Maximizing Dye Fluorescence Via Incorporation of Metallic Nanoparticles In Solution

Xu, Y., Lei, G., Booker, A. C., Linares, K. A., Fleming, D. L., Meehan, K., Lu, G.-Q., Love, N. G., Love, B. J. and Sobek, D. (2004) Maximizing Dye Fluorescence Via Incorporation of Metallic Nanoparticles In Solution. Lab-on-a-Chip: Platforms, Devices, and Applications, Philadelphia, PA, USA, 25 Oct 2004. pp. 174-184. (doi: 10.1117/12.571309)

Abstract

Gram-negative bacteria initiate a stress response in which the cells efflux potassium when electrophilic toxins are introduced into their environment. Hence, measurement of K+ concentration in the surrounding water using a fluorescence-based potassium-selective optode has been proposed for environmental and homeland security applications. Unfortunately, the fluorophore commonly used in such an optode is inefficient. Surface enhanced fluorescence (SEF) can be used to increase its fluorescence efficiency, which will improve the sensor's performance. To understand this phenomenon before applying it to the optode system, Rose Bengal (RB), an inexpensive and well characterized dye, in solution with gold and silver nanoparticles was studied. As expected, fluorescence from RB-gold solutions was low since alignment of gold's surface plasmon resonance (SPR) peak and absorption and fluorescence energies in RB favored energy transfer from RB to the gold nanoparticles. The alignment of the silver's SPR peak and the RB transitions favored transfer from silver to RB. SEF was observed in solutions with large dye-to-silver separation. However, little fluorescence was observed when the solution was pumped at the silver's SPR peak. Fluorescence from the dye decreased as dye-to-silver separation decreased. An explanation for these observations is presented; additional research is needed to develop a complete understanding.

• Item Type: Conference or Workshop Item
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Meehan, Professor Kathleen
• Authors: Xu, Y., Lei, G., Booker, A. C., Linares, K. A., Fleming, D. L., Meehan, K., Lu, G.-Q., Love, N. G., Love, B. J., and Sobek, D.
• College/School: College of Science and Engineering > School of Engineering
• ISSN: 0277-786X