Fluorophore Labeled Gold Nanoparticles for Cell Uptake

 

 

Ligand	Description	Zeta	Space to Add fluorophores or Payload	Covalent?	Cell uptake Efficiency
CU	Nanopartz Proprietary Cell Uptake	+10	Yes	Yes	High
MUTAB	Positive charged, covalent attached (11-Mercaptoundecyl)-N N N-trimethylammonium bromide	+35	No	Yes	Medium
MTAB	Positive charged, covalent attached (16-mercaptohexadecyl)tri-methylammonium bromide	+40	No	Yes	Medium

 

Wavelength	Name	Excitation (nm)	Emission (nm)	Ext. Coef	QY
405	AF405	402	421
	Dy405	400	420
488	FITC	494	518	70000
	Dy488	493	518	70000
	AF488	490	525
514	NPZ514	520	540
532	Rhodamine	535	575
550	Cy3	555	570	150000	0.31
	Dy550	562	576
	AF555	555	580
600	Cy3.5	591	604	116000	0.35
	Dy594	593	618
	AF594	590	617
	Texas Red	592	614
650	Cy5	646	662	250000	0.2
	Dy 650	652	672
	AF647	650	665

 

Composition

These gold nanoparticles are shipped in  DI water with no measurable residual reactants.

Custom Formulation

Diameters 1.8nm to 3nm.  Larger sizes may reduce cell uptake efficiency. Please contact us.

Quantity

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

Introductory Kits

None are currently available.

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 except for dried particles. Saturday shipping available for extra charge.

Functionalization

This product comes with a number of Frag' IgG functionalizations with a complete range of fluorophore choices.

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

This product is known to be noncytotoxic. This product has been sterilized and is biological free.

Sterilization

This product is sterilized.

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

TN801 UV VIS to Determine Size and Concentration

SDS Part # PNU11

Sole Source Advantages

CU Cell Uptake Procedure

What makes these nanoparticles so efficient at cell uptake?

It is well known that the strongly positive MUTAB and MTAB ligands lead to efficient cell uptake. Unfortunately because of their construct, there is no way to add antibodies, oligos, fluorophore or any other payloads. The Nanopartz Cell Uptake polymer resolves that issue.

Why are you able to get high efficiency cell uptake with such large gold nanoparticles?

Two reasons: 1) the monodispersity of our gold nanoparticles and 2) the ligand design construct. Our ligand design has reduced the overall size of the construct, making it more efficient at nucleus uptake.

How do you size your gold nanoparticles? Does the size include the capping agent?

We use three methods to specify our gold nanoparticles; TEM, UV VIS, and DLS. Each has its own advantages and disadvantages, and we use a weighted system to take advantage of each methods strengths. In the end, we place the strongest weight to the TEM method, particularly since we use samples sizes greater than 50 particles for each lot.

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.

"We were previously making our own gold nanoparticles using the commonly used technique of citrate reduction of Au(III). The colloids generated are broadly polydisperse, and we were concerned that our application of these particles in immuno-gold labeling of cells for optical coherence microscopy (OCM) would be utilizing only the large diameter tail of the distribution. We purchased the sampler package of NanoPartz gold spheres (30 nm, 50 nm, 70 nm, 90 nm) and examined each size carefully with dynamic light scattering, OCM, and spectrophotometry. Our measurements indicated diameters a couple nanometers larger than specifications (a result of measurements on the fully hydrated state?), and remarkable monodispersity - within specs. It is clear to us now that our early immuno-gold results were dominated by the largest diameter spheres of our early colloids. We are delighted by the NanoPartz monodisperse preparations and recommend them strongly!"

Dr. Richard C. Haskell 
Professor of Physics & Director of Physics Clinic 
Physics Department 
Harvey Mudd College

"The scientists at Nanopartz have developed a line of colloidal gold nanorods with extremely high monodispersity in size, shape, and mass. The surfactant layer is highly stable and readily displaced for biofunctionalization. In every test, in vitro and in vivo, these materials have exceeded our expectations."

Geoffrey A. von Maltzahn
NSF and Whitaker Graduate Fellow
Harvard-MIT Division of Health Sciences and Technology
Laboratory for Multiscale Regenerative Technologies

 

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.

	Nanopartz™Accurate™ Spherical Gold Nanoparticles	Other Technologies
Monodispersity	High (<2%)	Low (>15%)
Size Accuracy	High (+/-2nm)	Low
Linewidths	Narrow	Broad
Storage lifetime	Years	6 months at 4C
Ability to ligand exchange	Easy	More difficult

 

• Highly accurate and monodisperse in size, shape, and batch to batch uniformity.
  • Monodisperse sizes and shapes leads to better standards for electron microscopy and other diagnostics.
• Accurate to +/- 2 nm in diameter.
  • More accurate sizing makes for better SPR matching for Surface Enhanced Raman Labels.
• Size monodispersity better than 4% CV for many sizes.
  • Monodisperse sizes and shapes leads to better Resonance Light Scattering labels in sensitivity and multiplexing
• Greater than 99.9% spheres.
• Carboxylic acid capping agent is reduced to < 0.1% without adverse effects to the spheres.
  • Reduced number of additives improves binding to antibodies, receptors, ligands and DNA.
• Extremely stable.  Shelf life is greater than one year.  May be stored at room temperature for extended periods.
• The light scattering power of a 60 nm gold particle is equivalent to ~5 X 10⁵ fluorescein molecules.
• Accurate™ SGNPs do not photobleach.
  • No photobleaching means better diagnostic labels with the ability to archive.
• Light scatter can be detected by the unaided eye at particle concentrations as low as 10^-15 M (femtomolar) in suspension and as low as 0.005 particles/m² on a transparent surface.
  • 10⁵ better scattering power than fluorescein means lower limits of detection with simpler instrumentation.
• Individual gold nanoparticles can be seen by eye in an inexpensive student microscope with simple dark field illumination allowing for very sensitive and inexpensive particle counting assays.
• Different sized particles scatter different colors of light and therefore can be used as multicolor multiplexed labels.
• Facile conjugations allow for coating of antibodies, receptors, ligands, DNA without affecting their light scattering properties.
• Slightly negatively charged (reduced aggregation).
• Facile synthesis.  Gold chemistry is well known.
• No known cytotoxicity