CMOP Undergraduate Intern Mentoring Opportunity
Deadline: March 27, 2009
Selections Announced: April 3, 2009
Name/Title/Institution(s) of senior mentor(s): Joseph Needoba/Assistant Professor/OHSU, Zanna Chase/Assistant Professor/OSU. Andrew Barnard/VP Research/Wet Labs.
Name/Title/Institution(s) of frontline mentor(s): Florian Moeller, OHSU
Project Title:
Role of Dissolved Organic Carbon in Fluorescence-based Chemical Assays of Ammonium and Zinc.
Context for Project:
In situ biogeochemical sensors are now an integral component of the CMOP scientific program, and many of these sensors are currently being integrated into the SATURN collaboratory. One of the most advanced technologies being employed is represented by the wet chemistry-based systems. The SubChem APNA system was recently acquired through the Murdock Trust award to CMOP, and other similar systems are being developed and deployed by Zanna Chase at OSU and Andrew Barnard at Wet Labs.One common method across all these systems is the use of fluorescence-based chemicalassays to determine concentrations of important analytes such as ammonium and zinc. Although well described for laboratory bench-top assays, the fluorescence-based methods have only recently been applied to in situ instrumentation, and therefore it remains uncertain what effect water quality and in situ environmental reaction conditions will have on the chemical assays. This project is intended to further our understanding of the use of fluorescence-based assays for in situ deployment conditions of the Columbia River and Estuary, which is essential to know for upcoming deployments in the SATURN collaboratory.
Brief Description.The intern will conduct a series of laboratory experiments to determine the effects of key environmental variables on the fluorescence properties of the chemical assays for ammonium and zinc in river and coastal waters. Both assays are employed for in situ applications by the senior mentors of the project, and the instruments arebeing prepared for deployment in summer 2009. Two primary investigations will be undertaken: 1) to determine the role of fluorescence quenching by dissolved organic carbon on the fluorescence signal of the assays, and 2) determine the role of temperature on the quantum efficiency of the fluorophores of interest. It is essential to determine these effects in order to produce quality data with the in situ sensors. The intern willbe based in Needoba’s lab for the duration of the program, but will be expected to spend time in Chase’s lab at OSU to learn the zinc assay methodology. In addition, the intern will be expected to interact with the instrument development group at Wet Labs, who are in the implementation phase of a fluorescence based ammonium analyzer. Video conferencing and visits by the PI’s will be used to create a free-flowing interactive environment across the three locations.
Proposed Outcomes/Broader Impact:The project addresses an important unknown sensor development question and therefore addresses a number of CMOP goals. In addition, the project will improve the data quality of the SubChem APNA system and other in situ fluorescence systems that will be deployed this year on SATURN platforms. We anticipate that the project will lead to a publication in an internationally recognized scientific journal such as Limnology and Oceanography Methods.
Proposed timeline (within a 10 week span):
Week 1: Needoba lab – Introduction to project, literature review
Week 2: Needoba lab – Method development (with F. Moeller)
Week 3: Needoba lab – Sample collection and NH4+ fluorescence measurements (F. Moeller)
Week 4: Needoba lab –Determine role of DOC on quenching of NH4+ fluorescence (F. Moeller)
Week 5:Needoba lab – Determine role of temperature on quantum efficiency of NH4+ fluorescence
Week 6:Chase lab – Learn Zn chemistry
Week 7:Chase lab/Needoba lab– Determine role of DOC on quenching of Zn fluorescence
Week 8:Chase lab/Needoba lab – Determine role of temperature on quantum efficiency of Zn fluorescence
Week 9:Needoba lab – Data analysis
Week 10:Needoba lab – final report due/ outline of scientific paper due.
Intern academic experience and skill set should include: Chemistry, oceanography, engineering, or environmental science. Some background in aquatic biology or biogeochemistry would be helpful. Previous laboratory experience in a chemistry or biology lab is essential. Background experience in optics or instrumentation is helpful. Prefer a junior or senior candidate.