It has been recently shown that the favorable effects of enhanced fluorescent intensities, reduced lifetimes (increased probe photostabilities), enhanced and localized rates of multiphoton excitation, and modified rates of energy transfer can occur for fluorophores or biological species of interest, in close proximity to noble metallic nano-structures and surfaces. Subsequently, nano-metal-enhanced fluorescence (NanoMEF) is yielding enormous opportunities for enhanced fluorescence sensing and imaging in microfluidics, lab-on-a-chip, clinical diagnostics, and cellular applications.
NanoMEF is a through-space phenomenon relying on interaction of fluorophores with metallic nanoparticles in the presence of excitation light. MEF can be utilized to produce nanometer-size sensors, which display enhanced spectral properties, whie still potentially maintaining a probes free space-sensing functionalities. In this presentation we report our recent findings on the effects of silver nano-particles on the spectral properties of two representative fluorescent probes for pH and Ca2+ measurements. We demonstrate that quantum efficiencies of probes are greatly enhanced providing more reliable chemical sensing capabilities. Our findings promise a new class of potential sensors, which we believe could constitute a new breed of composite nanosensors based on metal-enhanced fluorescence and their applications in miniaturized systems.
A high-performance hyperspectral imaging module with high light throughput suitable for microscopy and analytical imaging was built and tested. The imager utilizes the phenomenon of optical activity. The new technique provides information from a continuous spectral range of 250 - 1000nm. Similar spectral range extended to the near IR is also achievable. The imager has the form of a small module which can be inserted between a microscope or other imaging system and a camera. We have tested an 8-bit CCD video-rate camera with satisfactory results. The resulting instrument is simple, robust, and highly compact. The imager module is placed in-line to the microscope imaging system and does not introduce observable image aberrations. The imager is transparent to conventional imaging operations, thus with the imager in-place there is no need for reconfiguration of the microscope or switching between conventional and hyperspectral video/digital imaging modes. The presented spectral imager answers the need for a sensitive, compact, and affordable imaging spectrometer. The instrument is suited for applications requiring parallel acquisition of highly resolved concurrent spatial and spectral information such as high throughput screening, biochip analysis, remote sensing, semiconductor testing, etc. Images, spectral maps, and spectra of various fluorescent objects are presented.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.