Dendritic growth of protein gel in the course of sweat pore plugging by aluminium salts under physiological conditions.

Are aluminium ions unavoidable in antiperspirants? To answer this question, we present confocal microscopy images of dendritic plugs appearing in sweat flowing across a microfluidic channel in the presence of aluminium salts. By comparing with numerical simulations, we identify the mechanisms forming this structured protein gel inside the pore.

Real time observation of the interaction between aluminium salts and sweat under microfluidic conditions.

Aluminium salts such as aluminium chlorohydrate (ACH) are the active ingredients of antiperspirant products. Their mechanism of action involves a temporary and superficial plugging of eccrine sweat pores at the skin surface. We developed a microfluidic system that allows the real time observation of the interactions between sweat and ACH in conditions mimicking physiological sweat flow and pore dimensions.