Del Mar Photonics - Newsletter Fall 2010 - Newsletter Winter 2010 - Del Mar Photonics at Photonics West 2011

Del Mar Photonics featured customer presentation at Photonics West 2011

Inactivation of encephalomyocarditis virus and herpes simplex virus by using a visible femtosecond laser request a quote

Paper 7895-28 of Conference 7895
Date: Wednesday, 26 January 2011
Time: 12:10 PM 12:30 PM

Author(s): Shaw-Wei D. Tsen, Washington Univ. in St. Louis (United States); Kong-Thon Tsen, Arizona State Univ. (United States)


Recently, a variety of viral systems, including M13 bacteriophage, tobacco mosaic virus (TMV), human papillomavirus (HPV) and human immunodeficiency virus (HIV) have been shown to be inactivated by the irradiation of a near-infrared subpicosecond fiber laser. These experimental results indicated that the inactivation of viruses by an ultrashort pulsed laser might involve disruption of their protein coat through laser-induced excitation of large-amplitude acoustic vibrations. In this work, we report experimental results on the inactivation of both encephalomyocarditis virus (EMCV) and herpes simplex virus (HSV) by using a visible femtosecond laser derived from the second harmonic generation of a cw mode-locked Ti-sapphire laser system. The inactivation of these viral particles has been demonstrated to depend on the laser exposure time as well as laser power density. Possible mechanisms for the inactivation will be discussed.
 

Del Mar Photonics Trestles femtosecond Ti:Sapphire laser is used by researchers from Arizona State University to kill viruses and bacteria.
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The research is described in several publications including SPIE newsroom article:
http://spie.org/x18231.xml?ArticleID=...

K. T. Tsen, Shaw-Wei Tsen, Chih-Long Chang, Chien-Fu Hung, T.-C. Wu, B. Ramakrishna, and Juliann G. Kiang

A new technique for targeting viral capsids may be applicable to a wide variety of pathogens.
21 December 2007, SPIE Newsroom. DOI: 10.1117/2.1200711.0928

Most antiviral and antibacterial treatments are only partially successful in eliminating target pathogens and may raise problems associated with drug resistance, adverse events, and unwanted side effects. Although UV irradiation represents an alternative, it lacks selectivity, eliminating unwanted microorganisms but also damaging other structures while raising concerns over harmful mutations. New methods to circumvent these limitations are particularly desirable.

One experimental technique involves microwave absorption with a view to destroying microorganisms by exciting their vibrational states.1,2 But water, the basic environmental medium for most undesirable microorganisms, readily absorbs microwave energy in the range of 10-300GHz, which also happen to be the typical vibrational frequencies of viral capsids (shells).3,4 In general, it is extremely difficult to affect the vibrational energy of microorganisms. Overcoming this drawback will require, in place of microwave excitation, visible sources in which water is transparent.

To this end, we have employed a low-power visible femtosecond laser system. By exciting low-frequency vibrational modes of the viral capsid through impulsive stimulated Raman scattering (ISRS) to a high-energy state, we have succeeded in inactivating virus. We expect this method to be highly selective and applicable to any viral or bacterial system.

Optical excitation of coherent lattice or molecular vibrations through stimulated light scattering can be carried out either by focusing an intense laser into a medium with a Raman-active vibrational mode or by spatially and temporally overlapping two laser outputs that possess a suitable frequency difference. ISRS has been shown to be a viable method for producing large-amplitude vibrational modes, for both molecules in solution and lattice vibrations in solid-state systems.5 It has been used to excite coherent acoustic phonons in ethanol, malachite green and cresyl violet in ethanol,6 and coherent optical phonons in α-perylene crystal.7 In this process, the electric field from a femtosecond laser produces an impulsive force through induced polarization. This mechanical impact coherently excites Raman-active vibrational modes on the capsid. If the pulse width, spectral width, and intensity of the femtosecond laser are appropriately chosen, the vibrational modes can be excited to high-energy states that break the weak links and damage or destroy the capsid, leading to inactivation of the virus.

We have demonstrated this innovative and unconventional method with M13 bacteriophages, viruses that exclusively infect Escherichia coli.8,9 By using a very low power visible femtosecond laser with a wavelength of 425nm and a pulse width of 100fs, we showed that M13 phages became inactive when laser power density was greater than or equal to 50MW/cm2 (see Figure 1).

Figure 1. Inactivation of the M13 bacteriophage as a function of excitation laser power density.

Inactivation was determined by plaque counts and depended critically on pulse width as well as power density of the excitation laser. Figure 2(a) shows the M13 bacteriophages without, and Figure 2(b) with, laser irradiation. The M13 bacteriophage is a helix-shaped virus with a diameter of about 6nm and length of about 850nm. Disappearance of the wormlike images in Figure 2 indicates capsid disintegration.

Figure 2. Atomic force microscope image of M13 bacteriophage (a) without and (b) with laser irradiation.

Our findings thus suggest a new method for manipulating, controlling, and inactivating undesirable microorganisms while leaving sensitive mammalian cells unharmed. It also demonstrates how basic principles of impulsive coherent acoustic excitation using an ultrafast laser optical system can selectively alter viral function or inactivate viruses and, potentially, other microorganisms. Because acoustic capsid vibrations are usually of long wavelength, they are relatively insensitive to minor local changes, such as those due to mutations. Therefore, our approach may also be applicable to drug-resistant strains of microorganisms. Testing is under way. Finally, work in progress includes efforts to inactivate the human immunodeficiency virus (HIV) and disinfect the blood supply.

This work is supported by the National Science Foundation.

This video shows was taken during Trestles optimization and training visit.

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Other presentation about using lasers in virus related applications

Silicon-based photonic crystal nanocavities for label-free virus detection

Paper 7888-8 of Conference 7888
Date: Saturday, 22 January 2011
Time: 4:30 PM 4:45 PM

Author(s): Sudeshna Pal, Amrita R. Yadav, Univ. of Rochester (United States); Benjamin L. Miller, Univ. of Rochester Medical Ctr. (United States); Philippe M. Fauchet, Univ. of Rochester (United States)

The optical biosensing platform exploited in this study is a two-dimensional w1 photonic crystal (PhC) waveguide created by removing a central array of holes from the crystal periodic structure. A nanocavity when coupled to the w1 waveguide, allows light to be transmitted except at frequencies that correspond to the resonant mode of the cavity. This PhC nanocavity design is extremely sensitive and allows multiplexed detection of analytes on a single biosensing platform. The fabricated device has been tested with human papillomavirus (HPV) virus-like particles (VLPs) to study the sensor response in virus detection. Preliminary results show an average resonant red-shift of ~ 3 nm at high VLP concentrations with the device thus indicating successful detection of the VLPs.

LED-interferometric reflectance imaging sensor for label-free detection of nanoparticles

Paper 7888-16 of Conference 7888
Date: Sunday, 23 January 2011
Time: 11:15 AM 11:30 AM

Author(s): George Daaboul, Boston Univ. (United States); Priscilla F. Renda, Russell Graef, MITRE Corp. (United States); Abdulkadir Yurt, Xirui Zhang, Carlos Lopez, John H. Connor, Boston Univ. (United States); Grace M. Hwang, MITRE Corp. (United States); M. Selim Unlu, Boston Univ. (United States)

We report a simple wide-field phase imaging technique, LED-Interferometric Reflectance Imaging Sensor (LED-IRIS), that utilizes on-chip common path interferometry for real-time detection and sizing of low-index particles such as viruses. We demonstrate nanoparticle sizing from 70nm-200nm in diameter and also resolve hundreds of individual H1N1 viruses over a wide area in a single experiment. An immunoassay is being developed for specific-capture and detection of single H1N1 virus using various probes multiplexed on the same substrate. Approved for Public Release: 10-2641. Distribution Unlimited. 2010 The MITRE Corporation. All rights reserved.

MS2 bacteriophage as a delivery vessel of porphyrins for photodynamic therapy

Paper 7886-41 of Conference 7886
Date: Sunday, 23 January 2011
Time: 5:30 PM

Author(s): Brian A. Cohen, Alain E. Kaloyeros, Magnus Bergkvist, Univ. at Albany (United States)

We have selected the MS2 bacteriophage as a potential candidate for use as a nanoscale delivery vessel of photoactive compounds for site-specific photodynamic therapy. MS2 was chosen for two reasons: (1) a series of pores on the capsid exterior large enough to allow the PDT agents access to the interior and; (2) there is a 7 nm diameter void space inside the capsid large enough for the loading of hundreds of photoactive compounds. The research presented here investigates the reactive oxygen species photogeneration by a porphyrin encapsulated inside MS2.

Improved signal-to-noise detection of single virion using microcavities

Paper 7908-24 of Conference 7908
Date: Thursday, 27 January 2011
Time: 9:30 AM 9:50 AM

Author(s): Tao Lu, Univ. of Victoria (Canada) and California Institute of Technology (United States); Hansuek Lee, Tong Chen, Ji Hun Kim, California Institute of Technology (United States); Steven Herchak, Univ. of Victoria (Canada); Kerry Vahala, California Institute of Technology (United States)

Using a stable reference interferometer to monitor cavity resonance shift in real time, one can suppress the influence of laser jitter noise and achieve sub-femtometer precision of the resonance wavelength measurement. Using this technique, detection of Influenza A virion with signal-to-noise-ratio exceeding 30:1 has been demonstrated using a silica microtoroid as an ultra-high-Q microcavity sensor. Binding of polystyrene nanobeads with radii as small as 25nm is also studied.

Nano-LISA for in vitro diagnostic applications

Paper 7899-59 of Conference 7899
Date: Tuesday, 25 January 2011
Time: 8:45 AM 9:00 AM

Author(s): Saher M. Maswadi, Randolph D. Glickman, The Univ. of Texas Health Science Ctr. at San Antonio (United States); Norman Barsalou, William R. Elliott III, Naval Health Research Ctr. Detachment (United States)

We previously investigated the detection of pathogenic agents, utilizing laser spectrscopy and antibody-coupled gold nanorods (NR) as a contrast agent as a contrast agent specifically targeted to the antigen of interest. The Nano-LISA (Nanoparticle Linked Immunosorbent Assay) method has been adapted to detect three very common blood-borne viral infectious agents, i.e. human T-lymphotropic virus (HTLV), human immunodeficiency virus (HIV) and hepatitis-B (Hep-B). A working laboratory prototype of a Nano-LISA microplate reader-sensor has been assembled and has been tested with the model panel of the infectious agents. Thus, adequate detection sensitivity, as well as lack of non-specific cross-reaction between antigens, has been demonstrated for the OA microplate reader-sensor, and supports the use of Nano-LISA as a clinical in vitro diagnostic technique.

Integrated lab-on-a-chip: a combined sample preparation and PCR system as an ultrafast analytical tool for pathogen detection

Paper 7929-1 of Conference 7929
Date: Sunday, 23 January 2011
Time: 2:30 PM 3:00 PM

Author(s): Holger Becker, Nadine Hlawatsch, Richard Klemm, Claudia Gärtner, microfluidic ChipShop GmbH (Germany)

The overall aim is the realization of a reliable, ultrafast, and portable system for the identification of pathogens and other B-agents at the point of interest. PCR is the method to be used for the unambiguous identification of e.g. bacteria, and viruses. Miniaturization is the way to include the overall analysis process, from sample preparation to detection, on a microtiterplate-sized consumable device and to allow to carry out the analysis without the need for an equipped biological laboratory.

Integrated lab-on-a-chip: a combined sample preparation and PCR system as an ultrafast analytical tool for pathogen detection

Paper 7888-1 of Conference 7888
Date: Sunday, 23 January 2011
Time: 2:30 PM 3:00 PM

Author(s): Holger Becker, Nadine Hlawatsch, Richard Klemm, Claudia Gärtner, microfluidic ChipShop GmbH (Germany)

The overall aim is the realization of a reliable, ultrafast, and portable system for the identification of pathogens and other B-agents at the point of interest. PCR is the method to be used for the unambiguous identification of e.g. bacteria, and viruses. Miniaturization is the way to include the overall analysis process, from sample preparation to detection, on a microtiterplate-sized consumable device and to allow to carry out the analysis without the need for an equipped biological laboratory.

An automated wide-field, time-gated, optically sectioning, fluorescence lifetime imaging multiwell plate reader for high-content analysis of protein-protein interactions

Paper 7904-61 of Conference 7904
Date: Monday, 24 January 2011
Time: 5:30 PM

Author(s): Sunil Kumar, Imperial College London (United Kingdom); Dominic R. Alibhai, Imperial College London (United Kingdom) and Pfizer Group Ltd. (United Kingdom); Clifford B. Talbot, James A. Mcginty, Ian H. Munro, Yuriy Alexandrov, Anca Margineanu, Imperial College London (United Kingdom); Ted Murray, Frank Stuhmeier, Pfizer Group Ltd. (United Kingdom); Christopher W. Dunsby, Mark A. Neil, Paul M. W. French, Imperial College London (United Kingdom)

We describe an optically-sectioned FLIM multiwell plate reader applied to high content analysis and FRET that combines Nipkow microscopy with wide-field time-gated FLIM and acquires sectioned FLIM images in <10 s/well, requiring only ~11 minutes to read a 96 well plate. It has been applied to study the formation of immature HIV virus like particles (VLPs) in live cells by monitoring Gag-Gag protein interactions using FLIM FRET of HIV-1 Gag transfected with CFP or YFP. VLP formation results in FRET between closely packed Gag proteins, as confirmed by our FLIM analysis that includes automatic image segmentation.

Bioconjugation of ultra-high-Q optical microcavities for label-free sensing

Paper 7888-2 of Conference 7888
Date: Saturday, 22 January 2011
Time: 2:00 PM 2:15 PM

Author(s): Heather K. Hunt, Andrea M. Armani, The Univ. of Southern California (United States)

The development of label-free biosensors with high sensitivity and specificity is of significant interest for medical diagnostics and environmental monitoring, where rapid and real-time detection of antigens, bacteria, viruses, etc., is necessary. Ultra-high-Q optical microcavities are uniquely suited to sensing applications, but previous efforts in this area have focused on the development of the sensor itself. Here, we demonstrate a facile method to impart specificity to optical microcavities, without adversely impacting their optical performance. This work represents one of the first examples of non-physisorption-based bioconjugation of optical microtoroid resonators, which can be used for the label-free detection of biomolecules.

A novel evanescent field biosensor with an integrated photodetector array

Paper 7888-5 of Conference 7888
Date: Saturday, 22 January 2011
Time: 3:30 PM 4:00 PM

Author(s): Kevin L. Lear, Rongjin Yan, David S. Dandy, N. Scott Lynn, Richard A. Slayden, Luke C. Kingry, Colorado State Univ. (United States)

A label-free, evanescent field biosensor is implemented using SiNx/SiO2 optical waveguides in a conventional silicon integrated circuit manufacturing process. Rather than surface plasmon, interference, or resonance phenomena, the transduction mechanism relies on leaky-mode coupling to an array of photodetectors buried under the waveguide. Changes in surface refractive index locally modulate photocurrent, motivating naming the device a local evanescent array coupled (LEAC) sensor. Operation has been demonstrated using ~1 nm average thickness protein films as well as tuberculosis antigen and antibody capture probes. Preliminary investigations on virus detection are also reported as part of research to develop a multi-pathogen detection platform.

Plasmonic enhanced femtosecond-laser optoporation and transfection of human melanoma cells

Paper 7925-17 of Conference 7925
Date: Sunday, 23 January 2011
Time: 4:30 PM 4:50 PM

Author(s): Judith Baumgart, Ecole Polytechnique de Montréal (Canada); Laure Humbert, Royal Victoria Hospital (Canada); Bastien St.-Louis Lalonde, Ecole Polytechnique de Montréal (Canada); Jean-Jaques Lebrun, Royal Victoria Hospital (Canada); Michel Meunier, Ecole Polytechnique de Montréal (Canada)

Melanoma is a complex and aggressive cancer and over the past 50 years, its incidence in most developed countries has increased faster than any other cancer. We have investigated the use of a femtosecond (fs) laser to create localized small holes in the membranes of targeted cells to develop a virus-free technique to allow transfer of genetic material for treating these cancer cells with high efficiency and minimal collateral damage. This plasmonic enhanced fs laser process is efficient and highly selective with high cell viability, up to 90%. An optimum perforation rate with efficient molecule uptake was found for different types of gold nanostructures, spherical (100-200nm) and rod shaped (10x40nm).

Application of field-modulated birefringence and light scattering to biosensing

Paper 7888-24 of Conference 7888
Date: Sunday, 23 January 2011
Time: 4:15 PM 4:30 PM

Author(s): Louis H. Strong, Daniel B. Hall, Clark Edson, Gyula Varadi, Radiation Monitoring Devices, Inc. (United States)

Superparamagnetic nanoparticles (NPs) coated with surface ligands are shown to be an effective means to impart magnetic field modulation to optical signals from targeted receptor complexes. The resulting temporally modulated signals can be used for a number of important high throughput applications in bio-sensing including: detecting (weaponized) viruses, screening recombinant libraries of proteins, identifying pathogenic conversions of microbes, and monitoring gene amplification. We compare the results of two dynamic methods of measuring target binding to NPs: birefringence and field modulated light scattering (FMLS). These measurements reflect complementary manifestations of NP alignment (orientation) and de-alignment (relaxation) dynamics. Birefringence originates from the specific crystalline properties of a small subset of paramagnetic NPs (for example, maghemite ) when oriented in a magnetic field. Upon quenching the field, it decays at a rate exhibiting the Debye-Stokes-Einstein rotational relaxation constant of the target-NP complex. Birefringence relaxation reflects the particle dynamics of the mixed suspension of NPs, with signal components weighted with respect to both free and complexed NP size distributions. FMLS relaxation signals, on the other hand, originate predominately from the inherent optical anisotropy of the target complexes, show little contribution from non-complexed NPs, and provide a more direct and accurate method for determining target receptor concentrations. Several illustrations of the broad range of applications possible using these dynamic measurements and the kind of information to be derived from each detection modality will be discussed.

Application of field-modulated birefringence and light scattering to biosensing

Paper 7929-24 of Conference 7929
Date: Sunday, 23 January 2011
Time: 4:15 PM 4:30 PM

Author(s): Louis H. Strong, Daniel B. Hall, Clark Edson, Gyula Varadi, Radiation Monitoring Devices, Inc. (United States)

Superparamagnetic nanoparticles (NPs) coated with surface ligands are shown to be an effective means to impart magnetic field modulation to optical signals from targeted receptor complexes. The resulting temporally modulated signals can be used for a number of important high throughput applications in bio-sensing including: detecting (weaponized) viruses, screening recombinant libraries of proteins, identifying pathogenic conversions of microbes, and monitoring gene amplification. We compare the results of two dynamic methods of measuring target binding to NPs: birefringence and field modulated light scattering (FMLS). These measurements reflect complementary manifestations of NP alignment (orientation) and de-alignment (relaxation) dynamics. Birefringence originates from the specific crystalline properties of a small subset of paramagnetic NPs (for example, maghemite ) when oriented in a magnetic field. Upon quenching the field, it decays at a rate exhibiting the Debye-Stokes-Einstein rotational relaxation constant of the target-NP complex. Birefringence relaxation reflects the particle dynamics of the mixed suspension of NPs, with signal components weighted with respect to both free and complexed NP size distributions. FMLS relaxation signals, on the other hand, originate predominately from the inherent optical anisotropy of the target complexes, show little contribution from non-complexed NPs, and provide a more direct and accurate method for determining target receptor concentrations. Several illustrations of the broad range of applications possible using these dynamic measurements and the kind of information to be derived from each detection modality will be discussed.

 

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