Dundalk Institute of Technology 13
Introduction to Gel Preparation
Purpose: This section focuses on preparing and understanding the components involved in gel electrophoresis, specifically DNA visualization.
CyberSafe
Function: CyberSafe is added to the gel shortly after it has cooled to allow for visualization of DNA under UV light.
Binding: Binds to DNA, fluorescing to indicate the presence and separation of DNA.
Concentration:
Used in the preparation of 1x solution from a 10x stock solution:
Example ratio mentioned: 75 grams of gel requires a specific amount of CyberSafe, calculated from the 10x to 1x dilution.
TriTrac (Loading Buffer)
Role in Experiment:
Visualization Support: Although not visible with UV light, it tracks the progress of DNA through the gel.
Weighting Agent: Contains components (like glycine) that help weigh down DNA samples into the wells, preventing cross-contamination.
Concentration Explanation:
Generally, a 1 in 5 dilution is suggested for TriTrac:
Example: 1 uL of TriTrac for every 5 uL of sample.
DNA Ladder
Purpose: Used as a DNA marker, enabling estimation of DNA band sizes during electrophoresis.
Placement: Should be placed in one of the wells alongside the DNA samples to facilitate comparison.
Preparation Steps
Gel Cooling: After gel preparation, allow it to cool down before adding CyberSafe.
Adding Components:
After swirling the gel with the CyberSafe, ensure even distribution for fluorescence.
Calculation Reminder: Important to double-check the amount of each component (CyberSafe and TriTrac) required for the total gel volume (75 mL in this example).
Key Takeaways
Importance of CyberSafe: Forgetting to add CyberSafe means the DNA can separate but cannot be visualized, which is counterproductive to the experiment.
TriTrac and DNA Ladder: Both play crucial roles in ensuring that DNA samples can be monitored and accurately sized during the process.