DNAzyme biosensors for detection of toxic metal ions

INOR 731

Hee-kyung Kim, hkim11@uiuc.edu, Juewen Liu, jliu2@uiuc.edu, Daryl P. Wernette, dwernett@uiuc.edu, Debapriya Mazumdar, dmazumda@uiuc.edu, Geng Lu, and Yi Lu, yi-lu@uiuc.edu. Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Matthews Ave, Urbana, IL 61801
A new class of fluorescent and colorimetric biosensors has been developed for simple and fast detection of trace contaminants. A DNAzyme with high specificity for Pb2+ has been isolated using an in vitro selection method and converted to sensors by coupling with flurophore/quencher or gold nanoparticles. The fluorescent biosensors are highly sensitive with a detection limit of 2 ppb for Pb2+, below that of EPA drinking water limit of 15 ppb. The immobilization of the sensor on gold coated surfaces has made possible dry storage and regeneration for long term use. The detection of Pb2+ in water with various hardness has been achieved using a portable fluorometer, showing on-site and real time detection is possible. The detection of Pb2+ in leaded paint has been demonstrated using the colorimetric sensor below the federal threshold of 1 mg/cm2. Our approach is general enough so that sensors for other metal ions such as Cd2+, Hg2+, Co2+ and U6+ have been or are being obtained.
 

Materials: Applications
7:00 PM-10:00 PM, Tuesday, 12 September 2006 Moscone Center -- Hall D, Poster

Division of Inorganic Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006