Aptamers

Aptamers are extremely useful in a range of biotechnological and therapeutic applications, and offer many advantages over antibodies:

The unique secondary and tertiary structures of aptamers provide the specificity to detect even small structural changes in the target molecule, including the presence or absence of methyl or hydroxyl groups or differences in enantiomeric configurations.

Aptamers that bind specific targets are identified through a process known as Systematic Evolution of Ligands by Exponential enrichment (SELEX) in which binding molecules are selected from a large and diverse library of nucleic acids (either DNAs or RNAs). In this process, the nucleic acid library is incubated with the target molecule. Non-binding nucleic acids are then washed away, leaving behind only the molecules that have a capacity to bind to the target molecule.

The nucleic acids that are not washed away are then used to create a new library of nucleic acids that is enriched for the subset that binds the desired target. Repeating this selection-cycle on each subsequent library with increasing stringency of binding (e.g. lower concentration of target), ensures that nucleic acids that bind to the target with both high specificity and high affinity are enriched.

Aptoprecipitation (AP)/Co-aptoprecipitation (Co-AP) kits are aptamer based protein precipitation kits for easy and quick protein precipitation, offering numerous advantages over other competing methods.

• Complete kits: Aptamer provided as covalently conjugated to magnetic beads, so no troublesome conjugation step is necessary
• Mild elution condition
• Specificity: Aptamer recognizes the native form of target proteins, not the denatured form, unlike antibodies
• Reusable aptamer beads
• Storage and longer shelf life: stable even at high temperatures and for at least 1 year when stored at room temperature

AMSBIO offers dye-conjugated aptamers specifically designed to monitor protein expression by flow cytometry with high specificity. Flow cytometry facilitates quantitative, multi-parameter analysis of cell populations based on the expression of cell surface and/or intracellular molecules.

We supply a wide range of dye-conjugated monoclonal aptamers, which are compatible with all flow cytometers.

• Range of dyes: Fluorescein isothiocyanate (FITC), cyanine (Cy3, Cy5) and others
• Dye conjugations available at 5’ or 3’ end
• High specificity: minimizes background caused by nonspecific binding

• No secondary antibody or aptamer needed
• No batch to batch variation
• Storage stability- fluorescent dye-conjugated aptamers are stable for at least several months at room temperature

AMSBIO offers the user-friendly AptoPrep™ Cell Isolation Kit for your cell isolation needs. Utilizing the specificity of aptamers to target cells, AptoPrep™ allows for the convenient isolation/elution of a particular cell from complex cell samples.

• Fast, easy-to-use kit: Positive isolation in as little as 30 min. Released cells from bead are obtained in as little as 1 hour
• Complete kit- biotinylated aptamer, streptavidin magnetic bead, and buffers are supplied for your convenience, increasing consistency and reliability
• High specificity, yield, purity and viability
• Mild and unique cell releasing technology allows you to isolate beads and aptamer-free cells. The isolated bead-free cells are ready for flow cytometry analysis and downstream molecular studies
• No columns required- saves time and money, and your cells are not exposed to the stress of being passed through a dense column
• Convenience in handling and longer shelf life

As well as biotinylated aptamer, we supply kits with FITC dye conjugated biotin aptamer, allowing you to perform the cell isolation and flow cytometry analysis simultaneously. Our bi-labeled aptamers have FITC at the 5’-end to monitor protein expression by flow cytometry and biotin at the 3’-end to separate target cells.