Adjusting Serum pH with Sodium Hydroxide

Adjusting the pH of a serum using sodium hydroxide (NaOH) is very different from making natural soap, so there is no need to wait for a long curing period like with soap.

Here's the explanation:

1. Difference between Soap Making and pH Adjustment:

   • Soap Making: This is a chemical reaction called saponification, where NaOH reacts with fats or oils to convert them into soap and glycerin. This reaction takes time to complete, and excess water evaporates during curing. Curing for a month allows the reaction to complete, the soap to harden, and makes it safer to use.
   • Serum pH Adjustment: This simply involves adding a small amount of a base solution (NaOH dissolved in water) to change the acidity/alkalinity of the serum to the desired level (typically around pH 4.5-5.5 for skin). It does not involve a large-scale chemical reaction like soap making.

2. Regarding NaOH Fumes: In soap making, the heat generated when mixing NaOH with water can produce some hot vapor and alkaline fumes initially. However, the "NaOH fumes" that require a month to dissipate during soap curing are not direct NaOH fumes but relate to the process of the soap hardening, the reaction completing, and water evaporating. When adjusting serum pH, we use a very dilute solution of NaOH in a very small amount, so there are no "NaOH fumes" that require waiting for months.

3. Using Serum After pH Adjustment: If you adjust the pH of the serum correctly using a dilute NaOH solution, adding small amounts and mixing well until the pH is stable and within the safe range for skin (you should measure it with an accurate pH meter or test strips), you can use it immediately. There is no need to wait for days or months. The key is controlling the amount of NaOH used and verifying the final pH.

4. Mixing NaOH with Water Before Use: It is absolutely necessary to dissolve NaOH in water to create a solution before adding it to the serum to adjust pH. Never use solid NaOH flakes or powder directly, as it is dangerous and difficult to control. When dissolving NaOH in water, heat is generated. You should let the solution cool down before use, but there is no need to let the solution sit for several days; it can be used as soon as it has cooled.

In Summary:

• Adjusting serum pH with NaOH does not require waiting for days or months like soap curing. It can be used as soon as the pH is adjusted and verified to be within the safe range for skin.
• You must always dissolve NaOH in water first, but the solution does not need to sit for days; it can be used once cooled.
• The most important thing is to handle NaOH with extreme caution (wear gloves, eye protection) and always measure the final pH of the serum to ensure it is within the safe range for skin (approx. 4.5-5.5). Using a serum with too high a pH can cause skin irritation or burns.