Liposomes are small, spherical vesicles made of a phospholipid bilayer. They have been widely studied as potential carriers for delivering drugs and other active agents into the skin. However, a new study published in the journal _Nature Communications_ has shown that liposomes cannot actually function as carriers transporting active agents into the skin.

The study, conducted by researchers at the University of California, San Francisco, used a variety of techniques to investigate the interaction of liposomes with the skin. They found that liposomes are unable to penetrate the skin's outermost layer, the stratum corneum. This is because the stratum corneum is made up of tightly packed cells that are impermeable to most molecules.

The researchers also found that liposomes are rapidly broken down by enzymes in the skin. This means that even if liposomes were able to penetrate the stratum corneum, they would not be able to deliver their active agents to the skin's deeper layers.

The findings of this study have important implications for the development of new drug delivery systems. Liposomes have been widely used in preclinical studies, but they have not been as successful in clinical trials. This is likely due to the fact that liposomes cannot actually function as carriers transporting active agents into the skin.

The researchers who conducted this study suggest that other drug delivery systems, such as nanoparticles or micelles, may be more effective at delivering active agents into the skin. These systems are smaller than liposomes and are able to penetrate the stratum corneum more easily.

The findings of this study represent a significant advance in our understanding of skin biology and drug delivery. They have the potential to improve the development of new drugs and treatments for skin conditions.