Bio-Synthesis provides custom conjugation of nanogold, undecagold or colloidal gold
to primary antibodies, peptides, protein, oligonucleotides, small moelcuels, or
other biomolecule. Relying on a state-of-the art chemial biology facilities and
over 30 years of combine experience in providing high quality bioconjugate complexes,
each custom colloidal gold conjugation project is metriculously monitored according
to Bio-Synthesis's stringent quality assurance and quality control standard that
are fully backed up by an bioanalytical laboratory.
Gold nanoparticles are incorporated into numerous technologies and applications.
Some of the most common gold nanoparticle applications are ideal for:
The use of Bio-Synthesis's unique expertise in bioconjugation chemistries, we ensures
high quality conjugates are produced.
Contact our Technical Service Center at 800.220.0627 or contact
us online with your detail project specifications, a project manager will
be assigned to help you with design and develop an appropreate synthetic method
for your specific needs.
Sample Submission Requirement:
Biomolecule supplied by customers should be sufficiently pure. Please provide 3
mgs of puriifed lyophilized antibody (or your protein) with the necessary data for
purity assessment. Commercial available biopolymers can be supplied by customers
or synthesize or ordered through Bio-Synthesis.
Price: Price varied based on project specifications. Price does
not includes cost of small molecule or biopolymer which requireed to be supplied
by customer or order through Bio-Synthesis from a commercial vendor. Some of the
small molecules are commerically available in an activated form. For non-active
molecules, Bio-Synthesis can assit with the design and, if deemed necessary, biopolymer
modification to introduce additional functional groups and extra linkers.
Please contact us for a quote.
Discount: 15 % discount price applies to additional conjugates
ordered at the same time.
Protein/Antibody-Gold Nanoparticles Conjugation
Due to variations in affinity between diferrent proteins and the gold nanoparticle
surface, there is no guaranteed final volume of product. An average yield of 10
ml of your protein-gold nanoparticle conjugate is 3 ODs. This amound woudl be enough
to be probe 100 dot blot strps using 15 ml of a 1:100 diluted conjugate per strip.
Oligonucleotide-Gold Nanoparticle Conjugation
Oligonucleotide length and sequence might influence final yield of gold nanoparticle
conjugates, an average yield is 1 OD in 30 ml of oligonucleotide-gold conjugates.
Chemistry: Coupling of preactivated small molecule and biomolecule
with chemical reactive groups such as Amine reaction with NHS or other active esters.
Sulfhydryl reaction with maleimide or alkyl halide containing compounds.
Service Specification: After standard desalting, or purification,
a small percent of heterogeneous products containing single or multi-site conjugate
per molecule may exist.
Material: nanogold, undecagold or colloidal gold size of your choice
Procedure: After labeling, final conjugates must first be isolated
from excess or unreacted reagent by gel filtration or dialysis. In many cases, simple
dialysis may suffice to remove unreacted reagent from the reaction solution. Additional
purification technique such as gel filtration chromatography may also be used to
either remove excess reagent or isolate and characterized the cross-linked product.
With exception of dialysis, if the protein/antibody is significantly larger (>3-fold)
than the modifying or coupling reagent. For reagents (mostly protein and other biological
molecules) that are similar in size or larger than the antibody, one must resort
to other purification techniques such as affinity chromatography, ion-exchange chromatography,
and hydrophobic interaction chromatography.
The conjugates were characterized using UV–visible (UV/Vis) absorption spectroscopy.
Transmission electron microscopy (TEM) and dynamic light scattering (DLS and the
biological activities of the conjugated products were also assessed using an immunoassay
format and electrochemical measurements with an additional fee.
Visit our literature vaults for more references and citings.
For us to better understand your customized project, please complete our Bioconjugation Service Questionnaire. The more our chemists understand your project needs, the more accurate feedback we will be able to provide you. Providing us with your project details will enable us to recommend the best reagents to use for your own project. The most useful and readily available tools for bioconjugation projects are cross-linking reagents. A large number of cross-linkers, also known as bifunctional reagents, have been developed. There are several ways to classify the cross-linkers, such as the type of reactive group, hydrophobicity or hydrophilicity, and the length of the spacer between reactive groups. Other factors to consider are whether the two reactive groups are the same or different (for example, heterobifunctional or homobifunctional reagents), whether the spacer is cleavable, and whether the reagents are membrane permeable or impermeable. The most accessible and abundant reactive groups in proteins are the ϵ-amino groups of lysine. Therefore, a large number of the most common cross-linkers are amino selective reagents, such as imidoesters, sulfo-N-hydroxysuccinimide esters, and N-hydroxysuccinimide esters. Due to the high reactivity of the thiol group with N-ethylmaleimide, iodoacetate and a-halocarbonyl compounds, new cross-linkers have been developed that contain maleimide and a-carbonyl moieties. Usually, N-alkylmaleimides are more stable than their N-aryl counterparts.
In addition to the reactive groups on the cross-linkers, a wide variety of connectors and spacer arms have also been developed. The nature of the spacer arm, and also the length, play an important role in the functionality. Longer spacer arms are generally more effective when coupling large proteins or those with sterically protected reactive side-chains. Other important considerations are the hydrophobicity, hydrophilicity, and the conformational flexibility. Long aliphatic chains generally fold on themselves when in an aqueous environment, which makes the actual distance spanned by such linker arms less than expected. Instead, spacers that contain more rigid structures (for example, aromatic groups or cycloalkanes) should be used. These structures, however, tend to be very hydrophobic which could significantly decrease the solubility of the modified molecules or even modify some of their properties. In such cases, it is recommended to choose a spacer that contains an alkylether (PEO) chain. Bio-Synthesis offers several cross-linkers with PEO chains, such as thiol-binding homobifunctional reagents, heterobifunctional based, and their derivatives.
Once the project scope has collected, we will provide an appropriate quotation within 3-5 days. Orders can be placed with either a PO (Purchase Order) or credit card. We accept POs and major credit cards ( ). Your credit card will be billed under 'Bio-Synthesis, Inc.' Click here to download our credit reference form. For international orders, we must apply the full charge at the time of the order is placed. In the unlikely event that any given order cannot be filled, our guarantee will take the form of a full refund.