1
|
Nguyen VD, Nguyen HQ, Bui KH, Ko YS, Park BJ, Seo TS. A handheld-type total integrated capillary electrophoresis system for SARS-CoV-2 diagnostics: Power, fluorescence detection, and data analysis by smartphone. Biosens Bioelectron 2022; 195:113632. [PMID: 34571485 DOI: 10.1016/j.bios.2021.113632] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 09/09/2021] [Accepted: 09/11/2021] [Indexed: 12/23/2022]
Abstract
A micro-capillary electrophoresis (μCE) system is one of the widely adopted techniques in the molecular diagnostics and DNA sequencing due to the benefits of high resolution, rapid analysis, and low reagent consumption, but due to the requirements of bulky high-power suppliers and an expensive laser-induced fluorescence detector module, the conventional set-up of μCE system is not adequate for point-of-care (POC) molecular diagnostics. In this study, we constructed a miniaturized and integrated μCE system which can be manipulated by a smartphone. The smartphone not only powers two boost converters and an excited laser, but also controls the relay for the power switch. Moreover, the complementary metal-oxide-semiconductor (CMOS) camera of the smartphone was used for detecting the fluorescence signal of amplicons amplified with reverse transcription-polymerase chain reaction (RT-PCR). We also developed a web-based application so that the raw data of the recorded fluorescence intensity versus the running time can display typical capillary electropherograms on the smartphone. The total size of the hand-held μCE system was 9.6 cm [Width] × 22 cm [Length] × 15.5 cm [Height], and the weight was ∼1 kg, which is suitable for POC DNA testing. In the integrated smartphone-associated μCE system, we could accurately analyze two genes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), namely N gene and S gene along with two bracket ladders in 6 min to identify SARS-CoV-2. Such an advanced μCE platform can be applied for a variety of on-site molecular diagnostics fields with user-friendliness.
Collapse
Affiliation(s)
- Van Dan Nguyen
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, 1 Seochon-dong, Giheung-gu, Yongin-si, Gyeonggi-do, 17140, Republic of Korea
| | - Huynh Quoc Nguyen
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, 1 Seochon-dong, Giheung-gu, Yongin-si, Gyeonggi-do, 17140, Republic of Korea
| | - Khang Hoang Bui
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, 1 Seochon-dong, Giheung-gu, Yongin-si, Gyeonggi-do, 17140, Republic of Korea
| | - Young Soo Ko
- Department of Chemical Engineering and Department of Future Convergence Engineering, Kongju National University, Cheonan City, Chungcheongnam-do, Republic of Korea
| | - Bum Jun Park
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, 1 Seochon-dong, Giheung-gu, Yongin-si, Gyeonggi-do, 17140, Republic of Korea
| | - Tae Seok Seo
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, 1 Seochon-dong, Giheung-gu, Yongin-si, Gyeonggi-do, 17140, Republic of Korea.
| |
Collapse
|
2
|
Analysis of degraded casework DNA by redesigning a mini Y-STR multiplex. FORENSIC SCIENCE INTERNATIONAL GENETICS SUPPLEMENT SERIES 2017. [DOI: 10.1016/j.fsigss.2017.09.071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
3
|
Lee JW, Lee D, Kim YT, Lee EY, Kim DH, Seo TS. Low-cost and facile fabrication of a paper-based capillary electrophoresis microdevice for pathogen detection. Biosens Bioelectron 2017; 91:388-392. [DOI: 10.1016/j.bios.2016.12.053] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 12/20/2016] [Accepted: 12/23/2016] [Indexed: 11/26/2022]
|
4
|
Microfluidic Devices for Forensic DNA Analysis: A Review. BIOSENSORS-BASEL 2016; 6:bios6030041. [PMID: 27527231 PMCID: PMC5039660 DOI: 10.3390/bios6030041] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 07/07/2016] [Accepted: 07/25/2016] [Indexed: 12/16/2022]
Abstract
Microfluidic devices may offer various advantages for forensic DNA analysis, such as reduced risk of contamination, shorter analysis time and direct application at the crime scene. Microfluidic chip technology has already proven to be functional and effective within medical applications, such as for point-of-care use. In the forensic field, one may expect microfluidic technology to become particularly relevant for the analysis of biological traces containing human DNA. This would require a number of consecutive steps, including sample work up, DNA amplification and detection, as well as secure storage of the sample. This article provides an extensive overview of microfluidic devices for cell lysis, DNA extraction and purification, DNA amplification and detection and analysis techniques for DNA. Topics to be discussed are polymerase chain reaction (PCR) on-chip, digital PCR (dPCR), isothermal amplification on-chip, chip materials, integrated devices and commercially available techniques. A critical overview of the opportunities and challenges of the use of chips is discussed, and developments made in forensic DNA analysis over the past 10–20 years with microfluidic systems are described. Areas in which further research is needed are indicated in a future outlook.
Collapse
|
5
|
Lee D, Kim YT, Lee JW, Kim DH, Seo TS. An integrated slidable direct polymerase chain reaction-capillary electrophoresis microdevice for rapid Y chromosome short tandem repeat analysis. KOREAN J CHEM ENG 2016. [DOI: 10.1007/s11814-016-0103-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
6
|
Total integrated slidable and valveless solid phase extraction-polymerase chain reaction-capillary electrophoresis microdevice for mini Y chromosome short tandem repeat genotyping. Biosens Bioelectron 2016; 78:489-496. [DOI: 10.1016/j.bios.2015.11.079] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 11/17/2015] [Accepted: 11/26/2015] [Indexed: 11/21/2022]
|
7
|
Kim YT, Heo HY, Oh SH, Lee SH, Kim DH, Seo TS. Microchip-based forensic short tandem repeat genotyping. Electrophoresis 2015; 36:1728-37. [DOI: 10.1002/elps.201400477] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Revised: 03/06/2015] [Accepted: 04/20/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Yong Tae Kim
- Department of Chemical and Biomolecular Engineering (BK21 plus program), Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Hyun Young Heo
- Department of Chemical and Biomolecular Engineering (BK21 plus program), Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Shin Hye Oh
- DNA Analysis Laboratory, Division of Forensic DNA; Supreme Prosecutors’ Office; Seoul Republic of Korea
| | - Seung Hwan Lee
- DNA Analysis Laboratory, Division of Forensic DNA; Supreme Prosecutors’ Office; Seoul Republic of Korea
| | - Do Hyun Kim
- Department of Chemical and Biomolecular Engineering (BK21 plus program), Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Tae Seok Seo
- Department of Chemical and Biomolecular Engineering (BK21 plus program), Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| |
Collapse
|
8
|
Hendrickx S, de Malsche W, Cabooter D. An overview of the use of microchips in electrophoretic separation techniques: fabrication, separation modes, sample preparation opportunities, and on-chip detection. Methods Mol Biol 2015; 1274:3-17. [PMID: 25673478 DOI: 10.1007/978-1-4939-2353-3_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This chapter is intended as a basic introduction to microchip-based capillary electrophoresis to set the scene for newcomers and give pointers to reference material. An outline of some commonly used setups and key concepts is given, many of which are explored in greater depth in later chapters.
Collapse
Affiliation(s)
- Stijn Hendrickx
- Department of Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, KU Leuven, O&N2 923, Herestraat 49, 3000, Leuven, Belgium
| | | | | |
Collapse
|
9
|
Ge Z, Wang W, Yang C. Rapid concentration of deoxyribonucleic acid via Joule heating induced temperature gradient focusing in poly-dimethylsiloxane microfluidic channel. Anal Chim Acta 2014; 858:91-7. [PMID: 25597807 DOI: 10.1016/j.aca.2014.12.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 12/09/2014] [Indexed: 10/24/2022]
Abstract
This paper reports rapid microfluidic electrokinetic concentration of deoxyribonucleic acid (DNA) with the Joule heating induced temperature gradient focusing (TGF) by using our proposed combined AC and DC electric field technique. A peak of 480-fold concentration enhancement of DNA sample is achieved within 40s in a simple poly-dimethylsiloxane (PDMS) microfluidic channel of a sudden expansion in cross-section. Compared to a sole DC field, the introduction of an AC field can reduce DC field induced back-pressure and produce sufficient Joule heating effects, resulting in higher concentration enhancement. Within such microfluidic channel structure, negative charged DNA analytes can be concentrated at a location where the DNA electrophoretic motion is balanced with the bulk flow driven by DC electroosmosis under an appropriate temperature gradient field. A numerical model accounting for a combined AC and DC field and back-pressure driven flow effects is developed to describe the complex Joule heating induced TGF processes. The experimental observation of DNA concentration phenomena can be explained by the numerical model.
Collapse
Affiliation(s)
- Zhengwei Ge
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 639798, Singapore
| | - Wei Wang
- Singapore Institute of Manufacturing Technology, 638075, Singapore
| | - Chun Yang
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, 639798, Singapore.
| |
Collapse
|
10
|
Chung S, Cho M, Hwan Jung J, Seok Seo T. Highly sensitive detection of cancer cells based on the DNA barcode assay and microcapillary electrophoretic analysis. Electrophoresis 2014; 35:1504-8. [DOI: 10.1002/elps.201400001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 02/07/2014] [Accepted: 02/08/2014] [Indexed: 11/12/2022]
Affiliation(s)
- Soyi Chung
- Department of Chemical and Biomolecular Engineering (BK21 Program); Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Minkyung Cho
- Department of Chemical and Biomolecular Engineering (BK21 Program); Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Jae Hwan Jung
- Department of Chemical and Biomolecular Engineering (BK21 Program); Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Tae Seok Seo
- Department of Chemical and Biomolecular Engineering (BK21 Program); Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| |
Collapse
|
11
|
Integration of sample pretreatment, μPCR, and detection for a total genetic analysis microsystem. Mikrochim Acta 2013. [DOI: 10.1007/s00604-013-1128-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
12
|
Kim YT, Choi JY, Chen Y, Seo TS. Integrated slidable and valveless polymerase chain reaction–capillary electrophoresis microdevice for pathogen detection. RSC Adv 2013. [DOI: 10.1039/c3ra41402g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
13
|
Olasagasti F, Ruiz de Gordoa JC. Miniaturized technology for protein and nucleic acid point-of-care testing. Transl Res 2012; 160:332-45. [PMID: 22683416 PMCID: PMC7104926 DOI: 10.1016/j.trsl.2012.02.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 02/22/2012] [Accepted: 02/24/2012] [Indexed: 01/26/2023]
Abstract
The field of point-of-care (POC) testing technology is developing quickly and producing instruments that are increasingly reliable, while their size is being gradually reduced. Proteins are a common target for POC analyses and the detection of protein markers typically involves immunoassays aimed at detecting different groups of proteins such as tumor markers, inflammation proteins, and cardiac markers; but other techniques can also be used to analyze plasma proteins. In the case of nucleic acids, hybridization and amplification strategies can be used to record electromagnetic or electric signals. These techniques allow for the identification of specific viral or bacterial infections as well as specific cancers. In this review, we consider some of the latest advances in the analysis of specific nucleic acid and protein biomarkers, taking into account their trend toward miniaturization and paying special attention to the technology that can be implemented in future applications, such as lab-on-a-chip instruments.
Collapse
Key Words
- poc, point-of-care
- lfi, lateral flow immunochromatography
- psa, prostate-specific antigen
- hcg, human chorionic gonadotropin
- tsh, thyroid-stimulating hormone
- seb, staphylococcal enterotixin b
- fret, förster resonance energy transfer
- mmp, matrix metalloproteinase 9
- bnp, b-type natriuretic peptide
- crp, c-reactive protein
- pdms, polydimethylsiloxane
- ig, immunoglobulin
- hb a1c, hemoglobin a1c
- ag, antigen
- ab, antibody
- tnfα, tumor necrosis factor α
- pct, procalcitonin
- il, interleukin
- pcr, polymerase chain reaction
- ca, cancer antigen
- cea, carcinoembryonic antigen
- nmp, nuclear matrix protein
- s100β, s100 calcium binding protein beta
- elisa, enzyme-linked immunosorbent assay
- vegf, vascular endothelial growth factor
- pmma, methyl methacrylate
- ctni, cardiac troponin i
- egf, epidermal growth factor
- ip, interferon-inducible
- mcp, monocyte chemoattractant protein
- timp-1, tissue inhibitor of matrix metalloproteinase-1
- rantes, regulated upon activation, normal t cell expressed and secreted
- mip-1 β, macrophage inflammatory protein-beta
- ctnt, cardiac troponin t
- hrp, horseradish peroxidase
- si-fet, silicon field-effect-transistor
- afp, alpha fetoprotein
- act, antichymotrypsin
- mia, magnetic immunoassay
- apc, allophycocyanin
- he4, human epididymis protein 4
- tmb, 3,3',5,5'-tetramethylbenzidine
- hp, hairpin
- lamp, loop-mediated isothermal amplification
- mrsa, methicillin resistant staphylococcus aureus
- fmdv, foot-and-mouth disease virus
- mμlamp, multiplex microfluidic lamp
- had, helicase-dependent amplification
- nasba, nucleic acid sequence based amplification
- lfm, lateral flow chromatography microarrays
- hsp, heat shock proteins
- spr, surface plasmon resonance
- mems, micro-electro-mechanical systems
- mimed, magnetic integrated microfluidic electrochemical detectors
Collapse
Affiliation(s)
- Felix Olasagasti
- Department of Biochemistry and Molecular Biology, Farmazia Fakultatea/Facultad de Farmacia, UPV-EHU, Gasteiz, Spain.
| | | |
Collapse
|
14
|
Jung JH, Choi SJ, Park BH, Choi YK, Seo TS. Ultrafast rotary PCR system for multiple influenza viral RNA detection. LAB ON A CHIP 2012; 12:1598-1600. [PMID: 22437437 DOI: 10.1039/c2lc21269b] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We presented a novel platform for an ultrafast PCR system, called the Rotary PCR Genetic Analyzer, which incorporates a thermal block and resistive temperature detector (RTD) for thermal cycling control, a disposable PCR microchip, and a stepper motor. The influenza viral RNAs from H3N2, H5N1, and H1N1 were simultaneously identified with high sensitivity and speed.
Collapse
Affiliation(s)
- Jae Hwan Jung
- Department of Chemical and Biomolecular Engineering (BK21 program) and Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Yuseong-gu, Daejeon, South Korea
| | | | | | | | | |
Collapse
|
15
|
Integrated microdevice of reverse transcription-polymerase chain reaction with colorimetric immunochromatographic detection for rapid gene expression analysis of influenza A H1N1 virus. Biosens Bioelectron 2012; 33:88-94. [PMID: 22265877 PMCID: PMC7126693 DOI: 10.1016/j.bios.2011.12.024] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2011] [Revised: 11/29/2011] [Accepted: 12/14/2011] [Indexed: 11/26/2022]
Abstract
An integrated microdevice of a reverse transcription-polymerase chain reaction (RT-PCR) reactor and an immunochromatographic strip was constructed for colorimetric detection of gene expression of influenza A virus subtype H1N1. An RT-PCR cocktail, which included Texas Red-labeled primers, dNTP including biotin-labeled dUTP, and RNA templates of influenza A H1N1 virus, was filled in the PCR chamber through the micropump, and the RT-PCR was performed to amplify the target H1 gene (102 bp). The resultant amplicons bearing biotin moieties and Texas Red haptens were subsequently eluted to the immunochromatographic strip, in which they were first conjugated with the gold nanoparticle labeled anti-hapten antibody in the conjugation pad, and then captured on the streptavidin coated test line through the biotin–streptavidin interaction. By observing a violet color in the test line which was derived from the gold nanoparticle, we confirmed the H1N1 target virus. The entire process on the integrated microdevice consisting of a micropump, a 2 μL PCR chamber, and an immunochromatographic strip was carried out on the portable genetic analyzer within 2.5 h, enabling on-site colorimetric pathogen identification with detection sensitivity of 14.1 pg RNA templates.
Collapse
|
16
|
Pascali JP, Bortolotti F, Tagliaro F. Recent advances in the application of CE to forensic sciences, an update over years 2009-2011. Electrophoresis 2011; 33:117-26. [DOI: 10.1002/elps.201100463] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
17
|
Jung JH, Kim GY, Seo TS. An integrated passive micromixer-magnetic separation-capillary electrophoresis microdevice for rapid and multiplex pathogen detection at the single-cell level. LAB ON A CHIP 2011; 11:3465-70. [PMID: 21870015 DOI: 10.1039/c1lc20350a] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Here we report an integrated microdevice consisting of an efficient passive mixer, a magnetic separation chamber, and a capillary electrophoretic microchannel in which DNA barcode assay, target pathogen separation, and barcode DNA capillary electrophoretic analysis were performed sequentially within 30 min for multiplex pathogen detection at the single-cell level. The intestine-shaped serpentine 3D micromixer provides a high mixing rate to generate magnetic particle-pathogenic bacteria-DNA barcode labelled AuNP complexes quantitatively. After magnetic separation and purification of those complexes, the barcode DNA strands were released and analyzed by the microfluidic capillary electrophoresis within 5 min. The size of the barcode DNA strand was controlled depending on the target bacteria (Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella typhimurium), and the different elution time of the barcode DNA peak in the electropherogram allows us to recognize the target pathogen with ease in the monoplex as well as in the multiplex analysis. In addition, the quantity of the DNA barcode strand (∼10(4)) per AuNP is enough to be observed in the laser-induced confocal fluorescence detector, thereby making single-cell analysis possible. This novel integrated microdevice enables us to perform rapid, sensitive, and multiplex pathogen detection with sample-in-answer-out capability to be applied for biosafety testing, environmental screening, and clinical trials.
Collapse
Affiliation(s)
- Jae Hwan Jung
- Department of Chemical and Biomolecular Engineering (BK21 program), Korea Advanced Institute of Science and Technology (KAIST), Yuseong-gu, Daejeon, South Korea
| | | | | |
Collapse
|
18
|
Hampikian G, West E, Akselrod O. The Genetics of Innocence: Analysis of 194 U.S. DNA Exonerations. Annu Rev Genomics Hum Genet 2011; 12:97-120. [DOI: 10.1146/annurev-genom-082509-141715] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Greg Hampikian
- Department of Biology and Department of Criminal Justice, Boise State University, Boise, Idaho 83724;
| | - Emily West
- The Innocence Project, New York, New York 10013
| | | |
Collapse
|
19
|
Chen Y, Seo TS. PCR-free digital minisatellite tandem repeat genotyping. Electrophoresis 2011; 32:1456-64. [PMID: 21626523 DOI: 10.1002/elps.201100073] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 03/03/2011] [Accepted: 03/03/2011] [Indexed: 11/11/2022]
Abstract
We demonstrated a proof-of-concept for novel minisatellite tandem repeat typing, called PCR-free digital VNTR (variable number tandem repeat) typing, which is composed of three steps: a ligation reaction instead of PCR thermal cycling, magnetic bead-based solid-phase capture for purification, and an elongated sample stacking microcapillary electrophoresis (μCE) for sensitive digital coding of repeat number. We designed a 16-bp fluorescently labeled ligation probe which is complementary to a repeat unit of a biotinylated synthetic template mimicking the human D1S80 VNTR locus and is randomly hybridized with the minisatellite tandem repeats. A quick isothermal ligation reaction was followed to link the adjacent ligation probes on the DNA templates, and then the ligated products were purified by streptavidin-coated magnetic beads. After a denaturing step, a large amount of ligated products whose size difference was equivalent to the repeat unit were released and recovered. Through the elongated sample stacking μCE separation on a microdevice, the fluorescence signal of the ligated products was generated in the electropherogram and the peak number was directly counted which was exactly matched with the repeat number of VNTR locus. We could successfully identify the minisatellite tandem repeat number with only 5 fmol of DNA template in 30 min.
Collapse
Affiliation(s)
- Yuchao Chen
- Department of Chemical and Biomolecular Engineering (BK21 program) and Institute for the BioCentury, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | | |
Collapse
|