Enhanced Diagnostic Tools
Bio-Synthesis offers its customers a team of specialists and experts in the development
of immunoassays by conjugating peptides, proteins, antibodies, and oligonucleotides
with fluorescent or dyed latex particles that are useful in multiplexed suspension
bead array detection systems such as Luminex ® technology. Whether it be multiplex
several existing individual assays or developing new tests for new markets, our
team will accompany you in your project by bringing skills and wanted resources.
Fluorescent beads conjugation, feasibility study, complete assay development, reagent
manufacturing, sample testing are among the services proposed on our multiplexed
assay platform. For details contact us regarding luminex assay service.
Luminex Bead Conjugation Services:
The Luminex xMAP technology is a microsphere-based multiplexing system for detection
and quantitation of multiple analytes such as RNA or protein targets simultaneously
in a single sample. A specific antibody to the target protein is covalently coupled
to internal fluorescently dyed beads. The beads with bound target proteins are separated
by laser excitation and quantitated. Beads coupled with different antibodies, each
with a distinct fluorescence signature, are mixed, thus enabling simultaneous assay
of multiple protein targets in a single well of a 96-well plate. This is a sensitive
quantitative assay that enables detection of proteins in cell extracts and extra-cellular
fluids at very low concentrations (1 pg/ml), and thus is excellent for analysis
of signaling pathways and regulatory proteins. We currently support a Luminex 200
(Bio-Plex) instrument and have optimized and provide Luminex assays for cytokines,
growth factors, apoptosis, cancer, metabolic markers, and Akt and MAP kinase signaling
pathways. As commercial vendors expand the range of Luminex beads, we will validate
assays for new bead kits as they become available. For details, contact us for Luminex
Bio-Synthesis ensures high quality conjugated are produced by using unique expertise
in bioconjugation chemistries.
Contact our Technical Service Center at 800.220.0627 or contact
us online with your detail project specification and a project manager will
be assigned to help you design and develop an appropriate synthetic method for your
1.Antibody/protein supplied by customers should be sufficiently pure. Please provide
1 mgs of purified antibody/protein or oligos with the necessary data for purity
assessment. Commerically available biopolymers can be supplied by customers or synthesize
or ordered through Bio-Synthesis. If you want more protein attached to the Luminex®
bead set please let us know.
2.The antibody/protein must be supplied in a protein-free buffer solution. There
must not be bovine serum albumin (BSA) or gelatin, etc. in the buffer solution or
we will not be able to effectively link your protein to the Luminex® bead set.
3.We recommend that the antibody/protein be supplied in phosphate-buffered saline
(PBS) buffer, the buffer formulation used during the linking process.
4.Please avoid adding preservatives to the protein preparation, such as sodium azide
or merthiolate. These agents can inhibit the protein conjugation reaction.
5.Please avoid adding high levels of viscous agents to your protein preparation
such as either glycerol, ionic detergents or non-ionic detergents as they can inhibit
the bead conjugation reaction.
(~4,000 – 5,000 Assay Points; ~4 µg/106 beads; ~4 pg/bead) single-conjugation
Price varies based on project specifications. Price does
not include cost of small molecule or biopolymer which we require to be supplied
by customer or ordered through Bio-Synthesis from a commercial vendor. Some of the
small molecules are commercially available in an activated form. For non-active
molecules, Bio-Synthesis can assist with the design and, if deemed necessary, biopolymer
modification to introduce additional functional groups and extra linkers.
Please contact us for a quote.
Coupling of preactivated small molecule and biomolecule
with bead containing chemical reactive groups such as carboxyl for binding protein
or other macromolecules. Proteins are coupled to the beads by conjugating the free
amines of lysine sidechains and the N-terminal amines of proteins to the carboxyl
groups on the beads. Bead coupling is a two-step procedure. The first step is to
activate the microspheres with EDC/Sulfo-NHS. The excess is removed and then protein
is added. After the protein is conjugated to the beads, the remaining sites are
blocked with detergent or BSA.
1.Unless requested otherwise, the conjugated beads will be formulated in phosphate-buffered
saline (PBS) containing 1% BSA and 0.05% sodium azide and shipped back at 4ºC.
2.The labeled Luminex® beads will shipped within 2 weeks after receipt of the
Store coupled microspheres refrigerated at 2-8°C in the dark.
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.