Hydroxy acid $pK_a$

The modernization of cosmetic chemistry has effectively phased out aggressive, mechanical physical scrubs in favor of chemical desquamation. Hydroxy acids—Alpha-Hydroxy Acids (AHAs), Beta-Hydroxy Acids (BHAs), and Poly-Hydroxy Acids (PHAs)—have become foundational pillars in clinical skincare, celebrated for their ability to treat hyperpigmentation, accelerate cellular turnover, and clear acneic congestion. However, the rapid democratization of high-concentration…