Development of a Secondary Antibody Thio-Functionalized Microcantilever Immunosensor and an ELISA for Measuring Ginsenoside Re Content in the Herb Ginseng

• Published in: Analytical chemistry (Washington) Vol. 84; no. 10; pp. 4327 - 4333
• Main Authors: Nan, Tiegui, Wu, Shangquan, Zhao, Hongwei, Tan, Weiming, Li, Zhaohu, Zhang, Qingchuan, Wang, Baomin
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.05.2012
• Subjects: Analytical chemistry; Animals; Antibodies, Monoclonal - chemistry; Antibodies, Monoclonal - immunology; Biosensors; Cattle; Chemistry; Chromatographic methods and physical methods associated with chromatography; Enzyme-Linked Immunosorbent Assay; Exact sciences and technology; Female; General, instrumentation; Ginsenosides - analysis; Ginsenosides - immunology; Goats; Haptens - chemistry; Haptens - immunology; Herbs; Immunoassay; Immunoglobulin G - immunology; Mice; Mice, Inbred BALB C; Miscellaneous; Monoclonal antibodies; Other chromatographic methods; Panax - chemistry; Serum Albumin, Bovine - chemistry; Serum Albumin, Bovine - immunology; Sulfhydryl Compounds - chemistry; Immunoglobulins; Chemical analysis; Bovine; Microsensor; Enzyme; Sample; HPLC chromatography; IgG; Immobilization; Serum albumin; Monoclonal antibody; Concentration; Chemical sensor; Enzyme immunoassay; Immunosensor; Vertebrata; Sensitivity; Mammalia; Biosensor; Artiodactyla; Inhibition; ELISA assay; Ungulata
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac203414z

Ginsenoside Re (GRe) is a major active component of the Chinese medicinal herb ginseng, Panax ginseng. A sensitive and specific monoclonal antibody (mAb), designated as mAb3D6, was generated with a GRe–bovine serum albumin conjugate as an immunogen. Microcantilever immunosensors (MCS), one modified with thiolated anti-GRe antibody and one modified with thiolated goat antimouse immunoglobulin G (IgG), were developed to detect the content of ginsenoside. The MCS immobilized with thiolated goat antimouse IgG had a better sensitivity than the MCS modified with thiolated anti-GRe antibody. The advantage of a secondary antibody thio-functionalized MCS was verified with the anti-paclitaxel mAb. An indirect competitive enzyme-linked immunosorbent assay (icELISA) was also established with mAb3D6. The concentration of analyte producing 50% inhibition and the working range of icELISA were 1.20 and 0.15–16.1 ng/mL, respectively. The icELISA had a cross-reactivity of 89% with ginsenoside Rg1 and less than 3% with other ginsenosides. The icELISA and MCS with thiolated secondary antibody were applied for the determination of GRe in ginseng samples, and the results agreed well with those determined by high-performance liquid chromatography.