Design and Synthesis of Haptens for Ochratoxin B (OTB)

Ochratoxins are known as common contaminants in human food and animal feed, prevalently detected in cereals, coffee, beer, and wine. Ochratoxin B (OTB) is a secondary metabolite of mycotoxins and belongs to a member of the ochratoxin family. Proteins are the strongest immunogens, while haptens can’t elicit an immune response in the organisms. There’re no sufficient reports regarding OTB hapten preparation. In order to induce the immunogenicity of haptens, they’re chemically conjugated to carrier proteins, acting as a part of that carries. As a well-recognized antibody supplier in the world, Creative Biolabs is committed to the latest advancement and development of anti-hapten antibody research, as well as offers effective design and synthetic strategies to generate OTB haptens for global clients.

Introduction to OTB

OTB is a phenylalanine derivative derived from the condensation of the amino group of L-phenylalanine with the carboxy group of (3R)-8-hydroxy-3-methyl-1-oxo-3,4-dihydro-1H-2-benzopyran-7-carboxylic acid. This toxin has differences with the more abundant ochratoxin A (OTA) in the absence of dihydroisocoumarin chlorine atom. Because of its rapid metabolism and excretion, OTB shows cytotoxic effects on kidney and liver cells in vitro but has only minor effects in vivo. It can inhibit cell proliferation of human liver cells at concentrations as low as 0.1 ng/mL, whereas lacking the genotoxic activity of OTA, even at a higher concentration. OTB has normally been considered less toxic and its effects are mainly dependent on the model chosen. This molecule plays a role as an Aspergillus metabolite, a Penicillium metabolite, together with a calcium channel blocker.

Chemical structure of OTB Fig.1 Chemical structure of OTB.

Rational Hapten Design Services at Creative Biolabs

OTB is the non-chlorinated analog of the naturally OTA, and there is evidence suggested that OTB has a distinct mode of action than OTA. In recent studies, a monoclonal antibody specifically binding to OTB has been employed for the development of an indirect competitive OTB-ELISA. Owing to very low cross-reactivity to OTA (2.7%) and no structural relevance (0%), the OTB-ELISA is suitable to identify OTB with excellent precision in various matrices, for example, beer, coffee, and wine.

Design and Synthesis of Haptens for Ochratoxin B (OTB)

Haptens are not immunogenic because even they may pose a threat to the organism, they could be detoxified by chemical modification with kidney enzymes. And there’s no necessity to initiate the energy-consuming humoral immune activities. Remarkably, researchers demand an immune response against hapten molecules, since specific antibodies are needed to be used in immunodiagnostic systems. To be able to allow such immunogenicity in the non-immunogenic antigen, Creative Biolabs has developed multiple strategies for OTB hapten design and synthesis. Through linking OTB derivatives to macromolecule carrier proteins (such as BSA, RSA, HAS, KLH…), artificial antigens are immunogenic so that to cause antibody responses. Our coupling methods of hapten derivative with a carrier can be performed by chemical coupling methods and other effective methods.


  • Fast, sensitive, and selective design strategies and synthetic tools to produce high-quality OTB happens
  • Several protein carriers with stable properties confer the immunogenicity of small molecular haptens
  • High-level technical platforms and dedicated devices help clients to advance their challenging projects

Immunoassays, especially antigen-antibody reactions, are potent approaches for available, sensitive, selective, high-throughput detection of numerous samples. As a famous custom antibody provider, Creative Biolabs has rich knowledge in generating antibodies against small molecular compounds. We’d like to offer one-stop services from experiment design, hapten preparation, to antibody production to meet clients’ special needs on OTB. If you’re interested in our services, please don’t hesitate to contact us or directly send us an inquiry.

All listed services and products are for Research Use Only. Do Not use in any diagnostic or therapeutic applications.
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