"ECOLOGIENA" is a result of our biotechnology to detect pollutants such as surface active agents, and bisphenol A, which is suspected as one of the endocrine disrupting chemicals.
The mechanism called Enzyme-Linked Immunosorbent Assay (ELISA) enables to detect chemicals at a very low level without complicated sample preparation.


Total Estrogen (E1/E2/E3) ELISA Kit
96well Microplate Kitt
17β-Estradiol (E2) ELISA Kit 96well Microplate Kit
Estrone (E1) ELISA Kit 96well Microplate Kit
Ethynylestradiol (EE2) ELISA Kit 96well Microplate Kit
Supersensitive Bisphenol A(BPA) ELISA 96well Microplate Kit
Alkylphenol(AP) ELISA Kit 96well Microplate Kit
Anionic Surfactant LAS ELISA Kit 96well Microplate Kit
Nonionic Surfactant APE ELISA Kit 96well Microplate Ki

What is ELISA?


ELISA is an analytical technique that uses a monoclonal antibody and an enzyme-labeled antigen. The antibody obtained through our elaborate screening, maintains an optimum antigen binding site (epitope), allowing highly specific detection of target substance(s).

ECOLOGIENA━ ELISA from TOKIWA Chemical Industries, accomplishes a wide dynamic range. With the aid of simple pretreatment (filtration and solid phase extraction), more sensitive determination is achievable.

The test protocol does not require harmful organic solvent, providing safer operating environment.

How does ELISA Work?

1. Competitive Reaction
The inner surface of a well is coated with the protein called monoclonal antibody, which binds exclusively with an analyte (pollutant). The analyte derived from samples and an antigen-enzyme conjugate, which is an analyte labeled with a coloring enzyme, are premixed and subject to immobilized antibody for a competitive assay, vying for a limited number of antibody binding sites. When the analyte concentration is higher relative to the enzyme conjugate, the analyte will predominantly bind antibody and vice versa.

2.Chromogenic Reaction
Unbound analytes and excess antigen-enzyme conjugates are washed out. Then the chromogenic substrate is added to develop color in conjunction with conjugated enzyme. The amount of antigen-enzyme conjugate remaining with antibody will determine color intensity. The higher concentration of target substance in sample, for example, leads to less antigen-conjugate on antibody, generating lighter color, i.e. lower absorbance.

3. Quantification
The standard curve, a dose-response curve from known concentrations of analyte, is determined from the absorbance from a certain wavelength (e.g. 450nm for horseradish peroxidase and tetramethyl benzidine). The analyte concentration is accurately calculated from the response intensity of absorbance.

How does ELISA Work?:figure

Monoclonal Antibody and Antigen-enzyme Conjugate

Hapten* and carrier** are bound together to form an immunogen.

*Hapten: Hapten is a small molecule which is not antigenic in itself but when attached to a large molecule can stimulate the formation of antibodies.

**Carrier: Carrier is an immunogenic substance that, when coupled to a hapten, renders the hapten immunogenic.

Immunogen is mixed with adjuvant, a substance improving the immune response to an antigen, and is injected to mice at two weeks・interval. The spleens are extracted and the lymphocytes or spleen cells are hybridized with myeloma or 咄umor・cell line to form hybridomas, each of which continuously secretes a single antibody molecule.

3. Monoclonal Antibody
The hybridomas, once confirmed for their viability, are screened out with ELISA over their antigen bonding ability to obtain the most sensitive cell. Then, the hybridoma from the supernatant is purified and prepared for a highly specific monoclonal antibody.


4. Antigen-enzyme Conjugate
Hapten is bound to an enzyme to prepare antigen-enzyme conjugate.