Sodium arachidate

// Evidence: Buffering systems resist pH changes through weak acid-conjugate base pairs (citric acid/sodium citrate, lactic acid/sodium lactate, phosphate salts) that operate within specific pH ranges based on their pKa values. The mechanism follows the Henderson-Hasselbalch equation, with buffer components neutralizing added H⁺ or OH⁻ ions. Proper buffering prevents pH drift and maintains efficacy.

// Evidence: Emulsion stabilizers maintain dispersion of immiscible phases by preventing droplet coalescence through interfacial film formation, electrostatic repulsion, steric stabilization, viscosity enhancement, or network formation. Stabilizers include polymers (carbomers, xanthan gum), proteins, and modified celluloses. The combination of primary emulsifiers with secondary stabilizers creates robust lamellar liquid crystalline structures.

// Evidence: Cleansing surfactants specifically formulated for removing sebum, dirt, and impurities. Primarily anionic (sodium laureth sulfate, sodium cocoyl isethionate) and amphoteric surfactants (betaines). Mechanism involves reducing surface tension enabling water to wet oily surfaces, solubilizing lipophilic materials in micelles, and emulsifying oils for rinse-off. Cleansing efficacy balanced with mildness by surfactant selection, concentration, and pH optimization. Must avoid excessive lipid removal that compromises barrier function.

// Evidence: Emulsifying surfactants enable creation of stable oil-in-water or water-in-oil emulsions by positioning at oil-water interface, reducing interfacial tension. HLB (hydrophilic-lipophilic balance) determines emulsion type: HLB 3-6 for W/O, HLB 8-18 for O/W emulsions. Examples include polysorbate 80, ceteareth-20, glyceryl stearate. Mechanism involves forming interfacial film preventing droplet coalescence. Often used in combinations with co-emulsifiers (fatty alcohols) creating lamellar structures for enhanced stability.