Formula Adjustment Review

Here is a review of your proposed formula:

• Vitamin B3 (Niacinamide) 4%: This is within the recommended usage rate of 1-10% (5% recommended for general use, up to 10% for Safe-B3™ type). Vitamin B3 helps reduce wrinkles, redness, hyperpigmentation, adds moisture, strengthens the skin barrier, and can reduce oiliness. It works well with N-acetyl glucosamine.
• N-acetyl Glucosamine 4%: This is within the recommended usage rate of 1-8% and aligns with the suggestion to use 4% in combination with Niacinamide 2-4%. It acts as a whitening agent, helps remove dark spots, stimulates hyaluronic acid production for moisture, and can help reduce wrinkles. It is also effective for gentle exfoliation and can help reduce acne breakouts. It works effectively with Vitamin B3.
• Alpha Arbutin 2%: This is at the maximum recommended usage rate of 0.2-2% for whitening. Alpha Arbutin is a safe and effective skin brightening agent that reduces melanin production. It is important to mix it below 30°C and maintain the formula's pH between 3.5-6.5. Avoid mixing in formulations with a pH higher than 8 as it can break down into hydroquinone.
• Pro Polymer 1%: This is within the recommended usage rate of 0.5-5% (0.8% recommended for general gel texture). Pro Polymer is a gel-forming substance that helps create the desired texture. 1% should provide a good gel consistency, potentially slightly thicker than a general gel, which might be suitable depending on your preference.
• Pitera (Galactomyces Ferment Filtrate) 89%: This is a very high concentration, within the possible usage rate of 1-100%. Pitera nourishes and revitalizes the skin, leaving it smooth and hydrated. Note that using high doses might feel a bit greasy. It should be mixed below 40°C.

Overall Formula:

This formula combines several effective ingredients for skin brightening, anti-aging, and hydration. The percentages of Vitamin B3, N-acetyl Glucosamine, and Alpha Arbutin are within or at the upper limit of their recommended ranges for efficacy. The high concentration of Pitera (89%) is notable and while it can be used up to 100%, be mindful of the potential for a greasy feel. Ensure the final formula's pH is suitable for Alpha Arbutin (3.5-6.5).