10x Sodium Citrate Buffer Recipe: A Comprehensive Guide
Introduction
Sodium citrate buffer is a commonly used buffer solution in molecular biology and biochemistry. It is used to maintain the pH of a solution at a specific range, usually between pH 6.5 to 7.5. In this article, we will provide a recipe for preparing a 10x sodium citrate buffer solution.
Reagents
The following reagents are required to prepare the 10x sodium citrate buffer solution:
- Sodium citrate dihydrate (C6H5O7Na2·2H2O): 29.4 g
- Distilled water: 100 mL
Protocol
- Weigh the sodium citrate dihydrate: Accurately weigh 29.4 g of sodium citrate dihydrate using a balance.
- Dissolve the sodium citrate dihydrate: Add the weighed sodium citrate dihydrate to 100 mL of distilled water in a beaker.
- Stir until dissolved: Stir the mixture until the sodium citrate dihydrate is completely dissolved.
- Check the pH: Use a pH meter to check the pH of the solution. The pH should be around 6.5 to 7.5.
- Filter the solution: Filter the solution through a 0.2 μm filter to remove any impurities.
- Store the buffer: Store the 10x sodium citrate buffer solution at room temperature (25°C) or in a cold room (4°C) for up to 6 months.
Notes
- Autoclaving: The 10x sodium citrate buffer solution can be autoclaved at 121°C for 15 minutes to sterilize it.
- pH adjustment: If the pH of the solution is not within the desired range, it can be adjusted using hydrochloric acid (HCl) or sodium hydroxide (NaOH).
- Concentration: The 10x sodium citrate buffer solution can be diluted to a working concentration of 1x (0.1 M) or 5x (0.5 M) as needed.
Troubleshooting
- Insoluble particles: If insoluble particles are observed in the solution, filter it through a 0.2 μm filter again.
- Contamination: If the solution becomes contaminated, prepare a fresh batch of the buffer solution.
- pH drift: If the pH of the solution drifts over time, prepare a fresh batch of the buffer solution.
By following this recipe, you can prepare a 10x sodium citrate buffer solution that can be used for various molecular biology and biochemistry applications.
