Percutaneous penetration enhancers can regulate the transdermal absorption of drugs. Generally speaking, it can be divided into two categories: chemical synthesis and natural sources. Natural percutaneous penetration enhancers have the advantages of safety and mildness. This review summarizes the mechanism and characteristics of three kinds of percutaneous penetration enhancers and their combined application in transdermal drug delivery systems. The three different types of percutaneous penetration enhancers are fatty acids, alkaloids and terpenes. It is expected to provide considerations for the application research of percutaneous penetration enhancers rich in traditional Chinese medicines in transdermal drug delivery systems.

As a new type of material with application prospect in drug delivery system, DNA origami nanostructures (DONs) have showed unparalleled abilities on nanoparticle drug delivery. However, the subcellular distribution of DONs after entering cells remained unclarified. Herein, we studied the phagocytic rate of U87 cells on fluorescent triangular DNA origami and Cy5 labelled Gold nanoparticles (Cy5-AuNPs) after 24 h. Atomic force microscope, confocal microscopy and immunofluorescence analysis (four organelles) were used to characterize their morphology. We found that DONs distributed in late endosome and lysosome. Meanwhile, gold nanoparticles enter the cells from early endosome to late endosome, and then exit the cells through exocytosis. The results provide us the novel insight for the design and optimization of DNA triangular origami nanostructures vehicles for drug delivery.

The appropriate delivery system is necessary for insoluble bioactive substances with poor water solubility, instability and low bioavaiability. The delivery system is key to improve its application characteristics. In terms of improving bioavailability of insoluble substances, emulsions have great advantages over other delivery systems. In this paper, the present researches on emulsion carrier systems of insoluble substances are reviewed including carotenoids, anthraquinones, diketone compounds, flavonoids, etc. At the same time, a summary on the development of insoluble substances food and drugs is presented, which is beneficial to the improvement of the research technology in this field.