Patent ID: 8628536

Claim:
A system for delivering a biological material to a treatment site, the system comprising: a chamber for containing the biological material; and a delivery apparatus for transferring the biological material from the chamber to the treatment site, the delivery apparatus comprising: a housing; an outer plunger extending through the housing; an inner plunger, wherein the inner plunger slides within the outer plunger; and a pawl, wherein the pawl comprises a tooth portion and a tab portion, wherein the tab portion extends outside the housing beside the outer plunger; wherein the delivery apparatus comprises: a first configuration in which the tooth portion is biased toward the outer plunger, a second configuration in which the tab portion is urged toward alignment with the outer plunger to temporarily overcome the bias, a third configuration in which the tooth portion is biased toward the inner plunger, and a fourth configuration in which the tab portion is urged toward alignment with the inner plunger to temporarily overcome the bias.