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Buddha L. Mali

Bio: Buddha L. Mali is an academic researcher from University of Maryland, Baltimore County. The author has contributed to research in topics: Luminescence & Fluorescence. The author has an hindex of 8, co-authored 8 publications receiving 163 citations.

Papers
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Journal ArticleDOI
TL;DR: The findings suggest that the distance dependence of metal-enhanced phenomena such as fluorescence, phosphorescence and delayed fluorescence is underpinned by the decay of the electric near-field, and depending on the actual silver silica sample embodiment, one can see either decreased or enhanced luminescence.
Abstract: Distance dependent singlet and triplet metal-enhanced emission of eosin from silica coated silver island films (SiFs) has been studied by steady-state and time resolved fluorescence techniques, along with theoretical finite difference time domain (FDTD) numerical simulations, to understand how the thickness of the dielectric coating surrounding silver nanoparticles fundamentally affects luminescence enhancement. Our findings suggest that the distance dependence of metal-enhanced phenomena such as fluorescence, phosphorescence and delayed fluorescence is underpinned by the decay of the electric near-field, and depending on the actual silver silica sample embodiment, one can see either decreased or enhanced luminescence. These results not only expand our current MEF thinking but also suggest that one may well be able to approximate plasmon-enhanced luminescence values.

76 citations

Journal ArticleDOI
TL;DR: In this paper, the wavelength-dependent metal-enhanced fluorescence (MEF) spectrum correlates well with the plasmon specific scattering spectrum, i.e., the synchronous scatter spectrum of the silver surface of plate wells.

29 citations

Journal ArticleDOI
27 Aug 2014-PLOS ONE
TL;DR: A rapid detection assay based on microwave-accelerated metal-enhanced fluorescence which is capable of detecting the presence of 10 bacteria in unprocessed human feces within 40 seconds is developed, suggesting that this prototype biosensor has the potential to be developed into a rapid, point of care, real time diagnostic assay for C. difficile.
Abstract: Clostridium difficile is the primary cause of antibiotic associated diarrhea in humans and is a significant cause of morbidity and mortality. Thus the rapid and accurate identification of this pathogen in clinical samples, such as feces, is a key step in reducing the devastating impact of this disease. The bacterium produces two toxins, A and B, which are thought to be responsible for the majority of the pathology associated with the disease, although the relative contribution of each is currently a subject of debate. For this reason we have developed a rapid detection assay based on microwave-accelerated metal-enhanced fluorescence which is capable of detecting the presence of 10 bacteria in unprocessed human feces within 40 seconds. These promising results suggest that this prototype biosensor has the potential to be developed into a rapid, point of care, real time diagnostic assay for C. difficile.

21 citations

Journal ArticleDOI
TL;DR: In this paper, metal-enhanced fluorescence enhancement factors up to 7-fold have been observed for Basic Fuchsin (BF) in close proximity to Zinc nano particulate substrates.
Abstract: Metal-enhanced fluorescence enhancement factors up to 7-fold have been observed for Basic Fuchsin (BF) in close proximity to Zinc nano particulate substrates. In addition, the emission spectra of BF close-to Zinc as compared to a control sample are heavily distorted, particularly on the red-edge, giving systematic trends in enhancement, anywhere from 3- to 7-fold. We discuss these remarkable wavelength dependent effects with regard to the mechanism of metal-enhanced fluorescence.

15 citations

Journal ArticleDOI
TL;DR: These findings suggest two complementary methods for the enhancement: (i) surface plasmons can radiate coupled monomer and exciplex fluorescence efficiently, and (ii) enhanced absorption (enhanced electric near-field) further facilitates enhanced emission.

13 citations


Cited by
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28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal ArticleDOI
TL;DR: This work states that metal-Enhanced Fluorescence is a viable alternative to ZnO Platforms for Enhanced Directional Fluorescence Applications and that the currentzinc Oxide Nanomaterials market is likely to shrink in the coming years.
Abstract: Preface. Contributors. Mental-Enhanced Fluorescence: Progress Towards a Unified Plasmon-Fluorophore Description (Kadir Aslan and Chris D. Geddes). Spectral Profile Modifications In Metal-Enhanced Fluorescence (E. C. Le Ru, J. Grand, N. Felidj, J. Aubard, G. Levi, A. Hohenau, J. R. Krenn, E. Blackie and P. G. Etchegoin). The Role Of Plasmonic Engineering In Metal-Enhanced Fluorescence (Daniel J. Ross, Nicholas P.W. Pieczonka and R. F. Aroca). Importance of Spectral Overlap: Fluorescence Enhancement by Single Metal Nanoparticles (Keiko Munechika, Yeechi Chen, Jessica M. Smith and.David S. Ginger). Near-IR Metal Enhanced Fluorescence And Controlled Colloidal Aggregation (Jon P. Anderson, Mark Griffiths, John G. Williams, Daniel L. Grone, Dave L. Steffens, and Lyle M. Middendorf). Optimisation Of Plasmonic Enhancement Of Fluorescence For Optical Biosensor Applications (Colette McDonagh, Ondrej Stranik, Robert Nooney and Brian D. MacCraith). Microwave-Accelerated Metal-Enhanced Fluorescence (Kadir Aslan and Chris D. Geddes). Localized Surface Plasmon Coupled Fluorescence Fiber Optic Based Biosensing (Chien Chou, Ja-An Annie Ho, Chii-Chang Chen, Ming-Yaw, Wei-Chih Liu, Ying-Feng Chang, Chen Fu, Si-Han Chen and Ting-Yang Kuo). Surface Plasmon Enhanced Photochemistry (Stephen K. Gray). Metal-Enhanced Generation of Oxygen Rich Species (Yongxia Zhang, Kadir Aslan and Chris D. Geddes). Synthesis Of Anisotropic Noble Metal Nanoparticles (Damian Aherne, Deirdre M. Ledwith and John M. Kelly). Enhanced Fluorescence Detection Enabled By Zinc Oxide Nanomaterials (Jong-in Hahm). ZnO Platforms For Enhanced Directional Fluorescence Applications (H.C. Ong, D.Y. Lei, J. Li and J.B. Xu). E-Beam Lithography And Spontaneous Galvanic Displacement Reactions For Spatially Controlled MEF Applications (Luigi Martiradonna, S. Shiv Shankar and Pier Paolo Pompa). Metal-Enhanced Chemiluminescence (Yongxia Zhang, Kadir Aslan and Chris D. Geddes). Enhanced Fluorescence From Gratings (Chii-Wann Lin, Nan-Fu Chiu, Jiun-Haw Lee and Chih-Kung Lee). Enhancing Fluorescence with Sub-Wavelength Metallic Apertures (Steve Blair and Jerome Wenger). Enhanced Multi-Photon Excitation of Tryptophan-Silver Colloid (Renato E. de Araujo, Diego Rativa and Anderson S. L. Gomes). Plasmon-enhanced radiative rates and applications to organic electronics (Lewis Rothberg and Shanlin Pan). Fluorescent Quenching Gold Nanoparticles: Potential Biomedical Applications (Xiaohua Huang, Ivan H. El-Sayed, and Mostafa A. El-Sayed). Index.

398 citations

Journal ArticleDOI
TL;DR: The shell-isolated nanostructure-enhanced fluorescence, an innovative new mode for plasmon-enhancing surface analysis, is included, based on the coupling of the fluorophores in their excited states with localized surface plasmons in nanoparticles, where local field enhancement leads to improved brightness of molecular emission and higher detection sensitivity.
Abstract: Fluorescence spectroscopy with strong emitters is a remarkable tool with ultra-high sensitivity for detection and imaging down to the single-molecule level. Plasmon-enhanced fluorescence (PEF) not only offers enhanced emissions and decreased lifetimes, but also allows an expansion of the field of fluorescence by incorporating weak quantum emitters, avoiding photobleaching and providing the opportunity of imaging with resolutions significantly better than the diffraction limit. It also opens the window to a new class of photostable probes by combining metal nanostructures and quantum emitters. In particular, the shell-isolated nanostructure-enhanced fluorescence, an innovative new mode for plasmon-enhanced surface analysis, is included. These new developments are based on the coupling of the fluorophores in their excited states with localized surface plasmons in nanoparticles, where local field enhancement leads to improved brightness of molecular emission and higher detection sensitivity. Here, we review the recent progress in PEF with an emphasis on the mechanism of plasmon enhancement, substrate preparation, and some advanced applications, including an outlook on PEF with high time- and spatially resolved properties.

371 citations

Journal ArticleDOI
TL;DR: A general overview of metal-enhanced fluorescence biosensor systems from the basic mechanism to state-of-the-art biological applications and the pros and cons is provided.

275 citations

Journal ArticleDOI
TL;DR: This review describes the growing partnership between super-resolution imaging and plasmonics, by describing the various ways in which the two topics mutually benefit one another to enhance the authors' understanding of the nanoscale world.
Abstract: This review describes the growing partnership between super-resolution imaging and plasmonics, by describing the various ways in which the two topics mutually benefit one another to enhance our understanding of the nanoscale world. First, localization-based super-resolution imaging strategies, where molecules are modulated between emissive and nonemissive states and their emission localized, are applied to plasmonic nanoparticle substrates, revealing the hidden shape of the nanoparticles while also mapping local electromagnetic field enhancements and reactivity patterns on their surface. However, these results must be interpreted carefully due to localization errors induced by the interaction between metallic substrates and single fluorophores. Second, plasmonic nanoparticles are explored as image contrast agents for both superlocalization and super-resolution imaging, offering benefits such as high photostability, large signal-to-noise, and distance-dependent spectral features but presenting challenges f...

217 citations