Preparation of isometric Liesegang patterns and application in multi-pulsed drug release system

Abstract

AbstractIn this paper, the feasibility was demonstrated to turn Liesegang patterned gelatin hydrogel into the multi-pulsed drug release system. Calcium hydrogen phosphate (CaHPO4) crystals were selected as the Liesegang rings (LRs) materials. The structure of CaHPO4/gelatin was well tailored by adding the sodium dodecyl benzene sulfonate (SDBS) micelles or SDBS/cholesterol microcapsules. As a result, the completely isometric CaHPO4/gelatin LRs were prepared. The enzymolysis of gelatin with isometric LRs and cholesterol/SDBS microcapsules was carried out by using typsin. A stepwise kinetic curve of enzymolysis was obtained due to the obstacles of CaHPO4 rings. This result indicated that CaHPO4/gelatin LRs were potentially a versatile platform for the multi-pulsed release of various drugs.\n HighlightsLiesegang pattern of CaHPO4 in gelatin is modified by adding sodium dodecyl benzene sulfate (SDBS) surfactant.Additional to the increase of ring number with the increase of SDBS concentration, the isometric (equal spacing) Liesegang pattern is prepared with 16 mmol/L SDBS.It is proved that the isometric Liesegang pattern is a potential device in the application of multi-pulse drug release.