Smart bacteria cellulose facial mask for sensing and recovering skin pH

The utilization of skin care products and cleansers is a prevalent method for maintaining facial skin health. However, excessive use of these products is an unnoticed factor that can result in serious skin problems. Currently, there are no products on the market to provide users with skin acclimatization and restoration services. Herein, we introduce a facial mask with a smart pH sensor to monitor and repair facial skin. Specifically, bacterial cellulose fragments were mechanically dispersed, co-mingled with carboxymethyl cellulose and hydroxypropyltrimethylammonium chloride chitosan, with anthocyanin added as a pH-indicating reagent. The composite mask was then prepared by hot air drying. This mask exhibited notable anti-hornification effect, robust water absorption, water retention, wet strength, and antibacterial and antioxidant properties, making it suitable for a high-end facial mass base material with an excellent pH sensitivity within the range of 2.0–12.0, which could be observed directly through colorimetry with the naked eye.