Delivery of active collagenase to skin using a lorentz-force actuated needle-free injector

The development of new therapeutics and the desire to reduce the frequency of needle stick injuries, overcome the improper reuse of needles, improve compliance, and reduce the prohibitive cost of disposal have fueled resurgent efforts to develop alternative drug delivery methods. This report discusses the use of a controllable Lorentz-force actuated needle-free injector to deliver a blend of bacterial collagenases to the skin. Drug ejected/injected using a preprogrammed pressure vs time profile through a 100 or 200 microm orifice showed activity comparable to that observed following ejection/injection using a conventional syringe as determined by a solution based fluorescence assay and zymography. In a live animal trial, necrosis, hair loss, and minimal bruising were observed at drug injected sites regardless of the delivery mode as were changes in tissue morphology.