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OpenRiver OpenRiver
Student Research and Creative Projects 2013-2014 Grants & Sponsored Projects
9-1-2013
Lithium Ion Detection Using Ligand-Capped Silver Nanoparticles Lithium Ion Detection Using Ligand-Capped Silver Nanoparticles
Ella Giovinazzo Winona State University
Jennifer Zemke Winona State University
Follow this and additional works at: https://openriver.winona.edu/studentgrants2014
Recommended Citation Recommended Citation Giovinazzo, Ella and Zemke, Jennifer, "Lithium Ion Detection Using Ligand-Capped Silver Nanoparticles" (2013). Student Research and Creative Projects 2013-2014. 13. https://openriver.winona.edu/studentgrants2014/13
This Grant is brought to you for free and open access by the Grants & Sponsored Projects at OpenRiver. It has been accepted for inclusion in Student Research and Creative Projects 2013-2014 by an authorized administrator of OpenRiver. For more information, please contact [email protected].
The goal of this research is to detect low levels of lithium ions in aqueous samples using silver nanoparticles. Lithium is used in many drugs, lithium ion batteries and is even being looked at as an additive to drinking water. Lithium ions are known to have mood-altering effects on the body.1 This can lead disrupt thyroid function.4 Thus being aware of the concentration of Li+ in aqueous solutions is pertinent in preventing these complications . Silver nanoparticles capped with a specific ligand can attach to ions and can allow for a measurement of the concentration of that ion in solution.
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Figure 1 shows the first timelapse of the lithium in solution over a period of time. This helps in determining the time period that the ligand and nanoparticles need to attach to the ions.
y = 0.0269x + 0.0053R² = 0.9761
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Figure 2 is that of the standard curve to see if we could view a color change at different lithium ion concentrations. As expectedthe 2ppm solution showed very little change compared to the 10ppm solution.
Figure 3 is a different graph of the stand curve of the two lowest concentrations. As the concentration of lithium increases more nanoparticles are brought closer together in solution yielding a different absorption spectrum.
Figure 5 shows the absorption shifts for sodium, lithium, and potassium at the same concentration to determine how selective the ligand capped nanoparticles are to lithium ions.
The last figure, Figure 6, shows another way to look at the absorbance of each ion tested. Lithium and potassium are very closely related.
From all this data this shows that our ligand is not extremely selective to lithium due to the binding of sodium and potassium however our nanoparticles bind lithium 50 fold better than the pervious lithium binding literature.3
To continue with this experimentation it would be useful to determine if the anion is disrupting the absorbance of the particles. This would be helpful in seeing if the ligand could be more selective to lithium than what the data has previously stated. Control solutions with chloride counter ions will be assessed. This ligand could however be very selective to other ions and these avenues will be researched.
1.Lithium's effect on depression clarified, MITCH WALDROP, Chemical & Engineering News Archive 1979 57 (19), 16-17 2.Ying Zhou, Hong Zhao, Yujian He, Nan Ding, Quian Cao, Colorimetric Detection of Cu2+ using 4-mercaptobenzoic acid Modified Silver Nanoparticles, China, 2011.3. Sherine O. Obare, Rachel E. Hollowell, and Catherine J. Murphy, Sensing Strategy for Lithium Ion Based on Gold Nanoparticles, South Carolina, 2002.4.Lithium treatment and thyroid abnormalities, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1584230/ April 4, 2014
For this experiment a method based on another paper using silver nanoparticles and Copper.2 The silver nanoparticles in this study are synthesized by reducing silver nitrate with NaBH4. A specific ligand, 3,4-dimethoxythiophenol, is used to cap the nanoparticles and allows for the binding of Li+ ions.
The Li+ ions bind to two nanoparticles bringing them together in solution resulting in a color change which is detectable by UV-Vis spectroscopy. There is a required wait time of 60 minutes to allow for the process above to happen.
The picture above shows the color change of yellow to grey which is due to the presentence of yellow and purple nanoparticles.
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The sodium spectrum is different than lithium and potassium. Figure 6 does shows that our ligand is not specific in bind lithium ions.
I wish to thank WSU for founding through a student research grant. Also I want to thank Dr. Zemke for putting up with me.
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2ppm Lithium Comparison against 4ppm
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Ion Comparison at 10ppm Concentration
Appendix C
RESEARCH / CREATIVE PROJECT ABSTRACT / EXECUTIVE SUMMARY FINAL REPORT FORM
Title of Project Lithium Ion Detection Using Ligand-Capped Silver Nanoparticles
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Student Name Ella Giovinazzo Faculty Sponsor Dr. Jennifer Zemke Department WSU Chemistry
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Abstract The goal of this research is to detect low levels of lithium ions in aqueous samples
using silver nanoparicles. Lithium is used in many drugs, lithium ion batteries and is
even being looked at as an additive to drinking water. Lithium ions are known to have
mood-altering effects on the body but can also disrupt thyroid function. Thus being
aware of the concentration of Li+ in aqueous solutions is pertinent in preventing
these complications. The silver nanoparticles in this study are synthesized by
reducing silver nitrate with NaBH4. A specific ligand, 3,4- dimethoxythiophenol, is
used to cap the nanoparticles and allows for the binding of Li+ ions. The Li+ ions
bind to two nanoparticles bringing them together in solution resulting in a color
change which is detectable by UV-Vis spectroscopy. Our current method requires a 60
minute incubation period as determined by monitoring the absorbance spectrum over
time. Analysis is currently underway to determine the detection limit and selectivity
of these ligand-capped nanoparticles
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The end product of this project in electronic format has been submitted to the Provost/Vice President for Academic Affairs via the Office of Grants & Sponsored Projects Officer (Maxwell 161, [email protected]).
Student Signature Date Faculty Sponsor Signature Date