A Simple Colorimetric Au‐on‐Au Tip Sensor with a New Functional Nucleic Acid Probe for Food‐borne Pathogen Salmonella typhimurium

Abstract An Au‐on‐Au tip sensor is developed for the detection of Salmonella typhimurium ( Salmonella ), using a new synthetic nucleic acid probe (NAP) as a linker for the immobilization of a DNA‐conjugated Au nanoparticle (AuNP) onto a DNA‐attached thin Au layer inside a pipette tip. In the presence of Salmonella , RNase H2 from Salmonella (STH2) cleaves the NAP and the freed DNA‐conjugated AuNP can be visually detected by a paper strip. This …