Grantee Research Project Results
Final Report: Increased Sensitivity for Lead Detection in Drinking Water Using Surface Enhanced Raman Spectroscopy (SERS)
EPA Grant Number: SU840170Title: Increased Sensitivity for Lead Detection in Drinking Water Using Surface Enhanced Raman Spectroscopy (SERS)
Investigators: Dong, Lifeng , Walsh, Alex , Wendorf, Kyle , Coffler, Samantha , Grace, Sideena , Sowinski, Maddie , Sedarski, Josh , Morales-Balbuena, Raphael , McCutchen, Sydney
Institution: Hamline University
EPA Project Officer: Spatz, Kyle
Phase: I
Project Period: December 1, 2020 through November 30, 2021
Project Amount: $24,518
RFA: P3 Awards: A National Student Design Competition Focusing on People, Prosperity and the Planet (2020) RFA Text | Recipients Lists
Research Category: P3 Awards , P3 Challenge Area - Safe and Sustainable Water Resources
Objective:
Currently, many lead detection methods exist to provide communities with vital information that help them to make informed decisions on how to handle infrastructure and contamination. However, many of these methods utilize instruments and chemicals that are inaccessible and unsustainable for many of the communities that need detection methods the most, such as low-income and rural communities. The objective of this is to provide a more affordable, accessible, yet ultrasensitive method of lead detection based on surface enhanced Raman spectroscopy (SERS).
Summary/Accomplishments (Outputs/Outcomes):
Several different methodologies were explored in an attempt to find a high quality accessible and affordable lead detection method. The main methodology employed consisted of a substrate approach utilizing a gold-coated silicon substrate coated with L-cysteine, gold nanoparticles, ATP and then lead to form aggregations. Upon the addition of lead, bonded 4-ATP signals were to be characterized by Raman spectroscopy. These samples did not display Raman signals leading to more work to be done to make this a feasible model. A similar method, creating probe molecule solutions of L-cysteine, gold or silver nanoparticles, 4-ATP, and lead nitrate. These solutions were then characterized by Raman spectroscopy. This method yielded a lead detection limit of 1.02 mM. However, this method has not proved to be repeatable, there have been variable results between trials.
A lead detection method using nanocolorimetry and smartphone micrography was also employed by our research team. Solutions of lead chromate precipitate were formed by combining lead nitrate dilutions and potassium chromate. The vibrant yellow lead chromate precipitates are photographed. Preliminary experiments show promising results as a detection limit of 250 μM for bright field micrography and 0.503 nM for dark field micrography. This project is continuing at least through the end of the 2021-2022 school year. Finally, our team analyzed the Raman signals of lead chromate. Preliminary results obtained significant signals, which were determined to be those of potassium chromate rather than lead chromate. Additional research needs to be done to isolate the lead chromate signal for this method to be practical.
Journal Articles:
No journal articles submitted with this report: View all 4 publications for this projectSupplemental Keywords:
lead detection, surface enhanced Raman spectroscopy, scanning electron microscope, nanocolorimetryRelevant Websites:
Phase I abstract, Phase II presentation, Hamline Oracle Exit
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.