Generi Biotech - Compounds and Services for Molecular Biology

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  • CATALOGUE AND PRICELIST
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• Oligonucleotides
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  • Oligo Purification
  • Quality Control
  • CATALOGUE AND PRICELIST
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  • 3´ end modified oligos
  • 5´ end modified oligos
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• MY OLIGO
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  • MY OLIGO - Demo
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Oligonucleotide Quality Control

MALDI-TOF spectrometry is used to check the oligonucleotides quality as a standard method, and HPLC (trityl-off) analysis is performed for an additional fee.

1) MALDI-TOF mass spectrometry

MALDI-TOF (Matrix Assisted Laser Desorption/Ionization - Time Of Flight) is an analytical method based on laser ionization of the analyte (oligonucleotide) molecules with the matrix assistance, subsequent measurement of the fly-through time of ionized molecules through the fly tube, and determining of the corresponding molecular mass. The synthesized sequence quality can be determined with high accuracy (i.e. whether the measured molecular mass corresponds to the calculated molecular mass) as well as the nature of any possible impurities based on mass spectra evaluation.

Examples of MALDI-TOF spectrograms >>

MALDI-TOF analysis is standardly performed with a representative sample of oligonucleotides of each synthesis run, and with all oligos where there is a risk of lower quality (for example, with modified oligos). The customer is not informed of these analyses.

2) HPLC analysis

Upon assignment of HPLC (trityl-off) analysis, the oligonucleotide quality is verified based on the size of the molecular negative charge. The resulting chromatogram provides an overview of the presence of chains with unfinished synthetization and other undesirable products of the synthesis. In the case of labelled or otherwise modified oligos, the chromatogram unveils the presence of unlabelled chains.

Examples of HPLC chromatograms >>

HPLC quality contol can be ordered for an additional fee of EUR 10. The chromatogram record with description of the peaks is supplied together with the oligonucleotides.

One additional fee is charged for every checked oligonucleotide. The fee is the same for all delivery terms, labelling or other modifications. HPLC quality control is automatically performed for no additional charge when HPLC oligo purification is ordered.

Purchase order

Please specify the oligonucleotide quality control type in the purchase order form.