Methods and kits for the detection of DNA

The present invention is related to methods and kits for the detection of deoxyribonucleic acid (DNA), in particular pathogenic microbial DNA, which provide more simple and sensitive detection of DNA compared to similar methods and kits known in the art. The method comprises a) contacting the sample with a plurality of metal nanoparticles functionalised with one or more ribonucleic acid (RNA) probes; b) forming a heteroduplex between the target DNA and RNA probe on an RNA-functionalised metal nanoparticle; c) contacting the heteroduplex of target DNA and RNA probe on the RNA-functionalised metal nanoparticle with an enzyme that cleaves RNA in a DNA-RNA heteroduplex thereby releasing the target DNA; d) repeating steps (b) and (c) until all, or substantially all, of the RNA probes on the plurality of RNA-functionalised metal nanoparticles have been cleaved from the metal nanoparticles; and e) aggregating the metal nanoparticles from which all, or substantially all, of the RNA probes have been cleaved, thereby indicating the presence of the target DNA.