Investigation of the electrochemiluminescent reaction of fluoroquinolone antibiotics with tris(2,2'-bipyridyl)ruthenium(II)

CHED 330

Matthew Burkhead, msb38308@creighton.edu, Heeyoung Wang, wang369@creighton.edu, and Erin Gross, eringross@creighton.edu. Department of Chemistry, Creighton University, 2500 California Plaza, Omaha, NE 68178
A flow injection analysis system (FIA) was constructed to study electrochemiluminescence (ECL) reactions. This FIA consisted of a homemade flow cell with a Pt working electrode for light generation and a viewing window for collection of photons with a photomultiplier tube. The ECL of a class of antibiotics called fluoroquinolones was studied in order to determine what particular structures within the fluoroquinolones were responsible for ECL. The system was optimized for enrofloxacin (enro). The greatest light intensity was observed when enro was in a solution with 2 mM tris (2,2'-bipyridyl) ruthenium (II) and a pH 6 buffer, with an applied potential of 1.2 V and a flow rate of 1 mL/min. Using these parameters, several other fluoroquinolones were studied. It was determined that a piperazine ring in the structure was necessary for ECL to take place. Additionally, solutions containing 1-methylpiperazine and dimethylpiperazine were analyzed and ECL was observed.