Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Development of atomic layer deposition hemocompatible coatings for materials dedicated for the implants in the cardiovascular environment

Szawiraacz Karolina, Kurtyka Przemysław, Więcek-Chmielarz Justyna, Zając Zuzanna, Basiaga Marcin, Taratuta Anna, Ostrowski Roman, Major Roman

Engineering of Biomaterials

2024

vol. 27, no. 172

38--53

An atrial septal defect (ASD) is one of the most common congenital heart defects in children and the most frequent congenital defect found in adults. Currently, several types of kits are available for percutaneous closure of ASD. The design of these implants is based on the Nitinol alloy. Despite the good biocompatibility of Nitinol alloys, the use of these materials for long-term implantation is questionable due to the high nickel content and the risk of releasing nickel ions as a result of corrosion in the body’s environment. A way to improve the hemocompatibility of Nitinol alloys is to modify their surface. As part of this work, the conditions for the production of SiO2 surface layers using the atomic layer deposition (ALD) method and laser surface modification with three different laser cutting speeds were developed to improve biocompatibility. This allowed us for the comparison of different surface modifications (ALD and laser modification) in terms of their impact on cell-material interactions. The general analysis concerning biocompatibility confirmed the biological usability of the designed ALD deposited coatings. Surface nanostructuring had a positive effect on the natural biological layer formation. The analysis performed indicated the appropriate behaviour of the natural biological layer, known in the literature as pseudointima, in contact with blood. It was evident that platelet activation on the surface was reduced.

Biofunctionalization through the use of polyelectrolyte micelles and erythrocytes

Więcek-Chmielarz Justyna, Kajzer Wojciech, Chwiej Joanna, Wilk Aleksandra, Zając Zuzanna, Major Roman

Engineering of Biomaterials

2024

vol. 27, no. 172

54--61

Biological functionalization is a critical area of research aimed at enhancing the functionality and application of biomaterials in various biomedical fields. One of the key aspects of biofunctionalization involves the addition of growth factors, which can significantly improve the biocompatibility of materials. Enhanced biocompatibility allows these materials to integrate more effectively with surrounding tissues, promoting their acceptance by the body and minimizing the risk of rejection or inflammation. This study is focused on investigations of the surface properties of polyelectrolyte layers, micelles, and complex systems utilizing red blood cells (RBCs) as carriers for growth factors. Through electrostatic interactions between negatively charged RBCs and positively charged polyelectrolytes, it becomes possible to modify red blood cells for use as effective delivery systems. Additionally, polyelectrolyte micelles can be employed for delivery purposes through grafting with suitable polymers. All of the tested surfaces exhibited hydrophilic characteristics, as indicated by measurements of the contact angle. Furthermore, the study determined the zeta potential of modified red blood cells and presented methods for the docking of vascular endothelial growth factor (VEGF) onto both RBCs and micelles. The obtained results highlight the potential of these biofunctionalized systems for improving therapeutic outcomes in regenerative medicine and drug delivery.

Ocena wybranych właściwości mechanicznych i fizycznych akrylowych cementów kostnych o niskiej lepkości

Zając Zuzanna, Łagan Sylwia, Liber-Kneć Aneta

Aktualne Problemy Biomechaniki

2023

z. 23

35--42

The aim of this work was comparison mechanical and physical properties of bone cements used in human and animal orthopedics. The mechanical properties were determined by compression tests, a contact angle was observed with a goniometer and the surface free energy was calculated by Owens-Wendt model. Two states of material (initial and after incubation) were considered. The incubation process changed the nature of the surface to hydrophilic and caused an increase in the polar component of the surface free energy. The obtained compression curves are similar, showing both linear and plastic regions, with an conventional yield point.

Celem pracy było porównanie właściwości mechanicznych i fizycznych powierzchni cementów kostnych stosowanych w ortopedii. Właściwości mechaniczne określono za pomocą statycznej próby jednoosiowego ściskania, kąt zwilżania wyznaczano przy użyciu goniometru optycznego, a swobodną energię powierzchniową obliczono według modelu Owensa-Wendta. Rozpatrzono dwa stany materiału (początkowy i po inkubacji). Proces inkubacji zmienił charakter powierzchni na hydrofilowy i spowodował wzrost wartości składowej polarnej swobodnej energii powierzchniowej. Otrzymane krzywe ściskania dla badanych stanów są podobne, ukazując obszar liniowy, jak i plastyczny, z umowną granicą plastyczności.