Label-free homogeneous detection of immunoglobulin E by an aptameric enzyme subunit


We have developed an aptameric enzyme subunit (AES) for immunoglobulin E (IgE) sensing. AES is an artificial enzyme subunit constructed from two different aptamers and does not require any modification. Using the AES, the target molecule can be detected by measuring enzymatic activity in homogeneous solution. We connected IgE-binding aptamer and its complementary strand to split thrombin-inhibiting aptamer. The hybrid of these two oligonucleotides inhibited thrombin activity and it decreased in the presence of IgE. We were able to detect IgE by using this AES in homogeneous solution with a detection limit of 50 pmol.

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This work was supported by Industrial Technology Research Grant Program in 2006 from New Energy and Industrial Technology Development Organization (NEDO) of Japan.

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Correspondence to Kazunori Ikebukuro.

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Yoshida, W., Sode, K. & Ikebukuro, K. Label-free homogeneous detection of immunoglobulin E by an aptameric enzyme subunit. Biotechnol Lett 30, 421–425 (2008).

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  • Aptameric enzyme subunit
  • Enzyme-inhibiting aptamer
  • Protein detection
  • Immunoglobulin E