Enhanced Diagnostic Tools
Bio-Synthesis provides a one-stop solution for all of your peptide-macromolecule bioconjugation needs. Our custom peptide synthesis, modification, and conjugation services involve chemical modification of peptide at highly specific sites. This allows for the elegant
attachment of labels such as fluorescent, chemilluminescent, or chromogenic enzyme
substrates. Applications include surface immobilized probes to facilitate diagnostic detection or as drug delivery agents when the peptide is conjugated with any molecular
group that adds useful properties—including radionucleotides, drugs, toxins, enzymes, metal chelates, fluorophores, haptens, and others.
Bio-Synthesis gives you the best quality in peptide bioconjugation chemistry in
the industry by implementing our state-of-the art gene synthesis platform and expertise
in providing high quality nucleic acid bioconjugation reagents. Peptide synthesis,
modifications, and conjugates produced at Bio-Synthesis have substantial purity.
Each peptide-biopolymer conjugate is meticulously monitored during synthesis and
controlled according to our quality assurance and quality control standards. The
final product is identified by mass spectrum, amino acid analysis, and the purity
is analyzed by HPLC or appropriate analytical methods. QA (quality assurance) procedures
are also followed independently to double guarantee the high quality of every delivered
peptide. Bio-Synthesis is complient with TQM (Total Quality Management) system.
Bio-Synthesis is a leader in custom peptide synthesis and bioconjugation services with a high success rate well above the industry standard. 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
Over 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 800.227.0627, or contact us online with your detailed project descriptions.
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-lengthcross-linking, homobifunctional, heterobiofunctional, or multifunctional cross-linking
chemistries, dendrimer and dendrons, and cleavable reagent systems.
Some commonly used cross-linking reagents include:
Bioconjugate chemistry may occur through the C- and N-terminals of each polypeptide chain, the carboxylate groups of aspartic and glutamic acids, the ϵ-amine of lysine,
the guanidino group of arginine, the sulfhydryl group of cysteine, the phenolate
ring of tyrosine, the indol ring of tryptophan, the thioether of methionine, and
the imidazole ring of histidine.
After standard desalting, or purification,
a small percent of heterogeneous products containing single or multi-site conjugate
per molecule may exist.
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 may suffice to remove unreacted reagent from the reaction
solution. Depending on the project scope, size-exclusion chromatography (SEC) or
HPLC may also be used to either remove excess reagent or to isolate and characterize the cross-linked product. 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.
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.
If you can't find what you want? Please contact us online with your detail project descriptions.
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 from a commercial vendors other than Bio-Synthesis and, if deemed necessary, biopolymer modification to introduce additional functional groups, extra linkers, spacers. Please contact us for a quote.
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. Provide us with your project details will enable to us to recommend the best reagents to use for your 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 aremore 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 and length of the spacer arm 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.
Within 3-5 days upon receiving your project scope, we will provide you an appropriate quotation. An order can be placed with PO (Purchase Order) or major credit cards ( ). Your credit card will be billed under Bio-Synthesis, Inc.