Bio-Synthesis has many years of experience in protein conjugation and modification through
chemical conjugation of oligonucleotides, proteins, toxins, bifunctional ligands,
haptens, fluorophores, and metal chelates for radio-isotope labeling. Our expertise,
however, is not only limited to protein modification and conjugation—we also perform
in-house recombinant protein expression. We offer the best quality protein bioconjugates
in the industry by implementing a state-of-the art gene synthesis platform and expertise
in providing high quality nucleic acid bioconjugate reagents. Gene-to-Protein
Expression, Modification and Conjugates produced at Bio-Synthesis have
substantial purity. Each protein-biopolymer conjugate is meticulously monitored
and controlled according to our stringent quality assurance and quality control
standards. QA (quality assurance) procedures are also followed independently to
double guarantee the high quality of every delivered peptide. The Bio-Synthesis
Total Quality Management System (TQM) has been successfully upgraded to fully comply
with ISO 9001:2008 regulations
Bio-Synthesis, leader in providing custom protein expression services as well as
protein modification and bioconjugation with target molecule of your choice. We
are devoted to delivering affordable peptide-biopolymer hybrid complexes, and offer
comprehensive modification and labeling options to be used for life science research,
diagnostics, and drug discovery.
Over the decades, we have accumulated a continually growing portfolio of peptide
modification and conjugation services. If you can't find what you want, contact
our National Customer Service Center at 800.220.0627, or contact
us online with your detailed project descriptions.
As each conjugation is unique, our support team will work closely with each client
to identify their objective and determine proper coupling chemistry. As we are the
experts in protein bioconjugation techniques, Bio-SynthesisI can provide a properly
conjugated product quickly and efficiently.
Chemistry: Coupling of preactivated small molecule and biomolecule
with chemical reactive groups such as amine, thiol, carboxylate, hydroxyl, aldehyde
and ketone, active hydrogen, photo-chemical and cycloaddition reactions, zero-length
cross-linking, homobifunctional, heterobiofunctional, or multifunctional cross-linking
chemistries, denrimer and dendrons, and cleavable reagent systems.
Some commonly used cross-linking reagents include:
Service Specification: After standard desalting, or purification,
a small percent of heterogeneous products containing single or multi-site conjugate
per molecule may exist.
Procedure: All custom synthesis of biomolecules, modification,
or bioconjugation services are manufactured under strict quality control processes.
Analytical HPLC and MS analyses are performed in every development cycle. Final
target conjugates must first be isolated from excess or unreacted reagent. In many
cases, simple dialysis removes unreacted reagent from the reaction solution. Additional
purification such as stirred cell filtration, tangential flow filtration (TFF),
or gel filtration chromatography may also be used to either remove excess reagent
or to isolate and characterize the cross-linked product with an additional fee.
For reagents that are similar in size or larger than the antibody (mostly protein
and other biological molecules), other purification techniques such as affinity
chromatography, ion-exchange chromatography, and hydrophobic interaction chromatography.
The cross-linked target molecule may then be further characterized by biochemical
or biophysical techniques. Once the product has been purified, it may be subject
to various characterization methods including spectrometric (MALDI-TOF, ESI, LC-MS),
fluorescence, electrophoresis, and immunochemical, biochemical, and enzymatic analysis.
QC (quality control) and QA (quality assurance) procedures are also followed independently
to ensure the highest quality possible of every delivered conjugate. Moreover, our
dedicated technical account managers will guide your project through every step
of the process and keep you informed of the latest progress.
Delivery Specifications: The typical delivery consists of lyophilized
sample in individual fully labeled vials. The shipment also contains COA, MS, HPLC and/or
other analytical data. Additional analytical data is also available upon request.
This service is for protein bioconjugation using various types of crosslinking
chemistries. See details on starting material provided by customer.
If you can't find what you want? Please contact us online with your detail project
Price: Price varies based on the project specifications. Our service includes materials
and labor for conjugation only! Price does not include the cost of biopolymer synthesis or purchase of biopolymer from a commercial vendor
and, if deemed necessary, biopolymer modification to introduce additional functional
groups, extra linkers, spacers. Please contact us for a quote.
Discount: 15 % discount pricing applies to additional conjugates ordered at the same time.
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.