Detection of Gliadin in Foods Using a Quartz Crystal Microbalance Biosensor That Incorporates Gold Nanoparticles
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- 作者：Pei-Tzu Chu ; Chih-Sheng Lin ; Wei-Jung Chen ; Chih-Feng Chen ; Hsiao-Wei Wen
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2012
- 出版时间：July 4, 2012
- 年：2012
- 卷：60
- 期：26
- 页码：6483-6492
- 全文大小：429K
- 年卷期：v.60,no.26(July 4, 2012)
- ISSN：1520-5118
文摘
This work develops a label-free gliadin immunosensor that is based on changes in the frequency of a quartz crystal microbalance (QCM) chip. A higher sensitivity was obtained by applying 25 nm gold nanoparticles (AuNPs) to the surface of a bare QCM electrode. Subsequently, chicken anti-gliadin antibodies (IgY) were immobilized directly on the AuNP-modified surface by cross-linking amine groups in IgY with glutaraldehyde. Experimental results revealed that the change in frequency exhibited when 2 ppm gliadin was bound to the AuNP-modified electrode was 35 Hz (48%) greater than that of the bare gold electrode. The linear dynamic range in 60% ethanol was from 1 脳 101 to 2 脳 105 ppb gliadin, and the calculated limit of detection (LOD) was 8 ppb. The entire detection process was completed in 40 min and was highly repeatable. Additionally, the AuNP-modified QCM system generated results in the detection of gliadin in 10 commercial food products that were consistent with those obtained using an AOAC-approved gliadin kit. In conclusion, the QCM platform provides a potential alternative means of ensuring that people with wheat allergies and celiac patients have access to gliadin-free food.