Overview

We are a specialized biologics Contract Development and Manufacturing Organization (CDMO) with extensive expertise in Antibody Purification Services. Our dedicated downstream processing facility is equipped to purify monoclonal antibodies, polyclonal antibodies, recombinant antibody fragments (scFv, Fab, VHH), and other immunoglobulin-based molecules from diverse starting materials—including hybridoma cell culture, ascites fluid, mammalian expression system supernatants, and animal serum. We offer comprehensive, scalable solutions tailored to your specific needs, whether you require research-grade material for assay development or GMP-grade antibodies for clinical trials. Our team of experienced protein chemists and process engineers utilizes state-of-the-art chromatography systems and analytical instrumentation to deliver antibodies of exceptional purity, yield, and functionality, ensuring your project progresses smoothly from discovery through development.

☞What is Antibody Purification?

Antibody purification is a critical series of biochemical separation processes designed to isolate target antibody molecules from a complex mixture of contaminants. The starting material (the "feedstock") contains the desired antibodies alongside host cell proteins (HCPs), nucleic acids, media components, viruses, endotoxins, aggregates, and other process-related impurities. Effective purification is essential for several reasons:

• Functional Reliability: Contaminants can interfere with antibody-antigen binding, block conjugation sites, or cause non-specific interactions, leading to unreliable assay results or therapeutic side effects.

• Stability & Storage: High-purity antibodies are more stable, less prone to aggregation, and have longer shelf lives.

• Safety (for in vivo use): Therapeutic and diagnostic in vivo applications require the removal of immunogenic or toxic impurities like endotoxins, viruses, and host cell DNA.

• Regulatory Compliance: Manufacturing antibodies for clinical use must adhere to strict regulatory guidelines (e.g., FDA, EMA) regarding purity, potency, and safety, which are defined by specific purity thresholds (often >95-99%).

Our service transforms your crude antibody sample into a characterized, buffer-exchanged, ready-to-use product suitable for your downstream applications.

☞Antibody Purification Technology Principles & Process

Our purification strategies follow a proven, multi-step orthogonal approach, where different separation techniques are combined to remove distinct classes of impurities effectively.

 Core Purification Workflow: 

Step 1: Capture & Primary Purification

● Technology: Affinity Chromatography is the industry-standard first step for most IgG antibodies.

● Principle: Utilizes the specific, reversible interaction between the antibody's Fc region and a ligand immobilized on a chromatography resin.

1. Protein A Chromatography: Binds human, mouse, and rabbit IgG with very high affinity and specificity at neutral pH. Elution is achieved under mild acidic conditions (pH ~3.0). This step achieves >95% purity in a single run and significantly reduces volume.

2. Protein G Chromatography: Broader binding specificity, ideal for rat, goat, sheep, and cow IgGs, and certain mouse IgG subclasses that bind poorly to Protein A.

3. Antigen-Specific Affinity: For unique applications, we can immobilize the target antigen to create a custom resin that captures only antigen-specific antibodies from polyclonal sera.

Step 2: Polishing & Impurity Removal

Following capture, the antibody undergoes further polishing steps to remove remaining impurities:

● Cation Exchange Chromatography (CEX): Separates molecules based on net surface charge at a given pH. Effective for removing residual HCPs, DNA, leached Protein A/G, and antibody fragments. Often run in bind-and-elute mode.

● Anion Exchange Chromatography (AEX): Typically operated in flow-through mode, where the negatively charged impurities (DNA, viruses, endotoxins) bind to the positively charged resin, while the antibody flows through. This is a highly effective "clean-up" step.

Step 3: Aggregate Removal & Final Formulation

● Size Exclusion Chromatography (SEC or Gelf Filtration): Separates molecules based on size. This is the final polishing step to remove high-molecular-weight (HMW) aggregates and low-molecular-weight (LMW) fragments, yielding a monomeric antibody preparation. It also serves to exchange the antibody into its final formulation buffer (e.g., PBS, histidine buffer).

● Viral Clearance (for GMP processes): Dedicated steps like virus filtration (nanofiltration) or low-pH incubation are integrated to ensure product safety.

Step 4: Concentration & Buffer Exchange

● Using tangential flow filtration (TFF) or centrifugal concentrators, the antibody is concentrated to the target concentration and diafiltered into the final storage or formulation buffer.

Step 5: Sterile Filtration

● The final product is passed through a 0.22 µm filter to ensure sterility.

☞Classification and Comparison of Antibody Purification Methods

Choosing the right purification strategy depends on the antibody source, isotype, scale, required purity, and intended use. The table below compares the core techniques we employ:

Our Recommendation Paths:

• Standard Monoclonal IgG (from cell culture): Protein A Capture → CEX Polishing (Bind/Elute) → AEX Polishing (Flow-Through) → SEC (Formulation).

• Polyclonal IgG from Serum: Clarification/Caprylic Acid Precipitation → Protein A/G Capture → SEC (or IEX) Polishing.

• Antibody Fragments (Fab/scFv): Affinity tag (His-tag, FLAG) Capture → IEX Polishing → SEC.

☞Our Service Workflow

Our client-centric workflow is designed for seamless collaboration, transparency, and timely delivery.

Step 1: Project Consultation & Feasibility Assessment

We discuss your antibody source, format, quantity, required purity specifications, and intended use. Based on this, we recommend a purification strategy and provide a detailed project proposal and quote.

Step 2: Sample Submission & Initial Analysis

You ship your starting material. We perform an initial analytical assessment (titer, SDS-PAGE, aggregate content) to confirm the process design.

Step 3: Process Execution & In-Process Monitoring

Our purification team executes the agreed-upon protocol. We monitor key parameters (UV absorbance, pH, conductivity) and collect samples at each step for analysis.

Step 4: Analytical Characterization & QC

The final purified antibody undergoes comprehensive QC, which may include:

• Purity: SDS-PAGE (reducing/non-reducing), SEC-HPLC for aggregate quantification.

• Concentration: A280 measurement with calculated extinction coefficient.

• Identity: Mass Spectrometry (LC-MS) or Isoelectric Focusing (IEF).

• Functionality: Antigen-binding ELISA or SPR/BLI.

• Safety: Endotoxin (LAL) testing, sterility testing, and residual host cell protein (HCP) or DNA analysis as required.

Step 5: Final Reporting & Product Delivery

We compile a comprehensive Purification Report and Certificate of Analysis. The purified antibody is sterile-filtered, aliquoted as requested, and shipped under appropriate conditions (wet ice, dry ice, or lyophilized).

 Our Service Process Flowchart: 

☞Why Choose Our Purification Service?

• End-to-End Expertise & Scalability: We handle projects from milligram-scale research purifications to gram/kilogram-scale GMP manufacturing under one roof, providing a seamless path as your project advances.

• Advanced Technology Platform: Our facility is equipped with AKTA™ chromatography systems, TFF systems, and state-of-the-art analytical tools (U/HPLC, LC-MS, SPR) to ensure precise process control and rigorous quality assessment.

• Focus on Quality & Regulatory Insight: Whether your need is research-grade or GMP-compliant, we operate under a robust Quality Management System. Our scientists have deep regulatory knowledge to guide processes for preclinical and clinical applications.

• Customized, Flexible Solutions: We don't offer a one-size-fits-all approach. We tailor the purification strategy to your specific antibody's properties and your final application's requirements.

• Transparent Communication & Data Delivery: You receive detailed documentation at every stage, including chromatograms, gel images, and analytical data. We believe in partnership and keep you fully informed throughout the process.

• Maximized Yield & Activity: Our optimized protocols are designed not only to achieve high purity but also to maximize recovery of functional, active antibody, preserving your valuable product.

Partner with us to transform your crude antibody material into a high-purity, fully characterized, and application-ready product. Contact our team to discuss your purification needs and receive a detailed project proposal.