Nanopartz Gold Nanorods

 

 

 

 

Composition

These bare gold nanorods are shipped in DI water with trace CTAB, trace poluymers, and no measurable residual chemicals. This guarantees little to no flocculation at 4°C storage and no wavelength shifting over time. 

Custom Formulation

Diameters 5, 10 nm, 25 nm, 40 nm, 50 nm, and 70 nm with resonances from 550nm to 2100nm are standard.  Other sizes are special order.  Please contact us.

Quantity

This product is available in 1mL and larger. For orders larger than 100mL, or for orders amounting over 10L per annum, please contact sales for quantity pricing.

Delivery

Standard sizes are in stock. Special order sizes are shipped in two weeks or less. All domestic shipments are sent Fed Ex Standard Overnight delivery, international Fed Ex Priority 2 day. No shipments on Fridays.

Conjugations

This product comes standard with CTAB. Options include PEI, PAH, PAA, Citrate, and Nanopartz non covalent charged polymers.

Shelf Life/Storage Temperature

This product is guaranteed for six months and should be stored at 4°C after opening. Care must be taken to only use sterile glassware when working with this product.

Toxicity

CTAB is known to be cytotoxic. All other conjugations are non-cytotoxic. This product has been sterilized and is biological free.

Sterilization

This product is sterilized.

The manufacturing method for these nanoparticles are based on our proprietary method. This invention allowed the first use of a reducing agent to be used at room temperature. Unlike citrate which is only a reducing agent at the boiling temperature of water - thereby quickly making non-monodisperse gold nanoparticles, our reducing agent works by slowing building nanoparticles from seed, atom by atom, over the course of up to hours. The result is a highly monodisperse product with unrivaled spherical shapes.

All of these "bare" particles are capped with ligands that are easily replaced with thiol and charge chemistries. We do not recommend using the carboxyl termination on our proprietary ligand as a conjugatable attachment.

Certifications

Every order comes with a Certification of Analysis that includes the following information. We use calibration traceable:

UV-VIS (Agilent 8453) for extinction and concentration measurements

NIR (Cary 500) for NIR extinction and concentration measurements

DLS (Malvern Nano ZS) for zeta potential measurement

ICP-MS (Varian 820-MS) for gold mass measurements

TEM (Phillips CM-100 100KV) for sizing

TN602 Storage and Handling

TN802 Photothermal Characteristics of Gold Nanorods

TNC01 Overview of Gold Nanorods

TNC02 Nanorod Crystallography

SDS Part # A12

Sole Source Advantages

I am having a really hard time centrifuging the nanorods without them crashing.  I want to conjugate and purify - what do you recommend?

Purification of the nanorods is no simple task.  That's why we developed our our conjugated nanorods with carboxyl, amine, biotin, and neutravidin terminations - to make it easy for any of your conjugations. For a published paper regarding conjugating the gold nanorods, refer Rostro-Kohanloo et. al, "The stabilization and targeting of surfactant-synthesized gold nanorods", Nanotechnology 20 (2009)( http://atmsp.whut.edu.cn/resource/pdf/11144.pdf)

We have bought some gold nanorods from you and we would like to know the thickness of the CTAB coating because we are interested in the interaction between these CTAB coated nanorods with the surrounding. Do you know the thickness of the CTAB coating?

CTAB forms a bilayer micelle on the nanorods.  If it is completely linear, then the bilayer thickness would be ~3nm.

I don't see any CTAB in your nanorod solution, even at 4 °C. Why not?

We have devised a method that removes most all of the CTAB in the solution, only leaving that necessary for the stability of the nanorods.

Your nanorods never shift wavelength and their extinctions are very stable in both intensity and wavelength. I thought that nanorods were notorious for shifting to lower wavelengths with time?

Like the method described above, not only do we remove the excess CTAB, we are also able to remove all the active components, leaving only stable nanorods.

Why are nanorods positive in charge? All of the spheres I've ever used are negative in charge?

The fact that CTAB is a micelle creates the + positive charge on the nanorod.

What does the term "bare" when applied to nanoparticles mean?

There are no such thing as completely "bare" nanoparticles that are stable long term. Ligands are used to stabilize gold nanoparticles. The key to a "bare" nanoparticle ligand is one that is lightly adsorbed and can be readily replaced through covalent, charge, or other types of bonds.

How do you size your nanorods?

We use a combination of TEM and UV VIS to correctly assign exact measurements and variance to the nanorods.

Do you really provide a TEM for my specific lot?

Yes, and not just for 5-10 particles, rather 50-100 are standard.

What is OD?

Optical Density (OD) is measured by UV-VIS. An Optical Density OD=1 corresponds to a transmission of 10% through a 1cm cuvette. Optical Density is a nice unit to use since Optical Densities correlate linearly to concentration. So an Optical Density of 1.2 is equal to 1.2 times the concentration of a gold nanoparticle solution that has an Optical Density of 1. We use OD and concentration interchangingly as it is easier to refer to a solution of OD=1 rather than 2.35e12 nanoparticles. For all spheres up to 200nm, OD=1 does refer to 0.05mg/mL.

What is PDI?

PDI refers to polydispersity index and is equal to the standard deviation of the particle sizes divided by the average size.

Why is your shelf life time so much longer for your proprietary gold nanoparticles when compared to citrate stabilized gold nanoparticles?

As opposed to citrate, our Nanopartz Carboxylic Acid capping agent is not a growth medium.

Are your proprietary gold nanoparticles interchangeable with citrate stabilized gold nanoparticles?

Yes. However, the user must be aware that in order to stabilize citrate gold nanoparticles, previous manufacturers used to add many stabilizing agents. Consequently for example to ionically attach ligands to gold nanoparticles required the chemist to "drive" the reaction by adding 10-1000 times greater concentrations of the ligand. This is no longer necessary with our gold nanoparticles.

"We are now using Nanopartz Oligo Functionalized Nanorods for all of our DNA Origami work, and we are getting very good results!"

Dr. Guillermo Acuna 
TU Braunschweig 
Institute of Physical and Theoretical Chemistry
AG Tinnefeld for NanoBioSciences

 

"I have used Nanopartz MUTAB coated gold nanorods and their concentrated bare spherical gold nanoparticles for electrospray applications and have found their products easy to use, and their technical support to be excellent.  The solutions have excellent stability over long periods of time and meet the promised specifications closely. Thanks Nanopartz, I look to continue to use your products for many years to come."

Ranganathan Gopalakrishnan 
PhD Student 
University of Minnesota

 

"We have been using Nanopartz bare Au nanorods and bare Au nanospheres for studying their individual intrinsic photoemission properties in vacuum. We have been extremely pleased with their cleanliness and uniformity."

Andrej Grubisic, PhD
Postdoctoral Fellow at University of Colorado at Boulder - JILA

"We have looked at many different gold nanoparticles samples from Nanopartz including spheres, rods, and microrods using single particle spectroscopy techniques and are extremely happy with the quality of the samples and the service provided by Nanopartz."

Stephan Link, PhD
Assistant Professor of Chemistry
Rice University

 

 

The manufacturing method for these nanorods are based on multiple patents and proprietary methods. The results are unparalleled monodispersity, scalability, and most important repeatability.

We possess the technology for single nanometer tuning of both the transverse and longitudinal dimensions.

All of these "bare" particles are capped with ligands that are easily replaced with thiol and charge chemistries. We do not recommend using the carboxyl termination on our proprietary ligand as a conjugatable attachment.

	Nanopartz Nanorod Technology	Other Technologies
Monodispersity	High	Low
Linewidths	Narrow	Broad
Wavelength shifting during storage	None	Large
High CTAB Concentrations (CTAB cloud)	None	Yes
SPR Wavelengths 550nm to 2100nm	Yes	600-1000nm
Small and Large Axial Diameters (5nm and 70nm)	Yes	No

 

• Diameters from 10nm to 50nm.
• NIR SPRs for diameters greater than 10nm.
• Wavelength accuracy better than 10 nm in many cases.
• Size monodispersity better than 10% CV
• Greater than 95% rods, less than 5% other shapes
• Available in aspect ratios from 1.4 to 17.5, resulting in extinctions from 550 to 1400 nm.
• CTAB concentration is reduced to < 10mM without adverse effects to the nanorods.
• Negatively charged coatings also available.
• Extremely stable. Shelf life is greater than one year.
• High anisotropy.
• High non-linear coefficients. Extremely efficient for frequency conversion.
• Near IR absorptions four orders of magnitude larger than quantum dots in the visible. Photothermal cross sections that leads to highly efficient optical to heat conversion.