Synergistic effect of orientation and lateral spacing of protein G on an on-chip immunoassay.
SCIE
SCOPUS
- Title
- Synergistic effect of orientation and lateral spacing of protein G on an on-chip immunoassay.
- Authors
- Kim, EungSam; Shim, ChangKyoon; Lee, Jae W; Park, JW; Choi, KY
- Date Issued
- 2012-04
- Publisher
- Royal Society of Chemistry
- Abstract
- The proper orientation and lateral spacing of antibody molecules are a crucial element for an on-chip immunoassay in which the antibody or its antigen-binding fragments are immobilized on a solid surface. We covalently immobilized a modified protein G (Cys-protein G: protein G with only an N-terminal cysteine) on a dendron-coated surface to control its orientation and lateral spacing simultaneously. The cysteine-specific immobilization of Cys-protein G through the N-terminal cysteine resulted in 2.2-fold higher binding efficiency of Cys-protein G to IgG(2a) capture antibody than its random immobilization via lysine residues. The lateral spacing of 3.2 nm due to the surface modification with the 9-acid dendron molecule contributed to a 1.5-fold increase in the antibody-binding ability of Cys-protein G. Topographic images of atomic force microscopy exhibited a uniform coverage of Cys-protein G molecules immobilized on the thiol-reactive 9-acid dendron surface and homogeneous distribution of antibody bound to Cys-protein G. In the sandwich immunoassay, the control of the orientation of Cys-protein G led to 10-fold higher detection capability for rIL-2 compared with the randomly oriented protein G. The synergistic advantage of the unidirectional orientation and homogeneous lateral spacing of Cys-protein Gs on the dendron-coated surface can be applied to the development of more sensitive and reproducible antibody microarrays.
- URI
- https://oasis.postech.ac.kr/handle/2014.oak/16437
- DOI
- 10.1039/C2AN16137K
- ISSN
- 0003-2654
- Article Type
- Article
- Citation
- Analyst, vol. 137, no. 10, page. 2421 - 2430, 2012-04
- Files in This Item:
-
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.