Protein Enhanced Bone Recovery By Amanda Walker Working

Protein Enhanced Bone Recovery By Amanda Walker Working with Ashley Aston Weiner Mentored by Prasad Shastri

Analysis- Primary Objective l Main goal- to optimize protein release from a bone repair biopolymer l Goal components l minimize burst effect by optimizing porosity l Obtain a linear release of protein over 3 to 4 weeks (life span of polymer) l Factors to vary l Porogen material l Porogen concentration l Size of gelatin microspheres http: //www. oplin. org/point/ http: //www. sciencedirect. com/science? _ob=Article. URL&_udi=B 6 T 3 D-438 BNXR 1&_cover. Date=06%2 F 15%2 F 2001&_alid=368044133&_rdoc=1&_fmt=&_ orig=search&_qd=1&_cdi=4944&_sort=d&view=c&_acct=C 000006878&_version=1&_url. Version=0&_u serid=86629&md 5=d 5 be 4 d 79321979 caf 317181 be 7 c 98482

Analysis- Problem Statement The data we have for the porosity effects are not sufficient. l Porogens mixed into polymer control protein release. l Previous protein release studies done from linear polymers. l http: //members. tripod. com/sunfh/pol 6. gif

Analysis- Polymer explanation How does it work? l Polyanhydride degrades over the course of a month l Porogens quickly dissolve creating holes l l l http: //www. synergizedsolutions. com/simpsons/pictures/bart/scientist. gif http: //www. nrc-cnrc. gc. ca/education/images/science/photos/victoria_02. jpg Exposes proteins Proteins are growth factors Bone grows in as material degrades

Market Analysis l The market l Broken bones l l Bone disease l l 3 femur fractures per 10, 000 population annually for young and old people 50% of women 50+ have fractures related to osteoporosis Spinal fusion l 290, 000 surgeries in 2003 http: //www. drrathresearch. org/clinical_studies/condition_bonefracture_print. html http: //www. paralumun. com/osteoporosisstats. htm http: //www. aaos. org/wordhtml/research/stats/spinefusion_recent. htm

Market Analysis l Competition l ETEX corporation l l l Nova. Bone l l Endothermic curing takes 15 -20 minutes No proteins Molds to shape of injury, but not immediately Benefits over competition l l l Less invasive More comfortable Custom fit Instant curing Enhancement by growth factors Crosslinking=material strength http: //www. etexcorp. com/etex/content/products/index. shtml http: //www. novabone. com/prod 03. htm

Analysis- Background l Precedent- BCNU release study l l l Wafer placed in hole after glioblastoma removal Release of BCNU kills leftover cancer cells Improves lifespan This device is currently being used in medicine. l Several other papers were researched. l http: //www. neuropat. dote. hu/jpeg/tumor/3 gliobl 1. jpg

Analysis- Material Components l Monomers l l Salt Gelatin + MCPH + MSA Photoinitiator/ Blue light Protein/sugar l l MSA MCPH Porogen l l Porogens and Proteins HRP as test protein Crosslinking initiator Crosslinked polymer

Analysis- Polymerization Initiator= camphorquinone l Forms free radicals when exposed to blue light l l l http: //www. bonartmed. com/upload/product/1/1096423878014_0. JPG http: //www 3. interscience. wiley. com/cgibin/abstract/109792870/ABSTRACT? CRETRY=1&SRETRY=0 By hydrogen atom extraction Radicals initiate crosslinking

Synthesis of Samples- Block Diagram Mix protein and sugar Add initiator Coomassie assay Granulate protein Mix monomers, protein, and porogen Make and/or quantify porogen Mold and expose

Hypothesis- Performance Metrics How will improvement be measured? l Polymerized samples will be degraded in 37 degree PBS. l PBS will be changed daily. l The old PBS will be analyzed using a protein quantification assay. l This will determine how much protein was released over the last time period.

Analysis- Performance Criteria Constraints l Release=3 -4 weeks l Avoid burst effect l Limitations l Time- 4 months l Money- no real constraints l Exclusions- some porogens l FITC-dextran, for example l BSA as a protein- too much background in negative controls l Burst Effect

Validation- Current Status l Accomplished: l l l Protein uniformity verification Protein quantification Protein and porogen granulation Made the cylindrical samples for the first porogen (Na. Cl) Current work l Had to change the protein used from BSA to horseradish peroxidase (HRP) l l l Due to this we are using a different assay to quantify release in the degradation studies The Coomassie assay was still used for protein uniformity verification Degradation study of the Na. Cl porogen samples l Slightly delayed (about 2 weeks) due to the necessity of changing the protein

Process Diagram for Protein Uniformity Assay