Del Mar Photonics - Newsletter Fall 2010 - Newsletter Winter 2010
Del Mar Photonics is involved in research of CNTs, graphene nanoplatelets and graphene materials, develops advanced multifunctional materials for variety of applications as well as research instrumentation for characterization of the above.
Carbon nanotubes form ultrasensitive biosensor to detect proteins
Sunday, June 27, 2010
A cluster of carbon nanotubes coated with a thin layer of protein-recognizing
polymer form a biosensor capable of using electrochemical signals to detect
minute amounts of proteins, which could provide a crucial new diagnostic tool
for the detection of a range of illnesses, a team of Boston College researchers
report in the journal Nature Nanotechnology.
The nanotube biosensor proved capable of detecting human ferritin, the primary
iron-storing protein of cells, and E7 oncoprotein derived from human
papillomavirus. Further tests using calmodulin showed the sensor could
discriminate between varieties of the protein that take different shapes,
according to the multi-disciplinary team of biologists, chemists and physicists.
Molecular imprinting techniques have shown that polymer structures can be used
in the development of sensors capable of recognizing certain organic compounds,
but recognizing proteins has presented a difficult set of challenges. The BC
team used arrays of wire-like nanotubes approximately one 300th the size of a
human hair coated with a non-conducting polymer coating capable of recognizing
proteins with subpicogram per liter sensitivity.
Central to the function of the sensor are imprints of the protein molecules
within the non-conducting polymer coating. Because the imprints reduce the
thickness of the coating, these regions of the polymer register a lower level of
impedance than the rest of the polymer insulator when contacted by the charges
inherent to the proteins and an ionized saline solution. When a protein molecule
drops into its mirror image, it fills the void in the insulator, allowing the
nanotubes to register a corresponding change in impedance, signaling the
presence of the protein, according to co-author Dong Cai, an associate research
professor of Biology at BC.
The detection can be read in real time, instead of after days or weeks of
laboratory analysis, meaning the nanotube molecular imprinting technique could
pave the way for biosensors capable of detecting human papillomavirus or other
viruses weeks sooner than available diagnostic techniques currently allow. As
opposed to searching for the HPV antibody or cell-mediated immine responses
after initial infection, the nanotube sensor can track the HPV protein directly.
In addition, no chemical marker is required by the lebel-free electrochemical
detection methods.
"In the case of some diseases, no one can be sure why someone is ill," said Cai.
"All that may be known is that it might be a virus. At that time, the patient
may not have detectable serum antibodies. So at a time when it is critical to
obtain a diagnosis, there may not be any traces of the virus. You've basically
lost your chance. Now we can detect surface proteins of the virus itself through
molecular imprinting and do the analysis."
Carbon-nanotubes as Ultrafast Photodetectors
Del Mar Photonics featured customer Bruce Weisman. Professor Weisman ordered Trestles Ti:Sapphire laser with built-in DPSS pump laser.
Professor Weisman wrote: Our applications are for carbon nanotube excitation, mostly with a cw beam but in some experiments with mode-locked pulses.
Del Mar Photonics offered Trestles Ti:Sapphire model with both CW and
femtosecond modes of operation.
Detailed laser specifications are as follows (request
a quote):
Trestles Ti:Sapphire laser with built-in DPSS pump laser
Ti:Sapphire oscillator having a tuning range of 710-920 nm;
Output power: 30mW (@3W pump, in the whole range);
Spatial mode: TEMoo;
Polarization: linear horizontal;
Repetition rate: 80 MHz;
Pulse duration: <100 fs
Electronic starter with TTL output for mode-locked mode
observation. Output mirrors included.
USB-controlled tuning slit for wavelength tuning
3BRF-TM 3-plate BRF for CW lasers (step motor controlled tuning)
Provides CW tuning and 40 GHz linewidth of the Trestles fs
lasers in CW mode; output power @700 nm - >50 mW (3W pump)
3 W pump DPSS laser with control and power supply unit
Power: 3 W
Wavelength: 532 nm
Beam size: 2.0 mm
Spatial mode: TEM00
Bandwidth: 30 GHz
Divergence: 0.4 mrad
M squared: < 1.1
Power stability: < 0.4 % RMS
Noise: < 0.4% RMS
Noise bandwidth: 1 Hz - 6 MHz
Pointing stability: < 2 microrads/C
Polarization ratio: 100:1
Polarization direction: horizontal
Coherence length: < 1 cm
Beam angle: < 1 mrad
Umbilical length: 1.5 m
Warm-up time: 10 min
R. Bruce Weisman Professor of Chemistry
Research Statement
Dr. R. Bruce Weisman and his group investigate the spectroscopy and photophysics
of fullerenes and carbon nanotubes. All of these are closed nanoscopic
structures formed from carbon atoms. Fullerenes, such as C60, C70, and their
chemical derivatives, have unusual molecular properties that cause interesting
behaviors following the absorption of light. Time-resolved absorption and
emission methods are used to study radiationless decay, photochemical reactions,
and
Selected Publications
R. Bruce Weisman and Shekhar Subramoney "Carbon Nanotubes." Interface (Summer,
2006): 42-46.
J. P. Casey, S. M. Bachilo, C. H. Moran, and R. B. Weisman "Chirality-Resolved
Length Analysis of Single-Walled Carbon Nanotube Samples through Shear-Aligned
Photoluminescence Anisotropy." ACS
J. P. Casey, S. M. Bachilo, and R. B. Weisman "Efficient Photosensitized
R. B. Weisman "Optical Spectroscopy of Single-Walled Carbon Nanotubes."
Contemporary Concepts of Condensed Matter Science. Carbon Nanotubes: Quantum
Cylinders of Graphene, 3 (2008): 109-133.
D. A. Tsyboulski, E. L. Bakota, L. S. Witus, J.-D. R. Rocha, J. D. Hartgerink,
and R. B. Weisman "Self-Assembling Peptide Coatings Designed for Highly
Luminescent Suspension of Single-Walled Carbon Nanotubes." J. Am. Chem. Soc.,
130 (2008): 17134-117140.
C. D. Doyle, J.-D. R. Rocha, R. B. Weisman, and J. M. Tour "Structure-dependent
Reactivity of Semiconducting Single-Walled Carbon Nanotubes with Benzene
Diazonium Salts." J. Am. Chem. Soc., 130 (2008): 6795-6800.
D. A. Tsyboulski, S. M. Bachilo, A. B. Kolomeisky, and R. B. Weisman
"Translational and Rotational Dynamics of Individual Single-Walled Carbon
Nanotubes in Aqueous Suspension." ACS
Robert F. Curl and R. Bruce Weisman "Biography of Richard Errett Smalley." J.
Phys. Chem. C, 111 (2007): 17653-17655.
Christopher J. Gannon, Paul Cherukuri, Boris I. Yakobson, Laurent Cognet, John
S. Kanzius, Carter Kittrell, R. Bruce Weisman, Matteo Pasquali, Howard K.
Schmidt, Richard E. Smalley, and Steven A. Curley "Carbon Nanotube-enhanced
Thermal Destruction of Cancer Cells in a Noninvasive Radiofrequency Field."
Cancer, 110 (2007): 2654-2665.
Laurent Cognet, Dmitri A. Tsyboulski, John-David R. Rocha, Condell D. Doyle,
James M. Tour and R. Bruce Weisman "Stepwise Quenching of Exciton Fluorescence
in Carbon Nanotubes by Single Molecule Reactions." Science, 316 (2007):
1465-1468.
Presentations
"Quantitative Analysis of Bulk SWCNT Samples using Near-IR Fluorimetry,” Focus
Session on Development of Purity Evaluation Criteria and Quality Assurance
Standards for Carbon Nanotubes,." Materials Research Society Meeting, Boston,
Massachusetts. (November 30, 2008)
"Near-infrared Fluorescence of Single-Walled Carbon Nanotubes: a
"Single-walled Carbon Nanotubes: Physical Properties and Biomedical
Applications." Howard Hughes Medical Institute Summer Lecture Series,
"Near-IR Fluorescence of Single-Walled Carbon Nanotubes: A
"Qualitative and Quantitative Analysis of Bulk SWNT Samples using Near-IR
Fluorimetry." Workshop on Metrology, Standardization, and Industrial Quality of
Nanotubes, Montpelier, France. (June 28, 2008)
Editorial Positions
Associate Editor, Applied Physics A, Springer-Verlag,, (2008).
Theses
Paul Cherukuri, Ph.D. "Biomedical Studies of Single-Walled Carbon Nanotubes
Using Near-Infrared Fluorescence." (2007).(Thesis or Dissertation Director)
Dmitry Tsyboulski, Ph.D. "Spectroscopic and Optical Imaging Studies of Fullerene
Complexes and Single-Walled Carbon Nanotubes." (2006).(Thesis or Dissertation
Director)
Eric Booth,
Awards
Elected Fellow, American Physical Society. (2008).
Paul Frison Accelator Award for Applied NanoFluorescence, Houston Business
Journal. (2007).
Institute of Physics in Ireland Lecturer, . (2005).
Del Mar Photonics - Newsletter Fall 2010 - Newsletter Winter 2010
Del Mar Photonics is involved in research of CNTs, graphene nanoplatelets and graphene materials, develops advanced multifunctional materials for variety of applications as well as research instrumentation for characterization of the above.
We currently we can offer:
1) Graphene nanoplatelets: the stack of multi-layer graphene sheets with high
aspect ratio, diameter: 0.5-20 µm,
thickness: 5-25 nm.
2) Graphene materials: Graphene Powder, Graphene Oxide Powder, Graphene
Suspension.
3) Carbon Nanotubes.
Contact our application team to discuss your requirements for high-performance nanocomposite materials, display materials, sensing materials, ultracapacitors, batteries, energy storage and other area to improve electrical, thermal, barrier, or mechanical properties by using low-cost nano-additive.
Graphene nanoplatelets are the stack of multi-layer graphene sheets including platelet morphology, with characteristics as follows:
| Physical Properties | |||||
| Diameter | Thickness | Specific Surface Area | Density | Electrical Conductivity | Tensile Strength |
| 0.5 - 20 µm | 5 - 25 nm | 40-60 m2/g | ~2.25 g/cm3 | 8000-10000 S/m | 5 GPa |
| Bulk Characteristics | ||||
| Appearance | Carbon content | Bulk density | Water Content | Residual impurities |
| A black and grey powder | >99.5% | ~0.30 g/ml | <0.5 wt% | <0.5 wt% |
Request a quote for graphene nanoplatelets
Applications:
The high performance composite additives in PPO, POM, PPS, PC, ABS,
PP, PE, PS, Nylon and rubbers.
To improve composite tensile strength, stiffness, corrosion resistance, abrasion
resistance and anti-static and lubricant properties.
Mechanical properties modifications.
Conductivity modification.
Fuel tank coating.
In electronic enclosures add electrical conductivity to polymers at low
densities of 3 to 5 wt%.
Adding EMI or RFI shielding capabilities to a variety of polymers.
Automotive parts: a composite with nanoplatelets can be painted
electrostatically, thereby saving costs.
Aerospace: graphite has long been used in aerospace composites. Nanoplatelets
can be combined with other additives to reinforce stiffness, add electrical
conductivity, EMI shielding, etc.
Appliances: fortified polymers provide superior thermal and electrical
conductivity, thereby saving the costs of separate heat dissipation mechanisms.
Sporting goods: graphite-based composites are stronger and stiffer and lighter
than comparable materials.
Coatings and paints: graphene nanoplatelets can be dispersed in a wide variety
of materials to add electrical conductivity and surface durability.
Batteries: graphene nanoplatelets increase the effectiveness of Lithium-ion
batteries when used to formulate electrodes.
Fuel cells: both bi-polar plate and electrode efficiencies can be improved.
Del Mar Photonics develops advanced instrumentation for research of CNTs, graphene nanoplatelets and graphene materials including lasers for broadband spectroscopy, femtosecond transient absorption and fluorescence measurements.
T&D Scan high
resolution Laser Spectrometer based on broadly tunable CW laser
CW single-frequency ring Dye laser
Beacon Femtosecond Optically Gated Fluorescence Kinetic Measurement System
New Hatteras femtosecond transient
absorption system
Photon Scanning Tunneling Microscope
Product Data Sheets
Del Mar Photonics Product brochures - Femtosecond products data sheets (zip file, 4.34 Mbytes) - Del Mar Photonics
Send us a request for standard or custom ultrafast (femtosecond) product
Pulse
strecher/compressor
Avoca SPIDER system
Buccaneer femtosecond
fiber lasers with SHG Second Harmonic Generator
Cannon Ultra-Broadband Light
Source
Cortes Cr:Forsterite
Regenerative Amplifier
Infrared
cross-correlator CCIR-800
Cross-correlator Rincon
Femtosecond Autocorrelator
IRA-3-10
Kirra Faraday Optical Isolators
Mavericks femtosecond
Cr:Forsterite laser
OAFP optical attenuator
Pearls femtosecond fiber laser
(Er-doped fiber, 1530-1565 nm)
Pismo pulse picker
Reef-M femtosecond scanning
autocorrelator for microscopy
Reef-RTD scanning
autocorrelator
Reef-SS single shot
autocorrelator
Femtosecond Second Harmonic Generator
Spectrometer ASP-100M
Spectrometer ASP-150C
Spectrometer ASP-IR
Tamarack and Buccaneer
femtosecond fiber lasers (Er-doped fiber, 1560+/- 10nm)
Teahupoo femtosecond Ti:Sapphire regenerative amplifier
Femtosecond
third harmonic generator
Tourmaline femtosecond fiber
laser (1054 nm)
Tourmaline TETA Yb
femtosecond amplified laser system
Tourmaline Yb-SS
femtosecond solid state laser system
Trestles CW Ti:Sapphire
laser
Trestles femtosecond
Ti:Sapphire laser
Trestles Finesse
femtosecond lasers system integrated with DPSS pump laser
Wedge Ti:Sapphire multipass amplifier