Nano-container assembled thin films with time-programmed release of hydrophobic dyes

We introduce an all nano-container assembled multilayer thin films for controlling the release of hydrophobic functional materials. Two complementary charged block copolymer micelles were used as a nano-container for layer-by-layer assembly of thin films. Block copolymer micelles were composed of positively charged hairy polystyrene-block-poly(4-vinylpyridine) and negatively charged hairy (long corona region relative to the hydrophobic core part) or crew-cut (huge hydrophobic core chains, compared with the hydrophilic corona region) polystyrene-block-poly(acrylic acid) micelles. Two different fluorescent dye-incorporated block copolymer micelles multilayer films deconstructed when rehydrated in physiological condition, phosphate buffer saline solutions, releasing block copolymer micelles as a hydrophobic material carrier, suggesting that the detachment behavior of block copolymer micelles integrated into the multilayer films differs according to layer-by-layer assembled block copolymer micelle combinations. These results indicate the suitability of thin films for applications including the controlled release of hydrophobic materials. Atomic force microscope analysis suggested the successful preparation of block copolymer micelles. Film growth and release of fluorescence dyes were monitored by UV-Vis spectra.