Hybrid poly(allylamine hydrochloride)–graphene oxide microcapsules: preparation, characterization and application in textiles with controlled release behavior†
Permeable microcapsules are suitable forming blocks for functional materials based on controlled release. This study reports the design of a stimuli-responsive fabric coated with a type of hybrid microcapsules prepared via a layer-by-layer (LBL) approach. The resulted fabric can be used as a healthy care material. The functional microcapsules comprise polyelectrolytes poly(allylamine hydrochloride) (PAH) and graphene oxide (GO). The self-assembly of these oppositely charged surrounding components generated a hollow space to load functional molecules such as dyes, labels and drugs via a responsive trigger. The polyelectrolyte PAH ensured a robust structure and pH sensibility. GO sheets provided near-infrared (NIR) laser-induced release through photothermal effects. These hybrid microcapsules (PAH/GO)nPAH can then be used to load Atractylodes, a traditional Chinese herb, and then adhere to cotton fabrics to develop functional textiles. The encapsulated Atractylodes can then be released from the (PAH/GO)nPAH-coated cotton fabric. During the subsequent period of the entire process, the release rate was significantly accelerated by NIR irradiation. After washing 20–30 times, microcapsules were coated on cotton fibers. Using this technique, functional textiles for controlled release by external stimulation coupled with other synergetic effects could be obtained. Note that (PAH/GO)nPAH microcapsules can provide sustained drug release in simulated sweat and control the release rate through NIR irradiation, which shows its potential as an external skin drug delivery system.