Selective extraction of biomolecules using a bidirectional flow filter

We present a microfluidic device for selective separation and extraction of molecules based on their diffusivity. The separation relies on electroosmotically-driven bidirectional flows in which high diffusivity species experience a net-zero velocity, and lower diffusivity species are advected to a collection reservoir. The device can operate continuously and is suitable for processing low sample volumes. Using several model systems, we showed that the extraction efficiency of the system is maintained at more than 90% over tens of minutes, with a purity of more than 99%. We demonstrate the applicability of the device to the extraction of genomic DNA from short DNA fragments.

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Faculty Opinions recommendation of Chemical regulated production of cDNAs from genomic DNA fragments in plants.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1003967.174058 ◽

2002 ◽

Author(s):

Xing Wang Deng

Keyword(s):

Genomic Dna ◽

Dna Fragments

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Enzymatic amplification and characterization of large DNA fragments from genomic DNA

Gene ◽

10.1016/0378-1119(88)90094-7 ◽

1988 ◽

Vol 71 (1) ◽

pp. 211-216 ◽

Cited By ~ 9

Author(s):

Phouthone Keohavong ◽

Cindy C. Wang ◽

Rita S. Cha ◽

William G. Thilly

Keyword(s):

Genomic Dna ◽

Dna Fragments ◽

Enzymatic Amplification

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Tantalum and Niobium Selective Extraction by Alkyl-Acetophenone

Metals ◽

10.3390/met8090654 ◽

2018 ◽

Vol 8 (9) ◽

pp. 654 ◽

Cited By ~ 6

Author(s):

Moussa Toure ◽

Guilhem Arrachart ◽

Jean Duhamet ◽

Stephane Pellet-Rostaing

Keyword(s):

Extraction Efficiency ◽

Methyl Isobutyl Ketone ◽

Selective Extraction ◽

Extraction Process ◽

Liquid Extraction ◽

Methyl Isobutyl ◽

Isobutyl Ketone ◽

Waste Solution ◽

Liquid Liquid Extraction ◽

D Values

A study has been carried out on Ta and Nb recovery by a liquid-liquid extraction process using 4-methylacetophenone (4-MAcPh) as the organic phase. The 4-MAcPh was compared to methyl isobutyl ketone (MIBK) with respect to extraction efficiencies (D values) at different concentrations of H2SO4 in the aqueous phase. The results showed a similar extraction of Nb for both solvents. However, for Ta, extraction efficiency is increased by a factor of 1.3 for 4-MAcPh. In addition, the MIBK solubilized completely after 6 mol∙L−1 of H2SO4 against only a loss of 0.14–4% for 4-MAcPh between 6 and 9 mol∙L−1 of H2SO4. The potential of 4-MAcPh has also been studied to selectively recover Ta from a model capacitor waste solution. The results showed a selectivity for Ta in the presence of impurities such as Ag, Fe, Ni and Mn. The 4-MAcPh also presents the advantage of having physicochemical properties adapted to its use in liquid-liquid extraction technologies such as mixer-settlers.

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Development of a fungal transformation system based on selection of sequences with promoter activity

Molecular and Cellular Biology ◽

10.1128/mcb.7.9.3297-3305.1987 ◽

1987 ◽

Vol 7 (9) ◽

pp. 3297-3305

Author(s):

B G Turgeon ◽

R C Garber ◽

O C Yoder

Keyword(s):

Genomic Dna ◽

Pathogenic Fungus ◽

Low Frequency ◽

Hygromycin B ◽

Fungal Transformation ◽

Dna Fragments ◽

Transformation System ◽

Chromosomal Dna ◽

General Utility ◽

Novel Strategy

A novel strategy was used to develop a transformation system for the plant pathogenic fungus Cochliobolus heterostrophus. Sequences capable of driving the expression of a gene conferring resistance to the antibiotic hygromycin B in C. heterostrophus were selected from a library of genomic DNA fragments and used, with the selectable marker, as the basis for transformation. The library of random 0.5- to 2.0-kilobase-pair fragments of C. heterostrophus genomic DNA was inserted at the 5' end of a truncated, promoterless Escherichia coli hygromycin B phosphotransferase gene (hygB) whose product confers resistance to hygromycin B. C. heterostrophus protoplasts were transformed with the library and selected for resistance. Resistant colonies arose at low frequency. Each colony contained a transformation vector stably integrated into chromosomal DNA. When the transforming DNA was recovered from the genome and introduced into C. heterostrophus, resistant colonies appeared at higher frequency. We determined the sequences of two of the C. heterostrophus DNA fragments which had been inserted at the 5' end of hygB in the promoter library and found that both made translational fusions with hygB. One of the two fusions apparently adds 65 and the other at least 86 amino acids to the N-terminus of the hygB product. Plasmids containing hygB-C. heterostrophus promoter fusions can be used unaltered to drive hygB expression in several other filamentous ascomycetes. This approach to achieving transformation may have general utility, especially for organisms with relatively undeveloped genetics.

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Identification of developmental regulatory genes in Aspergillus nidulans by overexpression.

Genetics ◽

10.1093/genetics/139.2.537 ◽

1995 ◽

Vol 139 (2) ◽

pp. 537-547 ◽

Cited By ~ 3

Author(s):

J F Marhoul ◽

T H Adams

Keyword(s):

Growth Inhibition ◽

Aspergillus Nidulans ◽

Genomic Dna ◽

Regulatory Gene ◽

Regulatory Genes ◽

Dna Fragments ◽

Expression Library ◽

Phenotypic Changes ◽

Inhibition Of Growth ◽

Induction Sequence

Abstract Overexpression of several Aspergillus nidulans developmental regulatory genes has been shown to cause growth inhibition and development at inappropriate times. We set out to identify previously unknown developmental regulators by constructing a nutritionally inducible A. nidulans expression library containing small, random genomic DNA fragments inserted next to the alcA promoter [alcA(p)] in an A. nidulans transformation vector. Among 20,000 transformants containing random alcA(p) genomic DNA fusion constructs, we identified 66 distinct mutant strains in which alcA(p) induction resulted in growth inhibition as well as causing other detectable phenotypic changes. These growth inhibited mutants were divided into 52 FIG (Forced expression Inhibition of Growth) and 14 FAB (Forced expression Activation of brlA) mutants based on whether or not alcA(p) induction resulted in accumulation of mRNA for the developmental regulatory gene brlA. In four FAB mutants, alcA(p) induction not only activated brlA expression but also caused hyphae to differentiate into reduced conidiophores that produced viable spores from the tips as is observed after alcA(p)::brlA induction. Sequence analyses of the DNA fragments under alcA(p) control in three of these four sporulating strains showed that in two cases developmental activation resulted from overexpression of previously uncharacterized genes, whereas in the third strain, the alcA(p) was fused to brlA. The potential uses for this strategy in identifying genes whose overexpression results in specific phenotypic changes like developmental induction are discussed.

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An End-Trimming Method and Its Application to Amplify Adjacent cDNA and Genomic DNA Fragments by PCR

PCR Cloning Protocols ◽

10.1385/0-89603-483-6:247 ◽

2003 ◽

pp. 247-260

Author(s):

Hiroyuki lwahana ◽

Mitsuo ltakura

Keyword(s):

Genomic Dna ◽

Dna Fragments

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LTCC 3D FLOW FOCALIZATION DEVICE FOR LIQUID-LIQUID PARTIAL SOLVENT EXTRACTION

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/2016cicmt-wa23 ◽

2016 ◽

Vol 2016 (CICMT) ◽

pp. 000111-000117

Author(s):

Houari Cobas Gomez ◽

Jéssica Gonçalves da Silva ◽

Jocasta Mileski Machado ◽

Bianca Oliveira Agio ◽

Francisco Jorge Soares de Oliveira ◽

...

Keyword(s):

Solvent Extraction ◽

Aqueous Phase ◽

Microfluidic Device ◽

Flow Rate ◽

Extraction Efficiency ◽

Channel Length ◽

Main Channel ◽

Process Variables ◽

3D Flow ◽

Acetone Concentration

Abstract The present work shows a ceramics microfluidic device for partial solvent extraction scheme. The technology used for device fabrication was Low Temperature Cofired Ceramics (LTCC) which allows us for complex and chemical resistant 3D microfluidic devices. The proposed system aims to partially extract the solvent present in a mixture containing aqueous and organic phases. This scheme uses a 3D flow focalization in order to improve the solvent diffusion into the external aqueous phase. The device is composed by three different parts, the input channels distribution, the main channel and the output channels distribution. The designed input channels distribution ensures a centered 3D focalized solvent stream along the main channel. The focalized solvent mixes with the surrounding water thanks to diffusion. Projected output channels take the central fluid out separately from the surrounding. Thus the device has two different outputs, one for the focalized fluid and another one for the waste fluid, which is the aqueous phase plus solvent. For a device concept proof, acetone and water were used as organic and aqueous phases, respectively. COMSOL Multiphysics was used for device microfluidics and chemical transport simulation. The extraction efficiency was the variable used as indicator for device performance validation. The flow rate ratio between phases, total flow rate, main channel length and focalized stream channel output hydraulic diameter (ODH) were used as process variables for simulation purposes. A factorial experimental planning was used in order to analyze the extraction efficiency taking into account process variables effects. From simulation results it was determined main channel length and ODH as the variables with stronger effect on extraction efficiency. Obtained simulated efficiencies were as high as 80.6%. Considering previous results observations a microfluidic device was fabricated with a main channel length of 21,4 mm and ODH of 214,63 μm. Gas chromatography was used to measured acetone concentration in outputs samples and from here the extraction efficiency. Experimental results were in agreement with simulation, returning extraction efficiencies in the order of 80.8% ± 2.2%.

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