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ERIC Number: EJ832484
Record Type: Journal
Publication Date: 2009-Mar
Pages: 3
Abstractor: As Provided
Reference Count: 11
ISSN: ISSN-0021-9584
Polydiacetylene-Based Liposomes: An "Optical Tongue" for Bacteria Detection and Identification
West, Matthew R.; Hanks, Timothy W.; Watson, Rhett T.
Journal of Chemical Education, v86 n3 p373-375 Mar 2009
Food- and water-borne bacteria are a major health concern worldwide. Current detection methods are time-consuming and require sophisticated equipment that is not always readily available. However, new techniques based on nanotechnology are under development that will result in a new generation of sensors. In this experiment, liposomes are synthesized that consist of a bacteria-sensing structure on the outer surface and a polydiacetylene signal transducer. The sensor gives a dramatic blue-to-red color change in the presence of lipopolysaccarides (LPS) extracted from bacteria cell walls. The treatment of slightly different liposomes under multiple analysis conditions may be used to create a sensor array (an optical tongue) that is able to distinguish between LPS derived from different Gram-negative bacteria. The experiment introduces students to concepts of self-assembly, supramolecular synthesis, biosensor design, and to the basic structure of bacteria cell walls. It also readily lends itself to expansion as an investigative-learning experience through student-led modification of the liposome structure. (Contains 2 schemes and 1 figure.)
Division of Chemical Education of the American Chemical Society. Subscription Department, P.O. Box 1267, Bellmawr, NJ 08099-1267. Tel: 800-691-9846; Tel: 856-931-5825; Fax: 856-931-4115; e-mail:; Web site:
Publication Type: Journal Articles; Reports - Descriptive
Education Level: Higher Education
Audience: Teachers
Language: English
Sponsor: N/A
Authoring Institution: N/A