Skin moisture tester

Measure the moisturizing effect of cosmetics,

The measurement of hydration in the stratum corneum refers to the ability of keratin or its degradation products in the outer layer of the skin to bind with water. in
Hydration can increase the moisture content of the stratum corneum of the skin, with a normal moisture content of 10% -20%,
The moisture content of the stratum corneum is influenced by various internal and external factors. Under normal physiological conditions, the moisture content of the stratum corneum varies not only depending on the testing site, but also closely related to gender, age, genetics, nutrition, and living environment (such as air humidity and temperature).

Gender and Age

Normally, the moisture content of infants' stratum corneum is higher than that of adults. The decrease in moisture content in the stratum corneum of elderly people is related to a reduction in their natural moisturizing factors. Although most studies have shown no significant difference in the moisture content of the stratum corneum between men and women, systemic or local use of estrogen can significantly increase the moisture content of the stratum corneum in postmenopausal women [1].

aquaporin

There are a total of 13 aquaporins (AQP 0-12) on the cell membrane of mammals, among which AQP3 has permeability to both water and glycerol. Animals lacking AQP3 have reduced water content in their stratum corneum; Stimulating the synthesis of AQP3 in the epidermis can increase the moisture content of the stratum corneum