Pulsatile Release of Insulin from Layer‐by‐Layer Assembled Microgel Thin Films

We describe studies concerning the construction and characterization of insulin‐impregnated poly(N‐isopropylacrylamide‐co‐acrylic acid) microgel thin films prepared by Layer‐by‐Layer (LbL) polyelectrolyte assembly. These films can be built up in a highly uniform fashion and display linear buildup dependence even up to 30 layers. Thermoresponsivity of these drug loaded films can be utilized to obtain extended pulsatile release of insulin over many cycles. Continuous thermal pulsing allows solubilization of the embedded peptide and subsequent diffusion through the film layers. The magnitude of release can be tuned based on film thickness. This type of microgel thin film construct proves to be extremely robust and can potentially pulse out constant bursts of peptide for more than one month at a time.