We developed an enzyme-linked antibody-ssDNA aptamer sandwich (ELAAS) method to detect three adipokines for diagnosing type 2 diabetes. For this application, three different aptamers for retinol-binding protein-4 (RBP4), visceral adipose tissue-derived serpin (Vaspin), and nicotinamide phosphoribosyltransferase (Nampt/visfatin) were used as capturing probes, and enzyme-linked polyclonal antibodies were used for signal generation. The sensitivities of this method for all three proteins were enhanced by at least 20-fold to up to 68-fold higher than that of the surface plasmon resonance (SPR) system, which only uses aptamers as capturing probes. In addition, this assay method exhibited equal sensitivity in the detection of each adipokine spiked in diluted human serum. In particular, the detection limit for RBP4 was similar to that obtained by western blotting, as reported previously. The simplicity, reproducibility, and high sensitivity of the ELAAS method could allow it to be extensively utilized in field.
Bibliographical noteFunding Information:
This work was supported in part by both the Advanced Production Technology Development Program for Agriculture and Forestry in the Ministry for Food, Agriculture, Forestry and Fisheries, Republic of Korea and the Technical Transfer funded by the Small & Medium Business Administration (SMBA) (Project #S1071611). The authors thank Ms. Hye-Jin Hong at Korea University for her assistance in preparing reagents and technical help in performing the assays.
- ELAAS biosensor
- Type 2 diabetes
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering
- Materials Chemistry