Evaluation of blood interactions with a drug loaded protein matrix
Independent thesis Advanced level (degree of Master (One Year)), 30 credits / 45 HE creditsStudent thesis
Many things might happen in the body when a titanium implant is inserted into bone. Examples are activation of the immune system and imbalance between bone formation and bone resorption, which might lead to damaged bone around the implant and at worse, loosening of the implant.
Bisphosphonates, BP’s, is a class of drugs that is able to decrease the osteoclast (bone resorption cell) activity and thereby strengthen the bone. FibMat2.0 is a fibrinogen matrix and consists of a thin protein layer which can be applied on an implant and act as a local drug delivery system.
The work in this thesis was divided into two parts where aim of the first part was to study FibMat2.0 with integrated BP’s, and their effect in the presence of blood. The aim for the second part was to determine whether it was possible to incorporate antithrombotic drugs into the fibrinogen matrix. No detection method for the amount of drugs incorporated into the fibrinogen matrix was used but the fact that the drugs gave effect was verifying that it is possible to integrate other drugs than BP’s into FibMat2.0. Methods that have been used in the experiments in presence of blood are imaging of coagulation, fluorescence microscopy and cone-and-plate.
For the first part, the results showed that surfaces incubated with fibrinogen and fibrinogen with integrated BP’s act alike in regard to coagulation and platelet adhesion. Compared to titanium, which is known to be a biocompatible material, the surfaces with fibrinogen and fibrinogen with BP’s behave similar in regard to platelet adhesion. When it comes to coagulation, the surfaces coated with fibrinogen with or without an addition of BP’s have shown a longer coagulation time compared to the clean titanium surface.
For the second part, some conclusions have been drawn according to the results. Heparin and hirudin have shown anticoagulant effects when integrated in the matrix. The platelet inhibitor cangrelor seemed to have better effect when added in blood and incubated compared to incubation with the platelet inhibitor on the surface before incubation in blood. Finally, when combining heparin and cangrelor, very clear differences in regard to formation of fibrin network could be seen. It seems promising to be able to load different kind of drugs in FibMat2.0.
Place, publisher, year, edition, pages
2011. , 61 p.
titanium, implant, bisphosphonates, coagulation, platelet adhesion
IdentifiersURN: urn:nbn:se:liu:diva-68306ISRN: LITH-IFM-A-EX-11/2458-SEOAI: oai:DiVA.org:liu-68306DiVA: diva2:417791
UppsokPhysics, Chemistry, Mathematics
Aronsson, Henrik, M.Sc.Faxälv, Lars, Ph.D.
Tengvall, Pentti, Prof.