Physicochemical properties of nucleic acids

What you will learn

• Relate nucleic-acid size, density, charge, solubility, and viscosity to their structure.
• Interpret UV absorbance measurements and purity ratios used after extraction.
• Explain denaturation, melting, renaturation, and hybridization of nucleic acids.
• Distinguish acid, alkaline, and enzymatic hydrolysis and their analytical applications.

Course outline

1. Reading properties from structure

   An introduction links the phosphodiester backbone, bases, and strand organisation to laboratory behaviour.

   12 min

2. Size, density, charge, solubility, and viscosity

   Each physical property is separately linked to its structural cause and experimental use.

   28 min

3. Ultraviolet absorption, quantification, and purity

   The 260 nm signal is studied separately as a base signature, a quantification tool, a purity check, and a pairing indicator.

   24 min

4. Denaturation and melting temperature

   Causes of strand separation, hyperchromic monitoring, and determinants of melting temperature are studied separately.

   26 min

5. Hybridisation, renaturation, and nucleic-acid probes

   Complementarity, cooling rate, DNA-RNA hybrids, and probe recognition are explained as four distinct concepts.

   22 min

6. Acid hydrolysis

   Selective action of dilute acid on purines is distinguished from total destruction caused by heated strong acid.

   14 min

7. Alkaline hydrolysis of RNA and DNA resistance

   The role of 2′-OH, the cyclic intermediate, final products, and analytical use are explained step by step.

   22 min

8. Enzymatic hydrolysis and nuclease specificity

   Nucleases are classified separately by attack site, substrate, direction, recognised site, and phosphodiester cleavage type.

   32 min