Self-rupturing microcapsules

Self-rupturing microcapsules are prepared by layer-by-layer coating of degradable dextran-hydroxyethyl methacrylate microgels with the polyelectrolytes poly(allylamine hydrochloride) and sodium poly(styrene sulfonate). When the microgel core degrades, the swelling pressure increases and, at a critical value of the swelling pressure, the surrounding membrane suddenly ruptures (see Figure). This type of microcapsule could be very promising for pulsed drug delivery.