Label-free DNA detection using two-dimensional periodic relief grating as a visualized platform for diagnosis of breast cancer recurrence after surgery.
In this study we fabricated a nanopillar array of silicon oxide, involving very-large-scale integration (VLSI) and reactive ion etching (RIE), as two-dimensional periodic relief gratings (2DPRGs) on Si surfaces. Thiolated oligonucleotide was successively immobilized on the thiol functionalized surfaces of 2DPRGs by disulfide bond as an optical probe to detect a human genomic DNA (hgDNA584), related to breast cancer recurrence after surgery, from a biological specimen. The oligonucleotide-bound 2DPRG alone produces insignificant structure change, but upon hybridization with hgDNA584 leads to a dramatic change of the pillar scale due to hgDNA584 filling inside the 2DPRG layers. The performance of the sensor was evaluated by capturing hgDNA584 on the oligonucleotide-bound 2DPRGs and measuring the effective refractive index (neff), resulting of color change from pure blue to red, observed by naked eyes along an incident angle of 20-30°. The surface-bound 2DPRG based assay with the chemoresponsive diffraction grating signal transduction scheme results in an experimentally simple DNA detection protocol, displaying attributes of both detection methodologies: the high sensitivity and selectivity afforded by 2DPRG probes and the experimental simplicity, and miniaturization potential provided by the diffraction-based sensing technology.
Department of Materials Science and Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 106, Taiwan, ROC. Electronic address: jkchen@mail.ntust.edu.tw.
Jem-Kun
JK
Chen
Department of Materials Science and Engineering, National Taiwan University of Science and Technology, 43, Section 4, Keelung Road, Taipei 106, Taiwan, ROC.
Gang-Yan
GY
Zhou
Department of Chemical Engineering, Feng Chia University, 100, Wenhwa Road, Seatwen, Taichung 40724, Taiwan, ROC.
Chi-Jung
CJ
Chang
Department of Anatomy, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan, ROC.
Ai-Wei
AW
Lee
Department of Materials and Optoelectronic Science, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan, ROC.
Feng-Chih
FC
Chang
D015374:Biosensing Techniques / Q000295:instrumentation*; D001943:Breast Neoplasms / Q000175:diagnosis*; D004247:DNA / Q000032:analysis*; D004867:Equipment Design; D005260:Female; D006801:Humans; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D009693:Nucleic Acid Hybridization; D012031:Refractometry; D012680:Sensitivity and Specificity
D004247:DNA
DNA detection; Effective medium theory; Refractive index; Two-dimensional periodic grating