A. Huth, C. Flanagan, A. Rieves, J. Sass Client: W. John Kao, Ph.D 1,2 Advisor: Naomi Chesler, Ph.D 2 1 School of Pharmacy, 2 Department of Biomedical Engineering A. Huth, C. Flanagan, A. Rieves, J. Sass Client: W. John Kao, Ph.D 1,2 Advisor: Naomi Chesler, Ph.D 2 1 School of Pharmacy, 2 Department of Biomedical Engineering ReferencesReferences Future Work BackgroundBackground MotivationMotivation Final Design AbstractAbstract TestingTesting INTERPENETRATING NETWORKS FOR DELIVERY SYSTEMS Problem Statement Design Constraints Our goal is to create a novel delivery mechanism to reconstitute the components of an interpenetrating network (IPN). Interpenetrating networks that are composed of gelatin cross-linked with PEG da provide a promising solution to decrease healing time for large surface area wounds. However, the current reconstitution and administration methods of this product are clinically undesirable. Our final design of a modified syringe was selected based on the design constraints set forth by our client. This design enables the liquid and solid components of an IPN to be stored separately and offers a simple and ergonomic method for mixing and administration. Prototypes of this design were fabricated and tests were also performed to assess how well the prototype met the design constraints. Large surface area and chronic non-healing wounds are difficult to treat Bioactive wound dressings are becoming more prevalent in clinical settings Bioactive wound dressings increase healing time. Current delivery methods are clinically impractical What is an IPN? An IPN is effectively a bioactive dressing for large surface area wounds Benefits of IPNs Moist healing environment Conforms to irregular wounds Covers large surface areas Delivers drug cocktails Biocompatible Current Administration Technique Day 7 Day 3 Day 1 Ingredients/ drug(s) in multiple containers Mix 1 1 Cover 5 5 Heat Inject Syringe is use to administer solution 4 4 Cure in 30 sec to obtain a rubbery film 6 6 Sustained Release while the IPN biodegrades 7 7 Clean Components pegDA Gelatin Photoinitator Water Drawbacks of Current Administration Technique Heat Uneven administration Lengthy application process Multiple containers IPN Conventional Dressings Irregular Wound U-Mix Baby Bottle West Pharmaceuticals Services Needless Transfer Device Additional testing -Ergonomics -Reproducibility Streamlined manufacturing FDA approval Packaging -Syringe packaged in form fitting Styrofoam® insulation -Cardboard box surrounding insulation will provide UV protection Features One-way Valve -Embedded in plunger -Spring mechanism, normally closed -Prevents backlog of solution into upper compartment Seal -Creates barrier between upper chamber and the atmosphere -Creates pressurized chamber for sustained liquid release through atomizer Atomizer with luer-lock connection -Provides even spray -Covers variable surface areas Product should be designed for one-time use Custom fabrication should be avoided Liquid and powder IPN components must be isolated Integrity of chemicals must be maintained Mixing procedure and administration technique should be simple and ergonomic An even spray pattern should be produced UV protection should be incorporated into the design Cost Projection * Cost projections are based on production of approximately 1000 units. 1. Insert diluents vial use any side 2. Pull out the package3. Place powder vial on the table and insert. 4. Turn handle towards drug and remove cap 5. Connect the syringe filled with air and inject air into the drug. 6. Turn the system so the drug is on top and aspirate drug into the syringe. Prior Art Step by Step Procedure 1)Draw back plunger Decreases pressure in solid chamber Forces one-way valve open Moves liquid into syringe barrel 2)Shake syringe Mixes liquid and solid components 3)Depress plunger One-way valve prevents backflow Expels solution through atomizer 4) Cure IPN with UV-light Full Assembly Valve Exploded View Atomizer Attachment Surface area covered in in 2 by dispensing 5mL of liquid through atomizer tip from a distance of 1, 3, & 5 inches away. Error bars represent +/- SE 1 (n=5). Average barrel pressure as a function of plunger force. Values are based off of 5 second averages sampled at 10kHz using Harvard Apparatus pressure Transducer (Part # ). Source :U-Mix Baby Bottle pamphlet ©2007 Source :West Pharmaceuticals product information ©2007 UMIX. UMIX Travel Bottle Instructions. Product Brochure. Vowden, K. and P. Vowden. “Wound-Bed-Preparation.” World Wide Wounds Bradford Royal Infirmary. 29 April West Pharmaceutical Services. Instructions-Sheet Needleless Transfer Device. Product Brochure. Supplementary Research Preliminary research has been conducted to find a means to bypass the heating step in the administration technique -Cold H 2 0 soluble gelatin -Solvent other than H 2 0 Source : Vowden, K. & P. Vowden, 2002.