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Isoelectric Point definitions

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  • Isoelectric Point

    Specific pH where a molecule's positive and negative charges are balanced, resulting in zero net charge.
  • pI

    Abbreviation for the pH at which a molecule exhibits no net charge, crucial for protein separation techniques.
  • Amino Acid

    Building block of proteins, each with unique side chains and characteristic pKa values affecting charge at different pH.
  • pKa

    Value indicating the pH at which a specific group on a molecule loses or gains a proton, used in pI calculations.
  • R Group

    Side chain of an amino acid, determining its properties; can be ionizable or non-ionizable, affecting pI calculation.
  • Non-Ionizable R Group

    Side chain that does not participate in ionization, simplifying pI calculation to averaging two pKa values.
  • Acidic Amino Acid

    Type of amino acid with lower pI values due to more acidic side chains, influencing net charge at various pH.
  • Basic Amino Acid

    Type of amino acid with higher pI values, attributed to basic side chains, affecting charge at different pH levels.
  • Electrophoresis

    Technique using electric fields to separate molecules based on net charge, with migration halted at pI.
  • Net Charge

    Sum of positive and negative charges on a molecule, reaching zero at the isoelectric point.
  • Neutral Species

    Form of a molecule where positive and negative charges are balanced, used in pI calculation.
  • Valine

    Amino acid with a non-ionizable R group, requiring only two pKa values for pI determination.
  • Protein

    Macromolecule composed of amino acids, whose net charge and pI are key for separation and identification.