Design and Development of a Dual-Chamber Syringe
By Professor Daniel Bar-Shalom (School of Pharmaceutical Sciences, University of Copenhagen)
How it works
1 – Plungers, assembly and filling
The front part of the inner plunger is mounted onto the outer plunger, defining a ”vial” into which the dissolved drug is filled. Then, the drug is freeze-dried around the rod.
2 – Syringe assembly and solvent filling
The rear part of the inner plunger joins the front part, sealing the drug under vacuum, and a lock immobilizes the inner plunger. The plunger assembly is inserted into the body of the syringe, the vehicle filled into the front chamber and the needle sealed.
3 – The end-user handling
The user removes the lock and moves the inner plunger in and out repeatedly, the perforated disk on the plunger facilitates dissolution. Then, the lock is returned and the needle unplugged.