pH-responsive release of TiO2 nanotube arrays/mesoporous silica composite based on tannic acid-Fe(III) complex coating

In this work, TiO2 nanotube arrays/mesoporous silica composite coated with tannic acid-Fe(III) complex was prepared with a simple drip coating method. The coating significantly inhibited the burst release in the early stage of drug release. The coordination conditions of the material were different under different pH values. This resulted in different stabilities of the coating, thus controlling the release of Loxoprofen Sodium (LS) at different pH values to construct a pH-responsive drug delivery system. To demonstrate this principle, the authors loaded LS into the samples and triggered pH-induced release. The excellent biological activity of the samples was confirmed in vitro by the significant growth and differentiation of MC3T3-E1 osteoblastic cells. The data has shown that the samples had achieved intelligent control of drug release and would have a wide range of applications.