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• DNA Extraction


  A routine procedure used to isolate DNA from the nucleus of cells

  
• DNA Extraction


  1. Lysis

  2. Precipitation

  3. Purification

  
• Examples of Kits for DNA Extraction

  • Ready-to-use DNA Extraction Kits

  
• Ready-to-use DNA Extraction Kits


  • Facilitate the extraction of DNA from specific cell types or sample types

  
• Phenol-Chloroform Extraction


  1. Phenol denatures proteins

  2. Chloroform extracts DNA

  3. Nucleic acids (DNA and RNA) are more soluble in the aqueous phase, allowing their separation from proteins
• RNAse enzyme


  Catalyzes cleavage of RNA, leading to RNA degradation
• Cell Lysis Buffer


  Breaks open cells and releases their contents, including DNA, RNA, and proteins
• Proteinase K


  Breaks down proteins by hydrolyzing peptide bonds
• Salting-Out Method


  1. Ammonium acetate or sodium acetate is used to precipitate DNA

  2. Relies on the differential solubility of DNA in the presence of high salt concentrations
• Spin-Column DNA Extraction


  1. Lysate is applied in the spin column where it binds to the positively charged solid silica surface

  2. Washing buffer removes all other debris while the pure DNA elutes under the treatment of high pH and salt-containing elution buffer

  
• Spin-Column DNA Extraction: Lysis


  Proteinase K and lysis buffer are added to the sample to lyse proteins, lipids, and cellular debris

  
• Spin-Column DNA Extraction: Adsorption


  Lysate is transferred to a column where DNA, with its negative charge, binds to the positively charged silica gel matrix

  
• Spin-Column DNA Extraction: Washing


  Wash buffer (usually containing ethanol or isopropanol) removes debris from the column
• Spin-Column DNA Extraction: Elution


  High pH and salt elution buffers dissolve DNA by breaking the bond between DNA (negative charge) and silica (positive charge)

  
• Agarose Gel Electrophoresis


  A procedure used in molecular biology to separate and identify molecules (such as DNA and RNA) by size

  
• Agarose Gel Electrophoresis


  • Smaller molecules move faster than larger molecules through the gel
  • Higher concentrations of agarose result in smaller pore sizes, slowing down the migration of larger DNA fragments

  
• DNA ladder


  A mixture of DNA fragments of known sizes used as a reference in agarose gel electrophoresis

  
• DNA ladders typically consist of a series of DNA fragments ranging from a few hundred base pairs (bp) to several thousand base pairs in length
• Each fragment in the ladder has a defined size, allowing researchers to estimate the size of DNA fragments in their samples by comparing their migration distance to the ladder bands