Monitoring Metal Pesticide Complex in Biological Matrices Using Electro Spray Ionization Mass Spectrometry

Griffin Boone, Grady Blacken, Chemistry, Bellevue Collge 3000 Landerholm Cir SE, Bellevue, WA 98007

Separation of proteins using metal-ligand complexes is a well-established practice in the field of bioengineering and biochemistry. ESI-MS (electrospray ionization mass spectrometry) can be used to identify biological and organic molecules. Previous studies have detected chelated metal ions using ESI-MS, this project focuses on the identification of a metal-ligand complex comprised of a tridentate chelating agent IDA (Iminodiacetic acid) and a bidentate ligand, Histidine. By coordinating copper with IDA a binary complex is formed, this allows for the detection of copper by proxy of the IDA. By selecting a unique fragment related to IDA we can target in MS/MS (tandem mass spectrometry) for greater sensitivity; the complex can be selected for analysis out of solution. We will use this novel approach to build a parent-ion scanning technique to monitor metal-ligand complexes extracted from environmental matrices. First, the ideal solution parameters are determined to maximize the complex formation and detection of the Cu-IDA complex. So far, a high ratio of copper to IDA coupled with a basic buffer has yielded the best data. Creating a ternary complex comprised of copper IDA and an imidazole ring-containing compound, histidine. Selectively turning to the peaks associated with the copper IDA complex, the ternary complexes can be selected for in-depth analysis of its structure and bonding properties. Future work could focus on identification of the metal-ligand complexes from soil samples with other compounds containing imidazole rings such as the neonicotinoid imidacloprid which has been indicated in bee colony collapse. By chelating solid with IDA complex formed from pentacoordinate copper ions could be detected despite the low relative concentration. 

Additional Abstract Information

Presenter: Griffin Boone

Institution: University of Washington

Type: Poster

Subject: Biochemistry

Status: Approved

Time and Location

Session: Poster 2
Date/Time: Mon 3:00pm-4:00pm
Session Number: 2513