Thien-ChuongN.Phung from the University of Memphis is investigating the attachment of rat sciatic nerve segments to silica-based aerogel substrates for implant applications. Aerogels are very lightweight solids with high porosity that can be designed to control pore size. A silica-based aerogel implant is being developed to precisely guide and connect multiple severed nerves simultaneously. Existing nerve repair techniques have limitations. This study focuses on attaching rat sciatic nerve segments to aerogel substrates using biological and non-biological adhesives. Tensile strength tests were performed under varying conditions. In some cases, the attachment strength was greater than expected and withstood high loads past the point of nerve rupture.

1. INVESTIGATION OF RATSCIATIC NERVEATTACHMENTTO SILICA-BASED
AEROGELS FOR IMPLANTAPPLICATIONS
Thien-ChuongN.Phung(Dr.FirouzehSabri),Departmentof Biomedical Engineering&Physics,University
of Memphis,Tennessee
Aerogelsare arelativelynew classof material withaunique setof properties.Theyare the most
lightweightsolidknown(~0.1g/cm3) andcan be designedwithhighporosity(~99% air) as well as
control overthe size of the pores.A silica-basedpolyureacross-linkedaerogel device iscurrentlyunder
developmenttoserve asan implantforperipheral nerverepairreferredtoasa neuronal printedcircuit
board (NPCB).Thisimplantwill be capable of the precise guidance andconnectionof distal andproximal
endsof multiple nerves(n-D) simultaneously.Existingnerve repairtechnologyislimitedtotube-shaped
implantsandscaffoldsthatsufferfromcomplicationssuchasnerve saggingandimplantswellingafter
exposure toa wetenvironment.Thesetypically contribute tonerve pinchingandpatientcomplaints.
Approvedsuturingtechniquesforattachmentof suchimplantshave shownalarge numberof surgeries
failingdue tohemorrhaginganddamage tothe nerves.The NPCBwill be attachedtothe nervous
systembymeanof biological andnon-biological adhesives.Inthisworkourfocusisto investigate the
attachmentof sciaticnerve segmentsremovedfromcadaverSprague Dawleyratstoaerogel substrates
by meansof biological andnon-biological adhesives.Tensilestrengthtestswere performedonmultiple
sampleswithandwithoutthe adhesioncomponentsundervaryingenvironmental conditions.Insome
cases,the attachmentstrengthof nerve segmenttothe aerogel substrate wasgreaterthanexpected
and withstoodhighloadspastthe pointof nerve rupture.Furtherstudiesof attachmentwillbe
performedincludingassessingadhesionstrengthundermultiple-directionmovement.The same
experimentswereconductedinvivoandthe resultswill be reported.