sodium-dodecyl-sulfate and ammonium-acetate

DNA is widely used in plant genetic and molecular biology studies. In this chapter, we describe how to extract DNA from wheat tissues. The tissue samples are ground to disrupt the cell wall. Then cetyltrimethylammonium bromide (CTAB) or sodium dodecyl sulfate (SDS) is used to disrupt the cell and nuclear membranes to release the DNA into solution. A reducing agent, β-mercaptoethanol, is added to break the disulfide bonds between the cysteine residues and to help remove the tanins and polyphenols. A high concentration of salt is employed to remove polysaccharides. Ethylenediaminetetraacetic acid (EDTA) stops DNase activity by chelating the magnesium ions. The nucleic acid solution is extracted with chloroform-isoamyl alcohol (24:1) or 6 M ammonium acetate. The DNA in aqueous phase is precipated with ethanol or isopropanol, which makes DNA less hydrophilic in the presence of sodium ions (Na+).

Topics: Acetates; Cetrimonium; Cetrimonium Compounds; Chemical Fractionation; Chemical Precipitation; Chromosome Mapping; Cloning, Molecular; DNA, Plant; Edetic Acid; Genomics; Mercaptoethanol; Reducing Agents; Sodium Dodecyl Sulfate; Triticum

Fundamental studies on the nanopreparation of neutral analytes in CZE by analyte focusing by micelle collapse (AFMC) are presented. The background solution (BGS) is prepared using an electrolyte salt (i.e. sodium or ammonium acetate). The sample solution of the neutral analytes (S) is prepared using SDS at a concentration above the cmc. To induce AFMC, the conductivity of the S must be greater than the BGS. This was achieved by the addition of the electrolyte salt to the S. Dilution of the micellar carrier from the injected S occurs at the BGS zone closest to the boundary between the S and BGS (micellar dilution zone). The dilution of SDS below the cmc causes the collapse of the micelles with subsequent release of previously bound analyte molecules. The continued transport and release causes the analytes to be accumulated at the micellar dilution zone. This nanopreparative technique is compatible with detection using mass spectrometry and can be utilized as a sample injection step for microfluidic devices. The disadvantage of this technique is that the neutral analytes are not separated after concentration. Here, the effect of retention factor of the analyte, conductivity ratio of the S and BGS, SDS concentration in the S, electrolyte salt (i.e. sodium acetate) concentration in the BGS, and organic modifier content in the BGS were examined. A study on the effect of the sample matrix injection prior to the sample injection to the performance of AFMC-CZE to neutral analytes is also presented.

Topics: Acetates; Electrolytes; Electrophoresis, Capillary; Methanol; Micelles; Nanotechnology; Sodium Acetate; Sodium Dodecyl Sulfate

Effective isocratic separations of decongestants and antihistamines is a challenging analytical task due to wild differences in their lipohilicities (hydrophilic decongestants and hydrophobic antihistamines). In this paper a new approach for resolving such a problem is described taking pseudoephedrine sulfate and loratadine as an example. The chromatographic behavior of pseudoephedrine sulfate and loratadine on RP C18 and C8 columns were studied in presence and absence of sodium lauryl sulfate (SLS). The effect of combining two different types of stationary phases (cyano and C18 or C8) on the relative retention of the two compounds was investigated. In conclusion, it was found that the combination of a C18 column followed by a standard cyano column provides a stationary phase that separates both compounds effectively and within a reasonable time. This approach was compared to a literature method and demonstrated to have superior selectivity.

Topics: Acetates; Buffers; Calibration; Chromatography, High Pressure Liquid; Ephedrine; Hydrogen-Ion Concentration; Hydrophobic and Hydrophilic Interactions; Loratadine; Reproducibility of Results; Sodium Dodecyl Sulfate; Solubility; Tablets; Technology, Pharmaceutical; Water