The shifting of original DNA peak (curve a, Figure 2A Figure 2B.…”

Shape-selective formation and characterization of catalytically active iridium nanoparticles

“…Our group reported earlier that hydroxylic compounds reduce Pt(IV), Au(III) ions to produce their corresponding NPs in different shapes [14,47]. Recently we also reported that deoxyribonucleic acid (DNA) having hydroxyl group on their aromatic sugar part could act as a reducing agent to produce metal nanowires [13,48]. In our present work, we assumed that the hydroxyl radical formed from the mixed solution containing alkaline 2,7-DHN facilitated the reduction of Ir(III) ions to Ir(0).…”