Lipopolysaccharide identification with functionalized polydiacetylene liposome sensors.

The outer membrane of Gram negative bacteria contains lipopolysaccharides, which are glycolipids with carbohydrate sequences that are unique for each bacterial species and serotype. In this communication, we report a method for identifying LPS from different bacteria using an electronic tongue approach. Two functionalized polydiacetylene liposomes were used as colorimetric sensors for detecting various types of LPS. These liposomes were assayed under four different experimental conditions to generate a data set of eight colorimetric responses. This data set constitutes a unique fingerprint for each analyte and permits identification of each LPS type.