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Single Domain Antibody (sdAb) Development Platform

Single domain antibodies (sdAb) can selectively bind to specific antigens and are widely used in the development of new drugs and the diagnosis of diseases. Our company has extensive expertise in therapeutic antibody development, particularly in single domain antibody development, our antibody development platform can provide efficient methods and personalized custom services to accelerate your development of rare disease therapy.

Introduction to Single Domain Antibody

Single domain antibody (sdAb), also known as domain antibody, nanobody (Nb), camelid antibody, VNAR, or VHH, is a type of antibody that naturally lacks light chains. Ordinary antibodies are composed of two heavy chains and two light chains, with a molecular weight of 150-160 kDa, while the molecular weight of single-domain antibodies is only 12-15 kDa. The first single domain antibodies were discovered in camelids. There is an antibody in the serum of camels that naturally lacks the light chain and heavy chain constant region 1 (CH1), called a heavy chain antibody (HcAb).

2-1-3-5 Single Domain Antibody (sdAb) Development Platform-1Fig.1 Comparison of antibody types. (Wilton, Emily E., et al., 2018)

Single domain antibodies are routinely prepared by immunizing camels with the antigen and screening the antibodies from the serum. However, when the antigen is highly toxic, a method combining nanobody gene library technology and phage display technology needs to be used to screen for the required antibodies.

Single Domain Antibody for Rare Diseases

Single domain antibodies not only have high tissue penetration and can cross the blood-brain barrier, but also have extremely high stability and can tolerate various adverse environments. Single domain antibodies have the advantages of good solubility, high production, and easy humanization, which make them have broad application prospects and value in the field of rare disease research. There are already cases of sdAb being used in the research of rare diseases:

Drug Types Caplacizumab Ciltacabtagene autoleucel Sonelokimab ALX-0141
Indications Thrombocytopenic purpura Multiple myeloma Psoriasis Postmenopausal osteoporosis

Our Services

With the world's leading antibody development platform and technology, our company can immunize various animals such as camels to support the development of sdAb. At the same time, we have rich preclinical research experience and can provide sdAb analysis services to accelerate your research on the therapeutics of rare diseases. Our services include but are not limited to:

Antigen Preparation

Provide high-purity antigen preparation to ensure its specificity and functionality, providing guarantee for subsequent research.


With rich experience, our company can quickly provide standard immunization protocol, and camel vaccination is a typical representative.

Library Construction and Screening

Utilize phage display technology for antibody library construction and screening, including immune, synthetic, and natural single domain antibody libraries.

Expression and Purification

To construct expression vectors for antibody expression, we have the ability to achieve high-throughput antibody expression and purify sdAb through protiein A or Ni affinity chromatography.

Why Choose Us?

  • Cutting-edge technology and equipment
  • Timely project reporting and after-sales service
  • Ph.D.-level scientists and skilled technicians
  • Fast and cost-efficient workflow
  • Expertise and experience in the industry
  • Cost-effective compared to other companies

Project Workflow

2-1-3-5 Single Domain Antibody (sdAb) Development Platform-3

With many years of experience and a proven track record of quality, innovation, and customer support, our company provides comprehensive services for leading and emerging biopharmaceutical companies and scientific research institutions to develop single domain antibodies (sdAb) for rare diseases. If you are interested in our services, please feel free to contact us for more details and quotation information of related services.


  • Wilton, Emily E., et al. "sdAb-DB: the single domain antibody database." ACS Synthetic Biology 7.11 (2018): 2480-2484.

All of our services and products are intended for preclinical research use only and cannot be used to diagnose, treat or manage patients.

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