Maeng Joon-Ho, Lee Byung-Chul, Ko Yong-Jun, Cho Woong, Ahn Yoomin, Cho Nahm-Gyoo, Lee Seoung-Hwan, Hwang Seung Yong
Department of Biochemistry, Graduate School, Hanyang University, Ansan, Gyeonggi-do 426-791, Republic of Korea.
Biosens Bioelectron. 2008 Apr 15;23(9):1319-25. doi: 10.1016/j.bios.2007.11.019. Epub 2007 Dec 5.
Conventional immunoassays are labor intensive, expensive and time consuming and require large pieces of equipment for detection. Therefore, we have developed and characterized a novel immunoassay methodology comprised of microbeads and microbiochips. In this method, microbeads are used to filter and immobilize antibodies and an immuno-gold silver staining (IGSS) method is then used to amplify electrical signals that correspond to the bound antibodies. The chip used for this system is composed of an inexpensive and biocompatible polydimethylsiloxane (PDMS) layer over a Pyrex glass substrate that contains a platinum (Pt) microelectrode, which is used to detect the electrical signal in this system, the microelectrode is fabricated on the substrate and a microchannel and pillar-type microfilter is formed in the PDMS layer. A sandwich immunoassay approach was applied to detect alpha-fetoprotein (AFP), a cancer biomarker, using this system. The results of this study showed that the time required for a complete assay was reduced by 1h and a detection limit as low as 1 ng/mL was attained when this system used, which indicates that similar bead-based electrical detection systems could be used for the diagnosis of many forms of cancer.
传统免疫测定法劳动强度大、成本高且耗时，并且需要大型检测设备。因此，我们开发并表征了一种由微珠和微生物芯片组成的新型免疫测定方法。在该方法中，微珠用于过滤和固定抗体，然后使用免疫金银染色（IGSS）方法放大与结合抗体相对应的电信号。用于该系统的芯片由覆盖在派热克斯玻璃基板上的廉价且具有生物相容性的聚二甲基硅氧烷（PDMS）层组成，该基板包含一个铂（Pt）微电极，用于检测该系统中的电信号，微电极制作在基板上，并且在PDMS层中形成微通道和柱型微滤器。使用该系统采用夹心免疫测定法检测癌症生物标志物甲胎蛋白（AFP）。本研究结果表明，使用该系统时，完整测定所需时间减少了1小时，检测限低至1 ng/mL，这表明类似的基于微珠的电检测系统可用于多种癌症的诊断。
