Proceedings Volume 9523

International Conference on Nano-Bio Sensing, Imaging, and Spectroscopy 2015

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Proceedings Volume 9523

International Conference on Nano-Bio Sensing, Imaging, and Spectroscopy 2015

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Volume Details

Date Published: 8 July 2015
Contents: 16 Sessions, 23 Papers, 0 Presentations
Conference: International Conference on Nano-Bio Sensing, Imaging, and Spectroscopy 2015 2015
Volume Number: 9523

Table of Contents

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Table of Contents

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  • Front Matter: Volume 9523
  • Micro-Nano Biosensing Technology
  • Biomedical Application of Optical Biosensors I
  • Advanced Bio-Imaging
  • Wavefront Imaging Techniques
  • Nanoplasmonic Sensors
  • Emerging Microscopic Techniques
  • Biomedical Application of Optical Biosensors II
  • In-Vivo Imaging for Clinical Applications
  • Emerging Technologies for Bio-Detection
  • Poster Session: High Resolution Imaging, Sensing, and Manipulation
  • Poster Session: Optical Imaging of Bio-Nano Systems
  • Poster Session: Molecular Optical Biosensing
  • Poster Session: Light Scattering-Based Biomedical Imaging
  • Poster Session: Biomedical Application of Optical Biosensors
  • Poster Session: Emerging Technologies for Bio-Detection
Front Matter: Volume 9523
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Front Matter: Volume 9523
This PDF file contains the front matter associated with SPIE Proceedings Volume 9523, including the Title Page, Copyright information, Table of Contents, and Conference Committee listing.
Micro-Nano Biosensing Technology
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Smart point-of-care systems for molecular diagnostics based on nanotechnology: whole blood glucose analysis
Jasmine P. Devadhasan, Sanghyo Kim
Complementary metal oxide semiconductor (CMOS) image sensors are received great attention for their high efficiency in biological applications. The present work describes a CMOS image sensor-based whole blood glucose monitoring system through a point-of-care (POC) approach. A simple poly-ethylene terephthalate (PET) film chip was developed to carry out the enzyme kinetic reaction at various concentrations of blood glucose. In this technique, assay reagent was adsorbed onto amine functionalized silica (AFSiO2) nanoparticles in order to achieve glucose oxidation on the PET film chip. The AFSiO2 nanoparticles can immobilize the assay reagent with an electrostatic attraction and eased to develop the opaque platform which was technically suitable chip to analyze by the camera module. The oxidized glucose then produces a green color according to the glucose concentration and is analyzed by the camera module as a photon detection technique. The photon number decreases with increasing glucose concentration. The simple sensing approach, utilizing enzyme immobilized AFSiO2 nanoparticle chip and assay detection method was developed for quantitative glucose measurement.
Biomedical Application of Optical Biosensors I
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High content cell-based assay for the inflammatory pathway
Abhishek Mukherjee, Joon Myong Song
Cellular inflammation is a non-specific immune response to tissue injury that takes place via cytokine network orchestration to maintain normal tissue homeostasis. However chronic inflammation that lasts for a longer period, plays the key role in human diseases like neurodegenerative disorders and cancer development. Understanding the cellular and molecular mechanisms underlying the inflammatory pathways may be effective in targeting and modulating their outcome. Tumor necrosis factor alpha (TNF-α) is a pro-inflammatory cytokine that effectively combines the pro-inflammatory features with the pro-apoptotic potential. Increased levels of TNF-α observed during acute and chronic inflammatory conditions are believed to induce adverse phenotypes like glucose intolerance and abnormal lipid profile. Natural products e. g., amygdalin, cinnamic acid, jasmonic acid and aspirin have proven efficacy in minimizing the TNF-α induced inflammation in vitro and in vivo. Cell lysis-free quantum dot (QDot) imaging is an emerging technique to identify the cellular mediators of a signaling cascade with a single assay in one run. In comparison to organic fluorophores, the inorganic QDots are bright, resistant to photobleaching and possess tunable optical properties that make them suitable for long term and multicolor imaging of various components in a cellular crosstalk. Hence we tested some components of the mitogen activated protein kinase (MAPK) pathway during TNF-α induced inflammation and the effects of aspirin in HepG2 cells by QDot multicolor imaging technique. Results demonstrated that aspirin showed significant protective effects against TNF-α induced cellular inflammation. The developed cell based assay paves the platform for the analysis of cellular components in a smooth and reliable way.
Nanomaterial-based optical sensors for sensitive detection of heavy metal ions
Shasha Wang, Lingxin Chen
Nanometerial-based optical nanoprobes have been extensively developed because of their high sensitivity, good specificity, and potential for easy quantification of species in chemical and biological analysis. With the development of nanotechnology, various kinds of nanomaterials with novel optical properties have heen generated, laying the foundation of optical nanoprobes. By further integrating receptors (chemical ligand, aptamer, molecular imprinting polymer, etc.), the information of binding specific targets will transform into analytically optical signals by employing different detection techniques including colorimetry/UV-Vis spectra, fluorometry and surface enhanced Raman scattering (SERS). In this presentation, firstly, we introduced a simple, rapid and ultrasensitive SERS nanosensor for mercury ion (Hg2+) detection based on the 4-mercaptopyridine (4-MPY) functionalized silver nanoparticles (AgNPs) in the presence of spermine; then, a novel colorimetric nanosensor for mercury species was developed for the first time due to the analyte-induced aggregation of gold nanoparticles (AuNPs) with the assistance of a thiol-containing ligand of diethyldithiocarbamate (DDTC); finally, the sensitive and selective recognition and detection of trypsin was realized in a SERS strategy by using anti-aggregation of 4-MPY-functionalized AgNPs on the basis of the interaction between protamine and trypsin.
Graphene oxide-stimulated myogenic differentiation of C2C12 cells on PLGA/RGD peptide nanofiber matrices
Y. C. Shin, J. H. Lee, M. J. Kim, et al.
During the last decade, much attention has been paid to graphene-based nanomaterials because they are considered as potential candidates for biomedical applications such as scaffolds for tissue engineering and substrates for the differentiation of stem cells. Until now, electrospun matrices composed of various biodegradable copolymers have been extensively developed for tissue engineering and regeneration; however, their use in combination with graphene oxide (GO) is novel and challenging. In this study, nanofiber matrices composed of poly(lactic-co-glycolic acid, PLGA) and M13 phage with RGD peptide displayed on its surface (RGD peptide-M13 phage) were prepared as extracellular matrix (ECM)-mimicking substrates. RGD peptide is a tripeptide (Arg-Gly-Asp) found on ECM proteins that promotes various cellular behaviors. The physicochemical properties of PLGA and RGD peptide-M13 phage (PLGA/RGD peptide) nanofiber matrices were characterized by atomic force microscopy, Fourier-transform infrared spectroscopy and thermogravimetric analysis. In addition, the growth of C2C12 mouse myoblasts on the PLGA/RGD peptide matrices was examined by measuring the metabolic activity. Moreover, the differentiation of C2C12 mouse myoblasts on the matrices when treated with GO was evaluated. The cellular behaviors, including growth and differentiation of C2C12 mouse myoblasts, were substantially enhanced on the PLGA/RGD peptide nanofiber matrices when treated with GO. Overall, these findings suggest that the PLGA/RGD peptide nanofiber matrices can be used in combination with GO as a novel strategy for skeletal tissue regeneration.
Advanced Bio-Imaging
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Principles and application of intrinsic Förster resonance energy transfer (iFRET) for label-free detection of native proteins
Hyo Jin Kang, Ju Hwan Kim, Amar B. T. Ghisaidoobe, et al.
Tryptophan residues in proteins of interest were evaluated as FRET donors to facilitate the development of a label-free protein detection system, coined "intrinsic Förster (or fluorescence) resonance energy transfer (iFRET)". iFRET fluorescence probes, composed of an efficient and tryptophan-specific FRET acceptor in addition to a target protein-specific ligand, selectively bind to the target proteins thereby enabling Förster resonance energy transfer between the protein tryptophan residues and the iFRET probe. We have developed efficient iFRET acceptor fluorophores and a deep UV microscope, which were successfully applied to detect native target proteins in live cells.
Wavefront Imaging Techniques
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Dark-field spectral imaging microscope for localized surface plasmon resonance-based biosensing
Sang-Youp Yim, Jin-Ho Park, Min-Gon Kim
Localized surface plasmon resonance (LSPR) of metal nanoparticles makes red-shift of extinction wavelength with an increase in the refractive index at the surface of the metal nanoparticles. Since biomolecules bound to the metal nanoparticle’s surface induce refractive index change, biosensing based on LSPR effect can be possible by monitoring scattering or absorption spectrum changes. Generally, however, conventional method detects ensemble averaged LSPR signal of a huge number of metal nanoparticles. Here, we have constructed a dark-field spectral imaging microscope in order to monitor the scattering spectra of individual metal nanoparticles, simultaneously. Gold nanorod (GNR) and aptamer are employed to detect ochratoxin A (OTA) related to a carcinogenic illness. An aptamer-target binding mechanism promotes wavelength shift of extinction spectra due to refractive index change within sensing volume of GNR by structural change of aptamer. A number of GNRs can be identified in a dark-field LSPR image, simultaneously. A typical spectrum of a GNR exhibits red-shift after target binding of molecules and OTA detection is extended to the very low concentration of 1 pM level.
Nanoplasmonic Sensors
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Engineering optical near-fields for highly efficient surface-enhanced nanoplasmonics
We have numerically analyzed the effect of geometrical parameters of circular, rhombic, and square nanostructure arrays when light fields are localized based on surface-enhanced nanoplasmonics. It was found that subdiffraction-limited field localization can be achieved using the nanostructures. We have also discussed various approaches to implement superresolution imaging systems using the obtained localized fields. The localized field can be used to implement colocalized light matter distribution with much enhanced sensitivity in surface plasmon resonance biosensor and more interestingly for super-resolution full-field microscopy.
Dual-modal silica nanoprobes with surface enhanced Raman spectroscopic and fluorescent signals
We present that dual-modal silica nanoprobes based on surface enhanced Raman spectroscopy (SERS) and fluorescence, demonstrating the several combinations of two spectroscopic signals for the noble combinatorial nanoprobes (F-SERS dot). Their synthetic procedure was introduced and dual-modal spectroscopic analyses were performed as preliminary studies. Hopefully, F-SERS dots will be one of promising and multifunctional nanoprobes for the various in vitro and in vivo biological diagnoses and screenings.
Emerging Microscopic Techniques
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Observation of Brownian motion of a micrometer-size bead in water by off-axis digital holographic microscopy
Yoon-Sung Bae, Phil-Jun Jeon, Hee-Jung Lee
An effective volumetric measurement method for determination of the 3D position of a single particle based on off-axis digital holographic microscopy is presented in this paper. 3 μm polystyrene bead suspended water is used as a particle to be traced in our experiment. We have demonstrated the feasibility of our method by observing the bead undergoing Brownian motion in water by implemented setup. For fast determination, a series of transverse intensity images are numerically reconstructed from a single hologram of the bead, then centroid technique is applied to the reconstructed images for enhancing the position resolution. Nano-meter scale resolution with a frame rate of 30 is achieved in this experiment in both lateral and transverse direction.
Biomedical Application of Optical Biosensors II
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A simple gel electrophoresis method for separating polyhedral gold nanoparticles
Suhee Kim, Hye Jin Lee
In this paper, a simple approach to separate differently shaped and sized polyhedral gold nanoparticles (NPs) within colloidal solutions via gel electrophoresis is described. Gel running parameters for separating efficiently gold NPs including gel composition, added surfactant types and applied voltage were investigated. The plasmonic properties and physical structure of the separated NPs extracted from the gel matrix were then investigated using transmission electron microscopy (TEM) and UV-vis spectrophotometry respectively. Data analysis revealed that gel electrophoresis conditions of a 1.5 % agarose gel with 0.1 % sodium dodecyl sulfate (SDS) surfactant under an applied voltage of 100 V resulted in the selective isolation of ~ 50 nm polyhedral shaped gold nanoparticles. Further efforts are underway to apply the method to purify biomolecule-conjugated polyhedral Au NPs that can be readily used for NP-enhanced biosensing platforms.
Analysis of antifreeze protein activity using colorimetric gold nanosensors
Xu Jing, Ho-seok Choi, Ji-In Park, et al.
High activity and long stability of antifreeze proteins (AFPs), also known as ice-binding proteins (IBPs), are necessary for exerting their physiological functions in biotechnology and cryomedicine. Here we report a simple analysis of antifreeze protein activity and stability based on self-assembly of gold nanoparticles (AuNPs) via freezing and thawing cycles. While the mercaptosuccinic acid-capped AuNP (MSA-AuNP) was easily self-assembled after a freezing/thawing cycle, due to the mechanical attack of ice crystal on the MSA-AuNP surface, the presence of AFP impeded the self-assembly of MSA-AuNP via the interaction of AFP with ice crystals via freezing and thawing cycles, which led to a strong color in the MSA-AuNP solution. As a result, the aggregation parameter (E520/E650) of MSA-AuNP showed the rapid detection of both activity and stability of AFPs. We suggest that our newly developed method is very suitable for measuring antifreeze activity and stability in a simple and rapid manner with reliable quantification.
In-Vivo Imaging for Clinical Applications
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The gap-plasmonic effect induced on a silver nanoisland substrate for surface-enhanced Raman spectroscopy
Hyerin Song, Jong-ryul Choi, Wonju Lee, et al.
This research is about surface-enhanced Raman spectroscopy based on the gap-plasmonic effects between the silver nanoisland (AgNI) substrate and gold nanoparticles (AuNPs). With calculation, we prove that plasmonic-coupling phenomena between AuNPs and AgNIs were formed, which eventually affect to the signal enhancements, and we simulate the field enhancement according to the AuNPs position on the AgNI substrates. Consequently, we experimentally confirm the Raman signal enhancement using target as AuNP attached DNA, which were distributed on the AgNIs substrate randomly. Raman spectra measured on the AgNI substrate exhibit approximately 20-fold signal enhancements compare to the signals measured on a uniform silver film, and the experimental spectra agreed well with the results of simulation. This method has merit in that significant Raman signal enhancements can be achieved for large areas without a complicated nano-lithographic process.
A fiber optic probe coupled low-cost CMOS-camera-based system for simultaneous measurement of oxy-, deoxyhemoglobin, and blood flow
Myeongsu Seong, Zephaniah Phillips V, Phuong Minh Mai, et al.
Appropriate oxygen supply and blood flow are important in coordination of body functions and maintaining a life. To measure both oxygen supply and blood flow simultaneously, we developed a system that combined near-infrared spectroscopy (NIRS) and diffuse speckle contrast analysis (DSCA). Our system is more cost effective and compact than such combined systems as diffuse correlation spectroscopy(DCS)-NIRS or DCS flow oximeter, and also offers the same quantitative information. In this article, we present the configuration of DSCA-NIRS and preliminary data from an arm cuff occlusion and a repeated gripping exercise. With further investigation, we believe that DSCA-NIRS can be a useful tool for the field of neuroscience, muscle physiology and metabolic diseases such as diabetes.
Emerging Technologies for Bio-Detection
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The study of structural color filter based on periodic nanohole arrays for bio-detection
Seunguk Kim, Jeonghee Shin, Seungjun Yoo, et al.
A nanostructure which induces localized surface plasmon resonance (LSPR) can be utilized in visible light and near infrared (NIR) regions and it shows promising features as a bio-detector because LSPR state is changed easily by different bio-related materials. Owing to transparent property of many biomolecules as well as diluted states in base solutions, it is hard to distinguish each other by eye or microscope analysis. However, difference in molecular structure and composition makes difference in optical characteristics such as a refractive index or a dielectric constant. Therefore, our LSPR-based nanohole array structure which has high sensitivity to detect small changes in optical characteristics can be a great candidate for a bio detector. Here, we fabricated structural color filters (SCFs) to detect wavelength shifts for several biomolecules and optimized the nanohole array structures for high sensitivity. Periodic nanohole arrays were designed to present resonance peaks in visible light region for optical analysis and fabricated in Au or Al thin film layer. The spectral shifts were detected caused by biomolecules.
Poster Session: High Resolution Imaging, Sensing, and Manipulation
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High-contrast imaging of mycobacterium tuberculosis using third-harmonic generation microscopy
Nonlinear optical microcopy has become an important tool in investigating biomaterials due to its various advantages such as label-free imaging capabilities. In particular, it has been shown that third-harmonic generation (THG) signals can be produced at interfaces between an aqueous medium (e.g. cytoplasm, interstitial fluid) and a mineralized lipidic surface. In this work, we have demonstrated that label-free high-contrast THG images of the mycobacterium tuberculosis can be obtained using THG microscopy.
Poster Session: Optical Imaging of Bio-Nano Systems
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Subdiffraction-limited axial imaging of live cells using linear nanoaperture arrays based on extraordinary transmission
Wonju Lee, Jong-ryul Choi, Kyujung Kim, et al.
We have considered linear nanoaperture arrays for super-resolved live cell imaging. The nanoaperture arrays consist of nanoholes of varying diameter. Each nanohole localizes near-field distribution and produces extraordinary optical transmission (EOT) by surface plasmon localization. Much deeper light penetration was achieved in EOT than under total internal reflection. The results can be used to implement subdiffraction-limited axial resolution when applied to microscopy.
Poster Session: Molecular Optical Biosensing
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Novel measurement of blood velocity profile using translating-stage optical method and theoretical modeling based on non-Newtonian viscosity model
Detailed knowledge of the blood velocity distribution over the cross-sectional area of a microvessel is important for several reasons: (1) Information about the flow field velocity gradients can suggest an adequate description of blood flow. (2) Transport of blood components is determined by the velocity profiles and the concentration of the cells over the cross-sectional area. (3) The velocity profile is required to investigate volume flow rate as well as wall shear rate and shear stress which are important parameters in describing the interaction between blood cells and the vessel wall.

The present study shows the accurate measurement of non-Newtonian blood velocity profiles at different shear rates in a microchannel using a novel translating-stage optical method. Newtonian fluid velocity profile has been well known to be a parabola, but blood is a non-Newtonian fluid which has a plug flow region at the centerline due to yield shear stress and has different viscosities depending on shear rates. The experimental results were compared at the same flow conditions with the theoretical flow equations derived from Casson non-Newtonian viscosity model in a rectangular capillary tube. And accurate wall shear rate and shear stress were estimated for different flow rates based on these velocity profiles. Also the velocity profiles were modeled and compared with parabolic profiles, concluding that the wall shear rates were at least 1.46-3.94 times higher than parabolic distribution for the same volume flow rate.
Poster Session: Light Scattering-Based Biomedical Imaging
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Highly sensitive immunoassay of anti-cyclic citrullinated peptide marker using surface-enhanced Raman scattering detection
H. Chon, S. Lee, R. Wang, et al.
We report a highly sensitive anti-cyclic citrullinated peptide (anti-CCP) detection method for early diagnosis of rheumatoid arthritis (RA) using surface-enhanced Raman scattering (SERS)-based immunoassay. Herein, cyclic citrullinated peptide (CCP)-conjugated magnetic beads and anti-human IgG-conjugated hollow gold nanospheres (HGNs) were used as substrates and SERS nano-tags, respectively. First, its detection sensitivity was evaluated using anti-CCP standard solutions. Then quantitative anti-CCP levels, determined by the SERS-based assay, were compared with those obtained from three commercially available anti-CCP assay kits (Immunoscan CCPlus, ImmunnLisa CCP and BioPlex 2200) to assess its potential utility as a clinical tool. Finally, clinical samples from 20 RA patients were investigated using them. In the SERS-based assay, the anti-CCP level in human serum was successfully determined by monitoring the characteristic Raman peak intensity of SERS nano-tags. The diagnostic performance of our SERS-based immunoassay for clinical samples shows a good agreement with those measured by three commercial anti-CCP kits. In addition, our SERS-based assay results are more consistent in the low concentration range (0–25 U/mL) than those achieved by the commercial kits. Accordingly, it is estimated that the SERS-based assay is a potentially useful diagnostic tool for early diagnosis of RA.
Poster Session: Biomedical Application of Optical Biosensors
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Integrated optical refractometer based on bend waveguide with air trench structure
Jin Hwa Ryu, Jaehoon Park, Chan-mo Kang, et al.
This study proposed a novel optical sensor based on a refractometer integrating a bend waveguide and a trench structure. The optical sensor is a planar lightwave circuit (PLC) device involving a bend waveguide with maximum optical loss. A trench structure was aligned with the partially exposed core layer’s sidewall of the bend waveguide, providing a quantitative measurement condition. The insertion losses of the proposed 1 x 2 single-mode optical splitter-type sensor were 4.38 dB and 8.67 dB for the reference waveguide and sensing waveguide, respectively, at a wavelength of 1,550 nm. The optical loss of the sensing waveguide depends on the change in the refractive index of the material in contact with the trench, but the reference waveguide had stable optical propagating characteristic regardless of the variations of the refractive index.
Probabilistic approach for sensing performances of localized surface plasmon resonance biosensors
Heejin Yang, Wonju Lee, Taewon Hwang, et al.
We analyze sensing performances of localized surface plasmon resonance biosensors based on the overlap between target distribution and local field intensity produced by silver nanoislands in three detection models of non-specific, non-colocalized, and colocalized detection. The behavior of biomolecules was modeled to follow a probabilistic model using Poisson distribution. The results have found that the colocalized detection achieves the highest overlap signature with the smallest uncertainty and can enhance the limit of detection by more than 10000 times compared to conventional non-specific detection.
Poster Session: Emerging Technologies for Bio-Detection
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NIR-emitting molecular-based nanoparticles as new two-photon absorbing nanotools for single particle tracking
J. Daniel, A. G. Godin, G. Clermont, et al.
In order to provide a green alternative to QDs for bioimaging purposes and aiming at designing bright nanoparticles combining both large one- and two-photon brightness, a bottom-up route based on the molecular engineering of dedicated red to NIR emitting dyes that spontaneously form fluorescent organic nanoparticles (FONs) has been implemented. These fully organic nanoparticles built from original quadrupolar dyes are prepared using a simple, expeditious and green protocol that yield very small molecular-based nanoparticles (radius ~ 7 nm) suspension in water showing a nice NIR emission (λem=710 nm). These FONs typically have absorption coefficient more than two orders larger than popular NIR-emitting dyes (such as Alexa Fluor 700, Cy5.5 ….) and much larger Stokes shift values (i.e. up to over 5500 cm-1). They also show very large two-photon absorption response in the 800-1050 nm region (up to about 106 GM) of major promise for two-photon excited fluorescence microscopy. Thanks to their brightness and enhanced photostability, these FONs could be imaged as isolated nanoparticles and tracked using wide-field imaging. As such, thanks to their size and composition (absence of heavy metals), they represent highly promising alternatives to NIR-emitting QDs for use in bioimaging and single particle tracking applications. Moreover, efficient FONs coating was achieved by using a polymeric additive built from a long hydrophobic (PPO) and a short hydrophilic (PEO) segment and having a cationic head group able to interact with the highly negative surface of FONs. This electrostatically-driven interaction promotes both photoluminescence and two-photon absorption enhancement leading to an increase of two-photon brightness of about one order of magnitude. This opens the way to wide-field single particle tracking under two-photon excitation
Solvent-modified ultrafast decay dynamics in conjugated polymer/dye labeled single stranded DNA
Inhong Kim, Mijeong Kang, Han Young Woo, et al.
We have investigated that organic solvent (DMSO, dimethyl sulfoxide) modifies energy transfer efficiency between conjugated polymers (donors) and fluorescein-labeled single stranded DNAs (acceptors). In a mixture of buffer and organic solvent, fluorescence of the acceptors is significantly enhanced compared to that of pure water solution. This result can be attributed to change of the donor-acceptor environment such as decreased hydrophobicity of polymers, screening effect of organic solvent molecules, resulting in an enhanced energy transfer efficiency. Time-resolved fluorescence decay of the donors and the acceptors was modelled by considering the competition between the energy harvesting Foerster resonance energy transfer and the energy-wasting quenching. This enables to quantity that the Foerster distance (R0 = 43.3 Å) and resonance energy transfer efficiency (EFRET = 58.7 %) of pure buffer solution become R0 = 38.6 Å and EFRET = 48.0 % when 80% DMSO/buffer mixture is added.