Active scaffolds for on-demand drug and cell delivery

TLDR

Porous biomaterials are widely used as tissue engineering scaffolds, but their drug release is limited to passive diffusion, degradation, and cell migration, preventing dynamic external control. This work introduces an active porous scaffold that can be remotely regulated by a magnetic field to deliver biological agents on demand. The scaffold is a macroporous ferrogel that undergoes >70 % deformation and volume change under a moderate magnetic field, triggering release of drugs, plasmid DNA, chemokines, and cells. The magnetic actuation produces large deformation, enabling enhanced release of various drugs and cells from the scaffold.

Abstract

Porous biomaterials have been widely used as scaffolds in tissue engineering and cell-based therapies. The release of biological agents from conventional porous scaffolds is typically governed by molecular diffusion, material degradation, and cell migration, which do not allow for dynamic external regulation. We present a new active porous scaffold that can be remotely controlled by a magnetic field to deliver various biological agents on demand. The active porous scaffold, in the form of a macroporous ferrogel, gives a large deformation and volume change of over 70% under a moderate magnetic field. The deformation and volume variation allows a new mechanism to trigger and enhance the release of various drugs including mitoxantrone, plasmid DNA, and a chemokine from the scaffold. The porous scaffold can also act as a depot of various cells, whose release can be controlled by external magnetic fields.