Superhydrophobic Gated Polyorganosilanes/Halloysite Nanocontainers for Sustained Drug Release

Abstract

Inspired by the water repellency of the lotus leaf, superhydrophobic gated nanocontainers are fabricated by using halloysite nanotubes (HNTs) as the nanocontainers and polyorganosilanes (POS) as the molecular gates for sustained release of diclofenac sodium (DS). The nanocontainers are prepared by loading DS into the lumen of HNTs, and then modified by co‐condensation of hexadecyltriethoxylsilane and tetraethoxysilane. The nanocontainers are characterized with transmission electron microscopy, energy dispersive X‐ray analysis and FTIR, etc. The wetting behaviors of the nanocontainers and release behaviors of DS are also studied. DS molecules are loaded in the lumen of HNTs and POS is covalently bonded on the surface of HNTs‐DS. Wettability of the nanocontainers is controllable simply by the POS content. The nanocontainers show excellent superhydrophobicity with a water contact angle of 156.9° and a water shedding angle of 3°. The release of DS molecules is controlled by a new way, the air cushion between the superhydrophobic nanocontainers and the phosphate buffer solution (PBS). The DS molecules could only release from the limited place where the nanocontainers contact with PBS when the PBS is in the Cassie‐Baxter state on the surface of the nanocontainers.