CAREER: Design of Colorimetric and Chiroptical Sensors for Illegal Substances

Doane University, Crete NE

Investigators

Abstract

With the support of the Organic and Macromolecular Chemistry Program at the National Science Foundation, Professor Andrea Holmes of Doane College in Crete, Nebraska will develop new macromolecular color sensors for the detection of abused narcotics. Professor Holmes, a post-doctoral research associate, and an undergraduate research team will work primarily toward the design of sensors for chiral drugs such as cocaine and methamphetamine by 1) developing molecular color sensors from aptamers (oligonucleotide-based binders) that change color in the presence of small quantities of drugs, 2) testing the utilization of circular dichroism (CD) spectroscopy as a technique for discriminating between the enantiomers of chiral drugs that are often abused, and 3) developing a solid matrix that allows the new chemical sensors to be attached to a solid support for actual use outside the laboratory in a field test product. The organic synthetic and analytical techniques used include solid-phase synthesis, the determination of binding constants by UV/Vis and fluorescence spectroscopy, combinatorial 96-well plate methods, circular dichroism spectroscopy, and MALDI-TOF or Electrospray Ionization mass spectrometry. The exploration of incorporating aptamer sensors into sol-gels reflects the creative symbiosis of solution phase and solid phase chemistry. Results from this CAREER award will provide an improved understanding of achiral host and chiral drug interactions and the development of a library of aptamer-dye structures that are sensitive and specific to abused narcotics. The work may eventually lead to new drug-detection tools for forensic scientists and others. The PI will integrate the research into undergraduate courses in organic chemistry in classes enrolling predominantly rural students, many of whom intend to become science teachers. Students participating on the research team will provide classroom activities for local middle school students and return to their own high schools as science mentors.