Nucleic acid aptamers are short, single-stranded oligonucleotides (ssDNA or ssRNA) capable of binding with high affinity and specificity to diverse targets, ranging from small molecules and proteins to entire cells. Due to their versatility and stability, aptamers have become invaluable tools in both basic research and clinical applications. The standard method for aptamer identification is Systematic Evolution of Ligands by Exponential Enrichment (SELEX), an iterative process involving repeated cycles of incubation, separation, elution, amplification, and single-strand purification, followed by sequencing. At KMDbioscience, we have established a proprietary and highly optimized platform for efficient and reliable aptamer screening. Our services cover aptamer development against both purified protein targets and small chemical molecules. Through our refined selection process, we consistently generate DNA aptamers with dissociation constants (Kd) in the range of 0.1–10 nM. Typically, multiple unique aptamer sequences can be identified through successive selection rounds. Depending on client needs, we can provide the full panel of candidate aptamers obtained from the screening campaign. Choose KMDbioscience as your partner to accelerate and enhance your aptamer-based projects. Let us help you advance your research and development goals with precision and expertise. Aptamer Screening Service | Aptamer Development
Custom-Tailored Aptamers with Exceptional Affinity and Specificity for Your Target Molecules Aptamers are powerful tools in biotechnology and therapeutic development, offering molecular recognition properties that rival traditional antibodies. In addition to their high targeting precision, custom aptamers provide distinct advantages: they are developed entirely in vitro, can be rapidly produced through chemical synthesis, exhibit excellent stability in storage, and show minimal immunogenicity in therapeutic contexts. KMDbioscience delivers a dedicated service to generate high-quality aptamers against your chosen targets, achieving reliable results even with complex or challenging molecules. Our aptamers are available with a range of fluorescent labeling options to support convenient detection and visualization in your applications. Our custom aptamer development utilizes a proprietary SELEX technology, enabling the rapid generation of aptamers with high binding affinity for your target molecules. Our custom aptamer services include: Aptamer Discovery Advanced SELEX using modified nucleotides Traditional SELEX using natural nucleotides Competitive and/or negative selection strategies Maturation SELEX (second-round selection using a pre-screened focused library) Aptamer Modification End-Group Modification (5’ and/or 3’): Amine, Thiol, Biotin, various fluorescent dyes, PC Biotin, PC Amine, idT, Cholesterol, etc., with or without linkers (dT, dA, HEG, PEG, etc.) Internal Modification: 2’-OMe, internal amine, internal biotin, etc. Conjugation: Pegylation (linear, branched, lysine-branched),…
Root Cause of Low Immunogenicity: Chemical Nature Aptamers: These are single-stranded DNA or RNA molecules. Composed of nucleic acids, their chemical structure closely resembles that of naturally occurring nucleic acids in the human body (such as tRNA and microRNA). The human immune system has evolved to generally not mount strong immune responses against self-nucleic acids. Protein/Antibody Drugs: These are exogenous proteins. Even after humanization, their amino acid sequences and spatial structures may still be recognized as "non-self" by the immune system, potentially leading to the production of anti-drug antibodies (ADAs). Types and Impact of Immune Responses Aptamers: The likelihood of triggering an immune response is extremely low. This means: Fewer side effects: Reduced risks of allergic reactions, cytokine storms, etc. Repeatable dosing: Less likely to lose efficacy due to the production of neutralizing antibodies. Longer half-life: Not rapidly cleared by the immune system. Antibody-Based Drugs: Carry the risk of inducing ADAs, which may lead to: Drug inefficacy: ADAs may neutralize drug activity. Altered pharmacokinetics: Accelerated drug clearance. Severe adverse reactions: Such as infusion-related reactions. Optimization Strategies in Aptamer Development Services Specialized Aptamer Development Services employ the following design strategies to further minimize or circumvent any potential immunogenic risks: Chemical Modifications:…
Features Highlighted by an Aptamer Development Service When promoting their services, a development company will emphasize these practical and commercial advantages: 1. ** In Vitro Process Advantages Complete In Vitro Control: The entire selection process (SELEX) is performed in a controlled, cell-free environment. This allows for precise manipulation of selection conditions (pH, temperature, ionic strength, presence of competitors) to fine-tune aptamer properties. Speed and Cost-Effectiveness (in certain contexts): The development cycle can be as short as 2-3 months, significantly faster than the 4-6 months for monoclonal antibody development, especially for challenging targets. 2. Tailorability for Specific Applications A key service offering is to customize the SELEX process based on the client's end-use: Diagnostic Aptamers: Selected for binding in buffer conditions similar to the diagnostic matrix (e.g., serum, urine). Therapeutic Aptamers: Selected under physiological conditions (pH 7.4, 37°C, relevant ion concentrations) and can include counter-selection against serum proteins. Cell-Specific Aptamers: Use whole living cells as targets to discover markers for specific cell states (e.g., cancer stem cells). 3. Rational Design and Engineering Services often include post-SELEX optimization. Truncation: Identifying the minimal, high-affinity binding core sequence. Stabilization: Incorporating modified nucleotides to resist nucleases in biological fluids. Multimerization: Designing dimeric or multimeric aptamers for increased avidity and signal. Generation of Aptasensors: Engineering aptamers into switching constructs (e.g., structure-switching aptamers) for…
Key Strengths of Your Description: Scale of Diversity: Highlighting the library size (up to 10^15 unique sequences) is crucial. This immense diversity is the starting pool from which "winners" are found. Structure of Library: You correctly note the design: a central random region (for binding diversity) flanked by fixed primer regions (for PCR amplification). Iterative Cycles: The heart of SELEX is the repeated cycle of Binding -> Partitioning (Washing) -> Elution -> Amplification. Each round increases the proportion of high-affinity binders. Importance of Conditions: Emphasizing the control of buffer, pH, temperature, etc., is key. These counter-selection or negative selection steps are vital to ensure the resulting aptamers bind specifically to the target (e.g., a protein's active site) and not to the container or other irrelevant components. A Slightly Expanded Framework for Clarity: To complement your text, here’s a visual summary of the classic SELEX cycle: The Classic SELEX Cycle (Visualizing Your Description): text [Step 1: INCUBATION] Combinatorial Library (10^15 sequences) + Target Molecule | [Step 2: PARTITIONING] |-> Bound Sequences (to target) --[ELUTION]--> Recovered Aptamer Candidates |-> Unbound Sequences (washed away) | [Step 3: AMPLIFICATION] Recovered Candidates --[PCR (DNA) / RT-PCR (RNA)]--> Enriched Library | [Step 4: REPETITION] New Enriched Library ---(Return to Step 1 for next round, 8-15 rounds typical)--->…
Akmdbioscience ptamer Screening Advantages Cost-Effective Production Aptamers screened by us can be produced at less than 10% of the cost of antibody production, delivering significant savings without compromising quality. High Affinity & Specificity Our service ensures the selection of aptamers with strong binding affinity and specificity, suitable for demanding research and diagnostic applications. Versatile Screening Applications We provide a powerful platform for screening medicinal species, identifying active structures, and enriching active ingredients — accelerating discovery in therapeutics and diagnostics. Expert Team & Proven Experience Benefit from our excellent research staff with many years of specialized experience in aptamer development, supported by CD Bioparticles' rich expertise in nucleic acid aptamer screening. Reliable & Transparent Results We deliver objective, realistic experimental outcomes with a guaranteed project timeline to ensure your success. Comprehensive Service Offering CD Bioparticles offers end-to-end screening and synthesis services for different target-based nucleic acid aptamers. We commit to delivering at least one aptamer sequence with KD < 300 nM per project. Interested in learning more? Contact us today for detailed information and to discuss how our aptamer screening services can support your goals.
Applicable Targets: Proteins, small molecules, cells, bacteria, etc. Protein Delivery Requirements: Please provide information on protein size, volume, concentration, protein buffer formulation, protein gel image, whether the protein contains tags, and corresponding tag details. Small Molecule Delivery Requirements: Please provide information on sample mass (in grams), concentration, volume, and storage conditions. For Cell and Bacterial Targets: Please inquire for specific delivery requirements and sample volume before submission. Deliverables: NGS sequencing results, a comprehensive experimental report (including experimental procedures, enrichment rate data during the screening process, and relevant photos, etc.).
Aptamer Screening Service Workflow This is a detailed explanation of the Aptamer Screening Service Workflow. Aptamer screening, also known as SELEX, is an iterative in vitro selection process used to isolate nucleic acid molecules with high affinity and specificity for a given target from a random oligonucleotide library. A complete aptamer screening service typically follows this standardized workflow, which can be divided into several core stages: Stage 1: Project Design and Initiation Requirement Communication and Target Confirmation Target Properties: Define target type (protein, small molecule, cell, virus, etc.), purity, concentration, and availability. Screening Objective: Determine the intended application of the aptamers (diagnostics, therapeutics, detection, etc.), which dictates the stringency of the screening (e.g., the need for counter-selection/negative selection). Chemical Modification: Decide whether to use modified nucleotides (e.g., 2'-F, 2'-O-Me) to enhance aptamer stability and nuclease resistance. Library Design: Determine the length of the random region (typically 30-50 nt) and the flanking primer sequences. Protocol Development and Contract Agreement The service provider develops a detailed Experimental Protocol based on requirements, including the number of selection rounds, positive/negative selection strategy, separation methods, expected deliverables, etc. Both parties finalize the protocol, timeline, cost, and sign a contract. Stage 2: SELEX Selection Cycle (Core Process) This is a repetitive…
KMD Bioscience: Aptamer Screening & Development Services We provide comprehensive, custom aptamer development services using advanced screening technologies (like SELEX). Our services are designed to isolate high-affinity, specific aptamers for a wide range of targets. 1. By Aptamer Type We screen and develop aptamers composed of different molecules: RNA Aptamer Screening: Develop aptamers from RNA libraries. DNA Aptamer Screening: Develop aptamers from DNA libraries. Peptide Aptamer Screening: Develop short, structured peptide binders. 2. By Target Type & Application Our expertise covers diverse molecular and cellular targets: Cell-Specific Aptamer Screening (Cell-SELEX): Isolate aptamers that bind specifically to a particular cell type (e.g., cancer cells, stem cells), often targeting unknown surface markers. Protein/Antibody Binding: Develop aptamers for specific protein or antibody targets for diagnostics or therapeutics. Peptide Binding: Generate aptamers targeting specific peptide sequences. RNA Binding: Select aptamers that bind to structured or unstructured RNA targets. Small Molecule Binding: Create aptamers for haptens, drugs, toxins, or other small molecules. DNA-Binding Protein Binding: Develop aptamers that interact with proteins designed to bind DNA. Key Service Advantages: Custom Development: Tailored assays to meet specific research or commercial goals. High-Affinity Selection: Advanced processes to isolate strong and specific binders. Broad Expertise: Capability to work with targets from small molecules to whole cells. Note: For the most accurate and…
Nucleic acid aptamers, often termed "chemical antibodies," exhibit high affinity and specificity for target molecules, mirroring the recognition capabilities of conventional antibodies. They present a transformative potential to supplant antibodies across diverse fields including biosensing, in vitro diagnostics, therapeutic development, and biomedical research. Once selected, aptamers offer significant advantages: they can be chemically synthesized with exceptional batch-to-batch consistency at a fraction of the cost (typically less than 10%) of antibody production. Furthermore, they demonstrate superior stability, ease of modification, and reduced immunogenicity. [caption id="attachment_707" align="alignnone" width="2560"] www.DesireFX.me[/caption] At KMD Bioscience, our core expertise lies in the advanced screening and development of these highly structured DNA or RNA molecules. Our process is built upon the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) methodology. The fundamental SELEX cycle involves: Incubation of a vast combinatorial nucleic acid library with the target. Partitioning to isolate target-bound sequences from unbound ones. Amplification of the recovered sequences to generate an enriched library for the next selection round. We leverage and continuously innovate upon this foundational technology with proprietary strategies and state-of-the-art platforms—such as Capture-SELEX, Cell-SELEX, and Next-Generation Sequencing (NGS)-accelerated approaches—to deliver high-performance aptamers with efficiency and precision for our clients' specific applications.
