(a) Whole blood platelet count, (b) platelet adhesion to collagen, (c) surface‐bound P‐selectin expression, and (d) thromboxane B2 release in plasma after in vitro incubation under pulsatile flow with physiological wall shear stress conditions with human whole blood at 37°C for various incubation times using empty loops (Empty) as negative reference, low‐density polyethylene (LDPE) as low reference, and polydimethylsiloxane (PDMS) as high reference. *p < 0.05 compared with the baseline (0 min), using a paired samples t test. **p < 0.05 between indicated references, using an independent samples t test.

(a) Whole blood platelet count, (b) platelet adhesion to collagen, (c) surface‐bound P‐selectin expression, and (d) thromboxane B2 release in plasma after in vitro incubation under pulsatile flow with physiological wall shear stress conditions with human whole blood at 37°C for various incubation times using empty loops (Empty) as negative reference, low‐density polyethylene (LDPE) as low reference, and polydimethylsiloxane (PDMS) as high reference. *p < 0.05 compared with the baseline (0 min), using a paired samples t test. **p < 0.05 between indicated references, using an independent samples t test.

Source publication
Article
Full-text available
During hemocompatibility testing, activation products may reach plateau values which can result in less distinction between hemocompatible and hemo-incompatible materials. Of concern is an underestimation of the blood activation caused by the biomaterial of interest, which may result in a false assessment of hemocompatibility. To elucidate the opti...

Citations

... In the case of blood-material tests, it was decided that we would perform an hour-long contact of the material with blood based on literature reports [52,53]. Tubulin is important for platelet mobilization, reshaping, and formation of pseudopod [54]. ...
... For dynamic testing, the samples were cylinders with an internal diameter of 5 mm and a length of 40 mm. Each sample was contacted with 5 mL of whole blood circulating in a flow system with a 20 mL/min flow for 1 h as recommended by the other authors [52]. After this time, the materials were rinsed with 0.9% NaCl and further analyzed. ...
Article
Full-text available
This study describes a method for the modification of polyurethane small-diameter (5 mm) vascular prostheses obtained with the phase inversion method. The modification process involves two steps: the introduction of a linker (acrylic acid) and a peptide (REDV and YIGSR). FTIR and XPS analysis confirmed the process of chemical modification. The obtained prostheses had a porosity of approx. 60%, Young’s Modulus in the range of 9–11 MPa, and a water contact angle around 40°. Endothelial (EC) and smooth muscle (SMC) cell co-culture showed that the surfaces modified with peptides increase the adhesion of ECs. At the same time, SMCs adhesion was low both on unmodified and peptide-modified surfaces. Analysis of blood-materials interaction showed high hemocompatibility of obtained materials. The whole blood clotting time assay showed differences in the amount of free hemoglobin present in blood contacted with different materials. It can be concluded that the peptide coating increased the hemocompatibility of the surface by increasing ECs adhesion and, at the same time, decreasing platelet adhesion. When comparing both types of peptide coatings, more promising results were obtained for the surfaces coated with the YISGR than REDV-coated prostheses.
... Therefore, determination of osseointegration process in vivo using large animal model is necessary to introduce novel biomaterial into the clinical use. Although ex vivo models were successfully used in the engineering of biomaterials and regenerative medicine to determine blood-implant interactions (hemocompatibility) [27][28][29], cartilage repair upon scaffold implantation [30][31][32], bone repair (without biomaterial -only within the defect) [33], or wound healing process [34][35][36][37], to our best knowledge this is the first report presenting ex vivo determination of biomaterial osseointegration using human bone explant. In this research it was demonstrated by SEM and CLSM imaging that bone explants may be kept alive for long period of time (at least approx. ...
Article
Permanent orthopedic/dental implants should reveal good osseointegration, which is defined as an ability of the biomaterial to form a direct connection with the surrounding host bone tissue after its implantation into the living organism. Currently, biomaterial osseointegration is confirmed exclusively with the use of in vivo animal tests. This study presents for the first time ex vivo determination of osseointegration process using human trabecular bone explant that was drilled and filled with the chitosan/curdlan/hydroxyapatite biomaterial, followed by its long-term culture under in vitro conditions. Within this study, it was clearly proved that tested biomaterial allows for the formation of the connection with bone explant since osteoblasts, having ability to produce bone extracellular matrix (type I collagen, fibronectin), were detected at a bone-implant interface by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Importantly, in this research it was demonstrated by Live/Dead staining and CLSM imaging that human bone explants may stay alive for a long period of time (at least approx. 50 days) during their culture under in vitro conditions. Therefore, ex vivo bone explant, which is a heterogeneous tissue containing many different cell types, may serve as an excellent model to test biomaterial osseointegration during comparative and preliminary studies, reducing animal tests which is compatible with the principles of ‘3Rs’, aiming to Replace, Reduce and Refine the use of animals wherever possible.
... Under blood flow exposure the circulating proteins and platelets are adsorbed on the biomaterial's surface, which cause thrombus formation. The aim of hemocompatibility is to prevent this protein and platelet adsorption on the surface [2][3][4]. Endothelial cells (ECs) make the inner layer of blood vessels and regulate the hemostasis. ECs are adhered on a nanostructured extracellular matrix (ECM) layer known as basement membrane, consisting of nanofibers of collagen, laminin, nidogen, and perlecan, to form an integrated monolayer with tight junctions between adjacent cells [5][6][7]. ...
Chapter
The extracellular matrix as a microenvironment and supportive structure of the cells has a nanostructured architecture. Therefore, producing the biomaterials with nanostructure morphology improve the biocompatibility and hemocompatibility of these products. This book chapter describes the importance of cardiovascular biomaterials and the hemocompatibility issue of these devices. Then, the nanoscaled biomaterials as the biomimetic microenvironment to improve the hemocompatibility and tissue healing are introduced. Finally, nanostructured surfaces and nanoparticles which can be employed in cardiovascular diseases are comprehensively discussed.
... Incubation times are usually recommended of approximately 60 min. However, at most 4 h of incubation are possible due to blood instability [46,47,56,57]. ...
Article
Hemocompatibility testing is essential for the safe use of medical devices that come into contact with blood. There are various evaluation methodologies. In vivo, ex vivo and in vitro systems can be used and different categories can be evaluated in different ways. This review deals with in vitro hemocompatibility testing mainly on the basis of ISO standard 10993-4 recommendations and possibly new research results. This is a summary of all tested categories, i.e. coagulation, hemolysis, hematology and activation of leukocytes and platelets and the complement system. The main principle of evaluation and the possibilities of testing using various methodologies are always described. In the next part, variants of the method of blood incubation with the tested medical device from the static system to the circulation are described. Circulation can be provided, for example, by means of the Chandler Loop or parallel-plate chambers.
Article
Background: To determine suitable alternatives to human blood for in vitro dynamic thrombogenicity testing of biomaterials, four different animal blood sources (ovine, bovine, and porcine blood from live donors, and abattoir porcine blood) were compared to fresh human blood. Methods: To account for blood coagulability differences between individual donors and species, each blood pool was heparinized to a donor-specific concentration immediately before testing in a dynamic flow loop system. The target heparin level was established using a static thrombosis pre-test. For dynamic testing, whole blood was recirculated at room temperature for 1 hr at 200 mL/min through a flow loop containing a single test material. Four materials with varying thrombotic potentials were investigated: latex (positive control), polytetrafluoroethylene (PTFE) (negative control), silicone (intermediate thrombotic potential), and high-density polyethylene (HDPE) (historically thromboresistant). Thrombus weight and surface area coverage on the test materials were quantified, along with platelet count reduction in the blood. Results: While donor-specific heparin levels varied substantially from 0.6 U/ml to 7.0 U/mL among the different blood sources, each source was able to differentiate between the thrombogenic latex and the thromboresistant PTFE and HDPE materials (P< 0.05). However, only donor ovine and bovine blood were sensitive enough to differentiate an increased response for the intermediate thrombotic silicone material compared to PTFE and HDPE. Conclusions: These results demonstrated that multiple animal blood sources (particularly donor ovine and bovine blood) may be suitable alternatives to fresh human blood for dynamic thrombogenicity testing when appropriate control materials and donor-specific anticoagulation levels are used.