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Nucleic Acid Columns Ion Exchange Chromatography The
separation of synthetic oligonucleotides of defined
length and sequence, and the separation of DNA restriction fragments are
required for modern genetic engineering and in molecular biology. The ion
exchange columns, HYDROCELL NS 1500 was developed specifically for the
purification of PCR products, short nucleic acids from two to forty or more
nucleotide residues and DNA restriction fragments of up to 1000 base pairs.
NS 1500 is produced from 10 µm of highly cross-linked PS-DVB beads with pore
diameter of 500 Å.
pBR322
and pUC18 / Hae III digest DNA markers were used as
model samples of DNA restriction fragments. At room temperature, these
fragments were efficiently resolved on a HYDROCELL nucleic acid column.
Excellent
separation was obtained in 15 minutes when the oligonucleotide
standard, oligothymidylic acid d(pT) 12-18 mer, was chromatographed using the nucleic acid column. The larger
oligonucleotide fragments can be purified by
adjustment of elution conditions. They require higher concentrations of salt
and longer times for elution. In addition to their use
in process monitoring and quality control analysis of proteins and enzymes, Non-Porous Anion Exchangers, DEAE NP10 and QA NP10 high-speed
columns are also suitable for the analysis of small nucleotides, oligonucleotides, and DNA fragments. High loading
capacity and low back pressure are the unique characteristics of these
columns. These characteristics allow the easy scale-up from analytical
to preparative separations. The sensitivity of non-porous anion
exchangers is better and retention time is shorter than NS 1500. It is
recommended for the trace analysis and rapid scanning of complex samples.
Ion-Pair Reversed Phase Chromatography Denaturing HPLC
(DHPLC) is an ion-pair reversed phase high performance liquid chromatography
(IP-RP-HPLC) at temperature 35° to 80°C. It can be used for DNA fragment
analysis, PCR quantification and cleanup before sequencing or cloning. DHPLC
can identify variation by detecting heteroduplex
formation between reannealed wild-type and mutant
PCR fragments. It is a method of the detection of mutation and genomic
variation that is amenable to a sequencing core environment.
____________________________________________________________________________ Carbon Nanotubes sorting and purifying
by Ion Exchange Chromatography Wrapping of
carbon tubes by synthetic single-stranded DNA was found that electrostatics
of the DNA-CNT hybrid depends on tube diameter and electronic properties, enabling nanotube
separation by anion exchange chromatography. Optical absorption and Raman
spectroscopy show that early fractions are enriched in the small diameter and
metallic tubes, where late fractions are enriched in the large diameter and
semiconducting tubes. The purification of semiconducting single- walled
carbon nanotubes (SWCNT) with a purity of 99% or
higher is important in the electronic industry. The purification of
semiconducting SWCNT from metallic SWCNT are related to hydrophilic and ligand density of anion exchange packing materials, column dimension and DNA-CNT hybrid. The following
are the comparison of conventional NS 1500 column to
CNT-NS 1500 column in the separation of single stranded synthetic oligonucleotides standard mixture. Hydrocell CNT-NS 1500
showed the longer and wider retention time in the separation of the same
standard sample of 12-18 mer of phosphated
oligothymidylic acid in the comparison with
conventional NS 1500 for oligonucleotides and DNA
fragment purification.. The relationship of
DNA-CNT hybrid and the characteristic of anion
exchange packing materials in the purify semiconducting single-walled carbon nanotubes are under investigation.
Conventional Hydrocell NS 1500
Column
Hydrocell CNT-NS 1500 Column |
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© Copyright 2002 BioChrom Labs,
Inc. All rights reserved. |
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