Hi Fabio,

Boric acid and many borates are not very soluble in water at room temperature, but they become much more soluble in warm water.

Try to make your solution at 40-50 degC. It should work.

It is still possible that you'll get some precipitate when the solution cools back to room temperature. If so, look carefully at your reference article to see if they were working at "physiological" temperature - 37 degC - in which case most likely they wouldn't have seen a solid residue or precipitate.

I wouldn't recommend adding other chemicals. Many unexpected "side effects" are possible.

Good luck!

Emanuel Cooper

Hi Fabio,

Boric acid and many borates are not very soluble in water at room temperature, but they become much more soluble in warm water.

Try to make your solution at 40-50 degC. It should work.

It is still possible that you'll get some precipitate when the solution cools back to room temperature. If so, look carefully at your reference article to see if they were working at "physiological" temperature - 37 degC - in which case most likely they wouldn't have seen a solid residue or precipitate.

I wouldn't recommend adding other chemicals. Many unexpected "side effects" are possible.

Good luck!

Emanuel Cooper

hi

Preparation of Borate Buffer for Neuron Coating

Borate buffer is commonly used for coating culture surfaces to enhance neuronal attachment and improve cell survival in vitro. This buffer is often utilized in conjunction with Poly-D-Lysine (PDL) or Laminin to create a suitable environment for neuronal adhesion. Below is a step-by-step guide to preparing the appropriate borate buffer (0.1 M, pH 8.5) for neuron coating.

1. Required Materials

To prepare 0.1 M Borate Buffer (pH 8.5), you will need:

✅ Boric Acid (H₃BO₃): 6.18 g ✅ Sodium Hydroxide (NaOH) 1M: For pH adjustment ✅ Deionized Water (DI Water) ✅ pH Meter ✅ Graduated Cylinder or Pipette ✅ Magnetic Stirrer & Stir Bar (optional, for better mixing)

2. Preparation Steps for 0.1 M Borate Buffer (pH 8.5)

3. Using Borate Buffer for Neuron Coating

Borate buffer is commonly used as a solvent for Poly-D-Lysine (PDL) or Laminin when preparing culture surfaces for neuronal adhesion. The general steps are:

4. Important Notes

🔹 Precise pH Adjustment: Maintaining pH 8.5 is crucial for PDL efficiency. 🔹 Sterility: Filter the buffer before use if necessary. 🔹 Storage: Keep at 4°C and avoid freezing.

5. Summary

✅ Borate buffer (0.1 M, pH 8.5) is prepared using boric acid and NaOH. ✅ Used for neuron coating, typically with Poly-D-Lysine (PDL). ✅ Store at 4°C and filter for sterility if required.

This buffer improves neuron adhesion to culture surfaces and supports better cell survival in neuronal cultures.

good luck.

To prepare a borate buffer for neuron coating, begin by preparing stock solutions of boric acid and sodium tetraborate. Dissolve 6.18 g of boric acid (H₃BO₃) in 800 mL of distilled water and dissolve 10.01 g of sodium tetraborate (Na₂B₄O₇·10H₂O) in 200 mL of distilled water. Mix both solutions while stirring until completely dissolved.

Measure the pH using a calibrated pH meter and adjust accordingly. The borate buffer system allows for a pH range of 7.0 to 9.5, with higher pH values requiring the addition of more sodium tetraborate and lower pH values requiring more boric acid. Once the desired pH is reached, adjust the final volume to 1 liter with distilled water.

If the buffer is intended for cell culture applications, sterilization is recommended. This can be done by filtering the solution through a 0.22 µm filter to ensure sterility. Store the buffer at 4°C for optimal stability.

For neuron coating applications, borate buffer is commonly used to prepare poly-L-lysine (PLL) or poly-D-lysine (PDL) solutions. These coating solutions help promote cell adhesion and neuron survival. To coat culture surfaces, PLL or PDL is diluted in borate buffer at pH ~8.5 and incubated at 37°C for 1-2 hours or overnight at 4°C. After incubation, the coated surfaces should be washed with sterile PBS before seeding neurons. Proper preparation and handling of the buffer help ensure reproducible and stable neuron cultures.