In The News
Bio-Synthesis offers RNA-peptide conjugates in high quality and yields by using
various strategies, according to project specifications. Methods in preparing peptide-oligo conjugates are post-synthetic conjugation (or post-assembly
conjugation, fragment coupling strategy), total stepwise synthesis (or on-line solid phase
synthesis), native ligation and template-directed ligation. These RNA-peptide hybrids
have been become increasingly important in antisense therapy, due to the identification
of peptides as viable carriers for enhancing the cell delivery of antisense oligonucleotides.
RNA and peptide synthesis are produced in-house and conjugated by our expert scientists
in bioconjugation chemistry. Each peptide RNA hybrid is meticulously monitored
at each production cycle according to Bio-Synthesis’ stringent quality assurance
and quality control standards. The final product is identified by mass spectrum
and purity is analyzed by high throughput capillary gel electrophoresis. As always,
quality is guaranteed!
Bio-Synthesis is committed to Total Quality Management (TQM) to assure customers'
complete satisfaction. MS and HPLC analyses are performed following the completion
of RNA, peptide synthesis and cross linking DNA with peptide. QC
(quality control) and QA (quality assurance) procedures are also followed independently
to double guarantee the high quality of every delivered oligo-peptide conjugates.
Bio-Synthesis's Total Quality Management System (TQM) has been successfully upgraded
to fully comply with ISO 9001:2008 regulations.
Specification of RNA-Peptide Conjugates
The price depends on the method used in obtaining peptide-oligo conjugate. Please contact us for a quotation.
Single-stranded oligonucleotides are usually chemically modified by incorporation
of various nucleoside derivatives to protect against degradation by serum and cellular
nucleases. Double-stranded RNA is generally sufficiently stable in cell culture
to be used without modification, but are usually heavily modified with nucleoside analogs for in vivo use.
Methods in preparing peptide-RNA conjugates are post-synthetic conjugation (or post-assembly conjugation, fragment coupling strategy),total stepwise synthesis (or on-line solid phase synthesis), native ligation and template-directed ligation.
Example of using NHs ester-maleimide mediated conjugation chemistry where N-terminal
Cys incorporates peptide to react with a maleimide activated oligo. If the peptide has an internal Cys, we can use other strategies such as oxime formation through a hydroxyl-amine modified peptide reaction with an aldehyde modified oligo. Although the price for using other strategies for making peptide-oligo conjugate is the same,the price for obtaining other modified peptides, RNA oligo, or different cross-linking chemistries that include either stable or cleavable linkages may be higher.
Product is HPLC purified and usually over 85-95% pure.
All RNA and peptide synthesis and conjugation processes 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 by gel filtration. Then size-exclusion chromatography (SEC) or reverse phase (HPLC) may also be used to either remove excess reagent or isolate and characterized the cross-linked product. Once the product has been purified,it may be subject to many different types of studies including spectroscopic (MALDI-TOF,ESI, LC-MS Fluorescence) or electrophoresis studies.
QC (quality control) and QA (quality assurance) procedures are also followed independently
to offer you double guarantee for the highest quality possible.Final quantity is systematically validated by UV absorbance at 260 nm.Moreover, our dedicated technical account managers will guide you through every step of the process and constantly keep you informed of the latest project 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.
Contact our Technical Service Center at 800.227.0627 or contact us onlinewith your detail oligo-peptide project specifications, a project manager will be assigned to help you with design and develop an appropriate synthetic method for
your specific needs.
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.