Development of Chemiluminescent ELISA for Detection of Diisobutyl Phthalate in Water, Lettuce and Aquatic Organisms

Abstract

The use of plasticizers to improve the quality of plastics widely used for household purposes inevitably leads to an increase in their pollution of food and environmental objects. Diisobutyl phthalate (DiBP) is one of the ortho-substituted phthalic acid esters that negatively affect human health and ecosystems. This work is directed to the development of a chemiluminescent enzyme immunoassay (CL-ELISA) for the determination of diisobutyl phthalate in water and food. Luminol, which is oxidized with hydrogen peroxide in the presence of p-iodophenol as an enhancer, was chosen as the substrate for horseradish peroxidase used as a label in the analysis. For this development, rabbit anti-DiBP polyclonal antibodies were generated and tested with the synthesized hapten–protein conjugate. The developed chemiluminescent ELISA has a detection limit of 1.8 ng/mL; the operating range was 5.0–170.8 ng/mL at a content of 10% methanol in the assay medium. The assay was successfully applied to detect diisobutyl phthalate in lettuce leaves, seafood, and water. When using extraction with methanol and hexane, the recovery of DiBP in samples varies in the range of 76.9–134.2%; for assays in natural waters, the recovery rates are from 79.5 to 113.4%.

Determination of Nonylphenol in a Highly Sensitive Chemiluminescent Immunoenzyme Assay of Natural Waters

“…No further measurements were taken since this would significantly increase the analysis time. As shown in one of our previous works [27], the set of system parameters affects the possibility of reliable detection of the analyte in samples. Therefore, we took into account the data obtained during a long-term study of the kinetics of the analytical signal in the wells of a microplate in this work.…”

“…However, not all solvents can be used in immunoassays, since they lead to inactivation of antibodies [25]. Previous work in the laboratory was based on the use of methanol at a concentration of 10-30% for the detection of hydrophobic analytes such as food dyes, phthalates, and mycotoxins by immunochemical techniques [26,27]. Therefore, this work is aimed at improving the analytical data obtained using the classical colorimetric and developed alternative approaches.…”

Phthalates: The Main Issue in Quality Control in the Beverage Industry

“…However, taking into the account their disadvantages related to the blank values, sensitivity, specificity, and expansive cost of instrumentation, a combination of detection systems based on magnetic material, noble metal nanoparticles, and aptamers have been successfully applied for the determination of PAEs [48]. For example, immunoassay techniques such as the enzyme-linked immunosorbent assay (ELISA) and fluorescent polarization immunoassay (FPIA) have been applied for the detection of BBP, DiBP, and DEHP in food and environmental samples [49][50][51][52]. In addition, molecular imprinting technology based on the use of amphiphilic magnetic adsorbents (e.g., Fe 3 O 4 -GPS-A, Fe 3 O 4 @MIPs@Ag, and Fe 3 O 4 @NIPs@Ag) have been investigated for the determination of DBP, DOP, and DMP in environmental samples [53,54].…”