Chemistry Chapter 12: Spectroscopy and Separations Flashcards
Technique to distinguish between enantiomers
Polarimetry. Enantiomers can only be differentiated by the direction in which they rotate plane-polarized light, which is assessed using a polarimeter.
Liquid-liquid extraction
(LLE) is a technique that can be used to separate metal complexes and other compounds. It’s also known as solvent extraction or partitioning. LLE is often used to purify metal ions, and it can also be used to extract metal complexes into an organic phase.
uses an organic phase and an aqueous phase
Detergents are
✅ Detergents are amphipathic (have both polar and nonpolar regions).
✅ Polar head = Water-soluble (hydrophilic).
✅ Nonpolar tail = Oil-soluble (hydrophobic).
✅ This dual nature allows detergents to remove grease and dirt in water.
Would you like an example of a specific detergent in action? 😊
Isoelectric focusing
is a technique used to separate proteins based on their isoelectric point (pI), which is the pH at which a protein has no net charge and stops migrating in an electric field.
Cation Exchange vs Anion Exchange
Cation exchange = attracts cations to the walls (anions elute first)
Anion exchange = attracts anions to the walls (cations elute first)
Affinity Chromatography
uses specific interactions between a ligand and a target molecule to purify proteins, enzymes, or nucleic acids. Let’s break it down step by step.
What Happens in SDS-PAGE Under Non-Reducing Conditions?
SDS (Sodium Dodecyl Sulfate) is a detergent that unfolds proteins and gives them a uniform negative charge, so they separate only by size.
Non-covalent interactions (hydrophobic, hydrogen bonding, ionic bonds) are disrupted, causing most multimeric proteins to dissociate into monomers.
BUT, disulfide bonds remain intact because no reducing agent (like β-mercaptoethanol or DTT) is present.
The molar absorptivity tells us what?
Molar absorptivity (ε) influences intensity, not the wavelength shift.
TLC
Thin layer chromatography
What is rf?
Retention factor
