Rheological blends for drug delivery. II. Prolongation of nerve blockade, biocompatibility, and in vitro–in vivo correlations

Rheological polymer blends of hyaluronic acid (HA) and hydroxypropylmethyl cellulose (HPMC) were evaluated as prolonged duration delivery vehicles for local anesthetics using a rat sciatic nerve blockade model. HA-HPMC blends extended the duration of sensory block approximately threefold compared to that achieved using a bupivacaine solution. Blending HA and HPMC facilitated the injection of higher polymer concentration delivery vehicles and …