• JSTS:Journal of Semiconductor Technology and Science
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• v.1 no.4
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• pp.232-238
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• 2001

A new DNA purification chip is proposed and fabricated for the sample preparation of Nucleic Acid (NA) probe assay. The proposed DNA purification chip is fabricated using photosensitive glass substrate and polydimethylsiloxane (PDMS) cover fixture. We have successfully captured and eluted the DNA using the fabricated photosensitive glass chip. The fabricated DNA purification chip showed a binding capacity of $15ng/\textrm{cm}^2$and a minimum extractable input concentration of $100copies/200\muL$. The proposed DNA purification chip can be applied for low-cost, disposable sample preparation of NA probe assays.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.12
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• pp.1785-1791
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• 2010

This paper describes a separable microfluidic device fabricated with PDMS (polydimethylsiloxane) and glass. The device is used for sample preparation involving cell lysis and the DNA purification process. The cell lysis was performed for 2 min at $80^{\circ}C$ in a serpentine-type microreactor ($20 {\mu}l$) using a Au microheater that was integrated with a thermal microsensor on a glass substrate. The DNA that was mixed with other residual products during the cell lysis process was then filtered through a new filtration system composed of microbeads (diameter: $50 {\mu}m$) and PDMS pillars. Since the entire process (sample loading, cell lysis reaction, DNA purification, and sample extraction) was performed within 5 min in a microchip, we could reduce the sample preparation time in comparison with that for the conventional methods used in biochemistry laboratories. Finally, we verified the performance of the sample preparation chip by conducting PCR (polymerase chain reaction) analysis of the chip product.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1166-1172
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• 1998

A method for the isolation and purification of DNA from a red algae, Porphyra was innovated. The innovation of the method consists mainly of three steps that include sodium acetate treatment, chloroform extraction, and 0.2 volume isopropanol precipitation step. The sodium acetate treatment was designed to remove polysaccharide contamination, and the isopropanol step to remove proteins and salts contaminents. Genomic DNA,s of several species(for example, P. tenera, P. yezoensis, P. seriata, and P. pseudolinearis) was successfully isolated by the innovated method. The amount of DNA purified from one g of sample material with the innovated method was 53 g in average. The resulting DNA was characterized to include high molecular weight and showed no nuclease activity. The DNA was pure enough to be digested directly by various restriction enzymes without any difficulties. Porphyra DNA was pure enough and adequate for amplification reaction through the polymerase chain reaction (small nuclear rDNA PCR amplification).

• Analytical Science and Technology
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• v.21 no.4
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• pp.338-343
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• 2008

Extraction of DNA from skeletal material is of great importance in the identification of human remains, but is particularly difficult because the high amount of microbial DNA was often co-extracted with human bone DNA. We found that a phenol/chloroform extraction, followed by ultrafiltration, and cleanup by via the $QIAquick^{(R)}$ PCR purification kit yields higher amounts of human genomic DNA compared with extraction by the column affinity $method^{(R)}$ alone. Ultrafiltration extraction of human DNA from ten exhumed bone samples yielded $0.041-1.120ng/{\mu}L$ DNA (mean = $0.498ng/{\mu}L$ DNA), and purification using the column affinity resulted in $0.016-0.064ng/{\mu}L$ DNA (mean = $0.034ng/{\mu}L$ DNA). Although the STR genotyping by the column affinity method was partially successful, all DNA samples by the ultrafiltration method produced full profiles from the multiplex PCR. The efficiency of STR genotyping was in accordance with the amounts of the human DNA extracted.

• BMB Reports
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• v.31 no.6
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• pp.585-589
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• 1998

The herpes simplex virus type-1 (HSV-1)-encoded DNA polymerase consists of two subunits, the products of the UL30 and UL42 genes. UL30 and UL42 were coexpressed in Sf9 cells infected with recombinant baculoviruses carrying the two genes. The UL30 and UL42 gene products remained tightly associated throughout the purification, which led to a near homogeneous heterodimer composed of the DNA polymerase and UL42 protein. The DNA polymerase-UL42 protein heterodimer, purified from the recombinant baculovirus-infected Sf9 cells, showed the same high degree of processivity of deoxynucleotide polymerization as the enzyme purified from the HSV-1 infected primate cells. Like the latter, it contained a 3'-5' exonuclease activity that specifically hydrolyzes an incorrectly matched nucleotide at the 3' terminus of a primer, thereby contributing to the fidelity of DNA replication.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.2
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• pp.86-92
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• 2004

In this paper miniaturized disposable micro/nanofluidic components applicable to bio chip, chemical analyzer and biomedical monitoring system, such as blood analysis, micro dosing system and cell experiment, etc are reported. This system includes various microfluidic components including a micropump, micromixer, DNA purification chip and single-cell assay chip. For low voltage and low power operation, a surface tension-driven micropump is presented, as well as a micromixer, which was implemented using MEMS technology, for efficient liquid mixing is also introduced. As bio-reactors, DNA purification and single-cell assay devices, for the extraction of pure DNA from liquid mixture or blood and for cellular engineering or high-throughput screening, respectively, are presented.

• Journal of Microbiology
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• v.37 no.4
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• pp.234-242
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• 1999

To obtain the recombinant circumsporozoite (CS) protein for the diagnosis of patients and seroepidemiology of Plasmodium vivax malaria which have been prevalent in northern part of Kyonggido, the CS protein gene was amplified by the polymerase chain reaction (PCR) from genomic DNA of the Korean vivax malaria patient. The gene consists of 1,123 nucleotides except signal peptide sequences and had an uninterrupted reading frame encoding a protein of 374 amino acids with a central region of 20 tandem repeats of the nonapeptide. The CS protein gene was expressed in Escherichia coli and purified, the molecular weight of recombinant CS protein was about 44 kDa (monomer) under denaturing purification and about 65 kDa (dimer) under native purification by SDS-PAGE. The purified recombinant CS protein which has antigenicity to malaria patients in Western blot analysis and Enzyme-linked immunosorbent assay, reacted only with the serum of P. vivax (PV210) infected malaria patients with no cross reaction to the P. falciparum malaria patient. The recombinant CS protein purified in this study will serve as a useful antigen to support the diagnosis of malaria patients and seroepidemiology.

• Biomedical Science Letters
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• v.2 no.2
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• pp.231-240
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• 1996

Human blood clotting (coagulation) factor 9 cDNA which codes for 461 amino acid has been cloned by screening human fetal liver cDNA library using PCR. This 1.4 kb cDNA spanning from the ATG initiation codon to the TAA termination codon was cloned into bacterial .expression vector pGEX-2T, generating pGEX-F9 plasmid. The plasmid pGEX-F9 expresses about 73 kDa GST (Glutathione S-transferase)-Factor 9 fusion protein when introduced into E. coli. Western blot analysis using polyclonal antibody raised against human factor 9 confirmed this fusion protein contains factor 9 protein. The level of GST-factor 9 expression was about 20% of total protein and the purification of fusion protein was efficiently achieved by using GST agarose bead based on one step purification protocol.

• Journal of agriculture & life science
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• v.43 no.2
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• pp.31-38
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• 2009

The DNA sequencer is known to be more sensitive for the quality of template DNA, method of purification followed by sequencing reaction, and gel concentration. Therefore, we investigated optimal conditions for template preparation, purification, sequencing reaction, gel concentration, and injection medium. For plasmid prepara- tion, using chloroform instead of phenol improved the average read length from 532 bp to 684 bp. The addition of 2.5% DMSO sequencing PCR reaction resulted in 200 bp longer sequences. Purification using 50 mM EDTA and 0.6 M Sodium acetate(pH 8.0) presented 20 bp longer sequences than that using 50 mM EDTA(pH 8.0) and 0.6 M sodium acetate(pH 5.2). The injection for sequencing analysis using ABI formamide presented 90 bp longer sequences than that of using formamide deionized by resin. Moreover, there were 150 bp more readable sequences in 3.6% PAGE gel than in 4%. Consequently, it was concluded that an average of 700 bp per reaction with 85% accuracy can be obtained by the following optimal conditions: template preparation using chloroform, 2.5% DMSO, 50 mM EDTA and 0.6 M sodium acetate(pH 8.0), ABI formamide and 3.6% gel concentration.

• Journal of Microbiology
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• v.35 no.4
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• pp.354-359
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• 1997

Methods for the extraction of DNA from water sample were approximated. Four different procedures of DNA extraction were carried out with pellets obtained from centrifugation of 4 liter water samples. The recovery efficiency and purity of DNA extracted by each method from different sources were compared. DNA yield varied with extraction methods, Method I, which involves enzymatic and freeze-thaw lysis steps and phenol and phenol-chloroform purification of extracted nucleic acid, showed a significantly higher yield and purity than the other methods. The use of glass beads in the DNA extraction methods improved the purity of DNA suitable for PCR. Bovine serum albumin in the PCR reaction mixture was useful in reducing inhibitory effects of contaminants. The efficiency of an extraction method was determined by the detection of the aer of Aeromonas hydrophila with PCR. The lower limit of detection of A. hydrophila from seeded tap water was 2 CFU/ml in PCR when method I was used for DNA preparation.