In this thesis, the development of a novel paper-based capillary electrophoresis (pCE) microdevice using mineral paper is presented. The mineral paper is durable, oil and tear resistant, and waterproof. Thus, this material is better than quartz, glass or polymer in terms of facile chip fabrication, cost-effectiveness, and disposability. In this context, I presented the pCE microdevice without using an expensive and complicated conventional photolithography method. The pCE device consists of six layers: from top to bottom, PDMS reservoirs, an overhead projector (OHP) cover, a double-sided adhesive film layer, a micropatterned mineral paper layer, a double-sided adhesive film layer, and an OHP film. In the mineral paper, the typical cross-CE microchannel was patterned by using a cutting plotter, and the whole process for chip fabrication was completed in 1 hour. By conducting the applied voltages in the sample, waste, cathode, and anode reservoirs, the DNA could be injected, back-biased, and separated. In 2.9 cm separation channel, the DNA molecules with 4 bp difference in length were clearly separated. Moreover, two foodborne pathogen genes (rrsH of Escherichia coli O157:H7 and glnA of Staphylococcus aureus) were amplified, and the resultant amplicons (121 bp of rrsH and 225 bp of glnA) were distinguished on the pCE microdevice within 3 min. To assign the target peak in the electropherogram with high accuracy, two bracket ladders (80 bp and 326 bp) were used, so the target gene peaks could be exactly verified regardless of CE conditions. Such a pCE microdevice would be an ideal platform for DNA separation with high simplicity, speed, and accuracy in a resource-limited environments.
본 학위논문에서는 식중독균 검출을 위한 새로운 종이기반 모세관 전기영동 마이크로 디바이스를 개발하였다. 물과 오일에 젖지 않으며, 잘 찢어지지 않는 특성이 있는 미네랄 종이를 이용하여 비싸고 복잡한 포토리소그래피 과정 없이 커팅 플로터를 사용하여 종이기반 모세관 전기영동 마이크로 디바이스를 1시간 이내에 쉽고 저렴하게 제작할 수 있었다. 종이기반 모세관 전기영동 마이크로 디바이스 상에서 전형적인 모세관 전기영동 과정(샘플의 주입, 백-바이어싱, 분리)을 수행하였으며 최소 4 염기쌍 차이의 단일가닥 유전자를 분리할 수 있었다. 게다가 정확한 타깃 유전자 분석을 위하여 브래킷 레더를 사용함으로써 서로 길이가 다른 대장균과 포도상구균의 유전자 증폭산물을 3분 이내에 정밀하게 구별할 수 있었다. 이러한 종이기반 모세관 전기영동 마이크로 디바이스는 제한된 환경에서 유전자 분리를 위한 이상적인 플랫폼이 될 것이라 기대된다.