Laser pulse energy conversion on sequence-specifically bound metal nanoparticles and its application for DNA manipulation

Abstract

Abstract The manipulation of DNA is a central point in modern molecular biology and thereby DNA restriction has widespread applications. Besides manipulating the DNA it is used in DNA analytics as ‘restriction analysis’. This method uses DNA digestion by sequence-specific restriction enzymes. The resulting length distribution of the digested/cut fragments is detected by gel electrophoresis. Differences in the DNA sequence result in different restriction patterns. However, a restraint of this standard method is the limitation to a small set of known restriction enzymes with fixed sequences, so that the assay cannot be adapted to every sequence of interest (such as e.g. single nucleotide polymorphisms (SNP)). In this work a scheme for DNA restriction based on laser light conversion on sequence-specifically positioned metal nanoparticles is presented. Especially gold nanoparticles are known for their interesting optical properties caused by plasmon resonance. The observed absorption is used to convert laser light pulses into heat, resulting in nanoparticle destruction. We combine this principle with DNA-modification of nanoparticles and the sequence-specific binding (hybridization) of these DNA-nanoparticle complexes along DNA molecules. Different mechanisms of light conversion were studied, and the destructive effect of laser light on the nanoparticles and DNA is demonstrated.