Nanopores in Biodegradable Silk/Magnetic Nanoparticle Membranes

© 2022 EPFL

© 2022 EPFL

Congratulations to Dr. Ya Wang, former PhD student at LMIS1, for her new publication entitled "Nanopore Generation in Biodegradable Silk/Magnetic Nanoparticle Membranes by an External Magnetic Field for Implantable Drug Delivery" in the journal "ACS Applied Materials and Interfaces"

Implantable devices for localized and controlled drug release are important, e.g., for therapies of cancer and chronic pain. However, most of the existing active implants are limited by the usage of nonbiodegradable materials; thus, surgery is needed to extract them after the treatment, which leads to secondary damage. Here, we show a fully biodegradable composite membrane made from silk fibroin and magnetic nanoparticles (MNPs). The membrane porosity can be remotely modified by an alternating magnetic field, which opens nanopores by local heating of MNPs in the composite allowing a liquid to diffuse through them. The stability of the silk membrane in water can be prolonged up to several months by increasing its β-sheet content through ethanol annealing. We present the following original findings. (a) Nanopores can be generated inside the silk/MNP composite membrane by exposing it to an external alternating magnetic field. (b) A longer exposure time results in more nanopore sites. (c) The controllable release of rhodamine B dye is achieved by tuning the period of exposure to the magnetic field. The obtained results demonstrate the suitability of the investigated silk/MNP composite membrane as a potential functional material for implantable drug delivery.

Dr. Ya Wang was a former member of LMIS1, where she obtained her PhD in 2020. She is now working in the framework of the Food Science and Technology Program at Beijing Normal University-Hong Kong Baptist University United International College.

For more details, please visit:


This project is financially supported by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (Project “MEMS 4.0”, ERC2016-ADG, Grant Agreement 742685), the China Scholarship Council (201306270060), the National Natural Science Foundation of China (61804023), and the Fundamental Research Funds for the Central Universities (ZYGX2019Z002).