Retraction Note: Fabrication of a microfluidic device for studying the in situ drug-loading/release behavior of graphene oxide-encapsulated hydrogel beads

Background Controlled drug delivery system is highly important for not only prolonged the efficacy of drug but also cellular development for tissue engineering. A number of biopolymer composites and nanostructured carriers behave been used for the controlled drug delivery of therapeutics. Recently, in vitro microfluidic devices that mimic the human body have been developed for drug-delivery applications.