Oral Presentation 2-06

CONSTRUCTION OF ANTIBODY-CONJUGATED
BACTERIAL MAGNETIC PARTICLES AND
APPLICATION TO BIOSENSORS

Reiko Sato, Haruko Takeyama, Tsuyoshi Tanaka, and Tadashi Matsunaga

Department of Biotechnology
Tokyo University of Agriculture and Technology
2-24-16, Naka-cho
Koganei, Tokyo 184-8588 Japan

Telephone: +81-42-388-7020; Fax: +81-42-385-7713; E-mail: tmatsuna@cc.tuat.ac.jp

A food allergy may be defined as an adverse reaction to particular allergenic components of food. Rapid detection and sensing of food allergens have been required in the production of allergen-free food. We present a novel immunoassay of allergenic components using alkaline phosphatase antibody (ALP-Ab) immobilized on bacterial magnetic particles (BMPs) to evaluate the biological activity of food allergens, such as ovalbumin, albumin, and lysozyme. BMPs served as an antibody carrier because the amount of antibody coupling with BMPs was about fourfold greater than that achieved with artificial magnetite particles of the same size. ALP-Ab was immobilized onto BMPs to monitor the formation of BMP aggregates by chemiluminescence. Luminescence intensity of the suspension decreased with the addition of antigens and also correlated with the concentration of the antigen. This method enabled many antigenic components in a food to be detected and sensed simultaneously.