Move beyond paper models and investigate DNA structure directly!

• Techniques: Micropipetting, fluorescence detection
• Topics: DNA structure, hydrogen bonds, fluorescence, biotechnology
• Time required: Can be completed in one or two 45-minute class periods
• Level: General high school through college

Discover the conditions that make double-stranded DNA denature into single strands, then anneal back together again. In this lab, students will use a fluorescent dye to investigate the conditions that influence DNA structure and its transition from double helix to single strand, and vice versa. Inquiry-based investigations explore how DNA sequence, concentration, and pH affect base pairing through hydrogen bonds.

Required equipment (one per lab group):
- Micropipettes and tips
- Thermal cycler or heat block that can accommodate PCR tubes (ideal set up) or water bath and floaties (workable).
- P51™ Molecular Viewer or other blue light transilluminator (such as blueBox™ or blueGel™)

Storage notes:
- Reagents require refrigerator storage
- DNA binding dye must be protected from light
- Reagents are stable for 6 months when stored in the refrigerator and protected from light