Electrical quantitation of BK virus DNA based on integrated nanogap sensor

다국어 초록 (Multilingual Abstract)

The nanogap sensors are a sensitive tool for molecular diagnostics, but they have the drawback that quantitative analysis is difficult due to irregular conductivity. To overcome these drawbacks, we applied digital domain analysis to integrated nanogap sensors. BK Virus DNA was hybridized with gold nanoparticle (AuNP) and magnetic particles modified with DNA. AuNPs were separated from the hybridization structure and trapped in the nanogap via DEP forces. When AuNPs form a conducting bridge between nanogaps, we can obtained quantification information as ODP (On-Device-Percentage) through the electrical signal. In this study, we observed that the quantification curves vary by DNA-passivated AuNP or AuNP size. As a result, BKV virus DNA can be detected pM level.

목차 (Table of Contents)

• Abstract 1
• Chapter 1. Introduction 2
• Chapter 2. Theoretical Background 3
• 2.1 Fabrication of integrated nanogap sensor 3
• 2.1.1) Photolithography 3
• 2.2 Quantification method 8
• 2.2.1) Digital domain analysis 8
• 2.2.2) On-device-percentage (ODP) 9
• 2.3 Dielectrophoresis (DEP) 11
• 2.4 BK Virus (BKV) DNA 16
• 2.4.1) BK Virus 16
• 2.4.2) Application of DNA hybridization in biosensing 17
• 2.5 Preparation of gold nanoparticles and application 19
• 2.5.1) Gold nanoparticle 19
• 2.5.2) Synthesis of gold nanoparticles 20
• 2.5.3) Application of gold nanoparticle in biosensing 22
• Chapter 3. Experimental section 25
• 3.1 Materials and appartus 25
• 3.2 DEP Condition 27
• 3.3 Nanogap device surface modification 29
• 3.4 Preparation nanoparticles 31
• 3.4.1) Preparation magnetic particle 31
• 3.4.2) Synthesis of gold nanoparticles 34
• 3.4.3) DNA passivated AuNP 35
• 3.5 Hybridization nanoparticle probes with DNA 40
• Chapter 4. Result and Discussion 42
• 4.1 Electrical quantitation 42
• 4.1.1) Depend on DNA passivated AuNP 43
• 4.1.2) Depend on AuNP size 46
• 4.2 Detection of BKV 48
• 4.2.1) Detection of BKV ssDNA 48
• 4.2 Supporting data 50
• Chapter 5. Conclusion 52
• References 53
• Korean Abstract 58