Optimization and Surfactant Alternatives for Pre-wash Scalp Cleansing and Bond Repair Shampoos

Question

I am developing two shampoo formulations and would like a review and optimization of the surfactant systems.

1. Pre-wash Scalp Cleansing Shampoo

(Liquid, low-viscosity, applied to dry scalp, rinsed before regular wash. Goals: thorough cleansing, high tolerability, pleasant foaming on dry scalp).

Phase A: Aqua q.s. ad 100, Sodium Methyl Cocoyl Taurate (90% solids) 10.0% (heat to ~60°C in water until clear).
Phase B: Niacinamide 5.0%.
Phase C: Piroctone olamine 1.0% (pre-dissolved in 10% Ethanol if needed).
Phase D: Cocamidopropyl Betaine 2.0% OR Cond-Foam™ (Sodium Lauroyl Sarcosinate) 5.0-8.0%.
Phase E: PQ-7 0.2%.
Phase F: Sodium PCA (50%) 1.5%.
Phase G: Panthenol (75%) 1.5%.
Phase H: Gluconolactone 2.0%.
Phase I: Perfume oil 0.3% in Isopentyldiol 5.0% OR Polysorbate 20 1.0-1.5%.

2. Bond Repair Shampoo

(Hydrating formula).

Phase A: Aqua q.s., Sodium Methyl Cocoyl Taurate 10.0%.
Phase B: Niacinamide 5.0%.
Phase C: Itaconic Acid 0.15%.
Phase D: L-Arginine 0.1%.
Phase E: Bond repair blend 2.0%.
Phase F: PQ-7 0.2%.
Phase G: Sodium PCA (50%) 1.5%.
Phase H: Panthenol (75%) 1.5%.
Phase I: Cocamidopropyl Betaine 3.0% OR Cond-Foam™ 5.0-8.0%.
Phase J: Perfume oil 0.3% in Isopentyldiol 5.0% OR Polysorbate 20 1.0-1.5%.

Requests:

Review both formulations for corrections and improvements, specifically regarding the surfactant systems (stability, foaming, mildness, and viscosity).
Provide 3 variants for both products by replacing Sodium Methyl Cocoyl Taurate (10%) with:
- Variant 1: Gluta-Clean™ (Disodium Cocoyl Glutamate)
- Variant 2: AminoWash™ (Sodium Lauroyl Glutamate, Fine)
- Variant 3: Decyl Glucoside
  
  Please include optimal use levels and formulation tips.
Confirm if Gluta-Clean™, Decyl Glucoside, and Cond-Foam™ are self-preserving systems in these water-based formulations.

MySkinRecipes Expert · Accepted Answer

1. Formula Review & Optimization

Your base formulations for both the Pre-wash Scalp Cleansing Shampoo and the Bond Repair Shampoo are well-structured, but there are a few points to optimize for performance and stability:

Surfactant Concentration: Using 10% Sodium Methyl Cocoyl Taurate (90% Solid) provides 9% Active Surfactant Matter (ASM). When combined with 8% Cond-Foam™ (Liquid) (approx. 2.4% ASM), the total ASM is ~11.4%. This is excellent for a standard shampoo. For a "Pre-wash" applied to a dry scalp, this high concentration might feel slightly "tacky" during massage. You may consider slightly increasing the water content or using the Glutamate variants for better spreadability on dry hair.
Piroctone Olamine (1.0%): This is the maximum recommended dosage for rinse-off products. It is highly effective but must be completely solubilized to prevent crystallization. While Ethanol works, using Isopentyldiol or Propanediol is often preferred for scalp health to avoid the drying effect of high alcohol content.
pH Management: Gluconolactone is a Polyhydroxy Acid (PHA) that slowly hydrolyzes into gluconic acid, which will lower the pH over time. You must monitor the pH of the final formula over 2-4 weeks. Target a pH of 5.0–5.5 for optimal scalp health and Piroctone Olamine stability.
Viscosity: Since you desire a low-viscosity "liquid" system for the pre-wash, the Taurate and Glutamate surfactants are ideal as they do not thicken as easily as traditional sulfates, maintaining a "water-like" flow for easy scalp application.

2. Surfactant Variants (Replacing 10% Sodium Methyl Cocoyl Taurate)

To maintain similar cleansing power while adjusting for the specific characteristics of each surfactant, use the following replacement levels:

Variant 1: Gluta-Clean™ (Disodium Cocoyl Glutamate)

Replacement Level: 25.0% – 30.0% (Note: This is a liquid surfactant, so reduce the Water/Aqua in Phase A accordingly).
Characteristics: Extremely mild, anionic, and produces a fine, creamy foam. It is excellent for "high tolerability" and "minimal drying."
Tip: It performs best at pH 5.0–6.0. It will significantly lower the viscosity, making it perfect for your liquid pre-wash.

Variant 2: AminoWash™ (Sodium Lauroyl Glutamate, Fine)

Replacement Level: 9.0% – 10.0% (Powder form).
Characteristics: Similar to the Taurate but even milder. It leaves a very soft, hydrated after-feel on the scalp, making it the best choice for the Bond Repair Shampoo.
Tip: Like the Taurate, this requires heating (approx. 60-70°C) in water to dissolve completely.

Variant 3: Decyl Glucoside

Replacement Level: 15.0% – 18.0% (Liquid form).
Characteristics: A non-ionic surfactant with very high foaming power and excellent "flash foam" on dry hair.
Tip: Decyl Glucoside has a high natural pH (~11-12). You will need more Gluconolactone or Citric Acid to bring the final formula pH down to 5.5. It can be slightly more drying than Glutamates, so it is best suited for the Pre-wash for thorough cleansing.

3. Preservation & Self-Preserving Status

Are they self-preserving?

No. While Decyl Glucoside has a high pH that inhibits microbial growth in its concentrated form, and Gluta-Clean™ / Cond-Foam™ are stable, they are not self-preserving once diluted in your water-based formula (which contains ~70-80% water).
Furthermore, ingredients like Panthenol, Sodium PCA, and Niacinamide are excellent "food" for bacteria and mold.

Recommendation:
You must add a broad-spectrum preservative system. For these mild, amino-acid-based systems, we recommend:

Phenoxyethanol SA (Phenoxyethanol, Ethylhexylglycerin) at 1.0%.
Alternatively, Mild Preservative Eco (Benzyl Alcohol, Salicylic Acid, Glycerin, Sorbic Acid) at 1.0% if you prefer a "natural-compliant" system (ensure pH is below 5.5).

Summary Table for Adjustments

Feature	Taurate (Base)	Gluta-Clean™	AminoWash™	Decyl Glucoside
Foam Type	Dense/Rich	Fine/Creamy	Soft/Silk	Large/Bubbly
Mildness	High	Very High	Very High	Moderate
Viscosity	Medium-Low	Very Low	Low	Low
Best For	All-round	Pre-wash (Mild)	Bond Repair	Pre-wash (Deep Clean)

Mixing Tip: When using Cond-Foam™ (Sodium Lauroyl Sarcosinate), always add it last and stir slowly to minimize air entrapment, as it is a very high-foaming agent.