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1

Biofunctional impact of textured coatings in the application of heart assist therapy

Kurtyka Przemysław, Kopernik Magdalena, Kaczmarek Marcin, Surmiak Marcin, Major Łukasz, Kustosz Roman, Więcek Justyna, Kurtyka Klaudia, Bartkowiak Amanda, Major Roman

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e31, 2023

EN

Due to a lack of organs, cardiac support systems are being implanted in patients with severe congestive heart failure. One of the solutions to overcome complications such as infow obstruction or pump thrombosis, which may occur in the case of ventricular assist devices, is to modify the surface of cannulas for the controlled blood clotting process. The results obtained up till now for developed surface coatings clearly show the influence of topographical and mechanical parameters of the coatings on cell viability and protein adsorption mechanism. The new coatings should enable the controlled growth of scar tissue, resulting in the limitation of thromboembolic events, and the reduction of cystic tissue growth into the fow lumen. The aim of this study is to evaluate the correlation between surface topography parameters on the susceptibility of cells to grow and adhere to the substrate as a solution with potential for use in MCS (mechanical circulatory support) devices. Research on surfaces used in MCS devices and on inflow cannulas has been carried out for many years, while the novelty of the present solution makes it a milestone within that type of application simultaneously allowing for appropriate selection of process parameters. Surface modifcation of titanium alloy Ti6Al7Nb was carried out using vacuum powder sintering of CP-Ti (commercially pure titanium) powder with two morphologies (regular spheres and irregular grains). The characterization of coatings obtained with the proposed method and the influence of measured topographic parameters (applying scanning electron microscopy, contact angle measurement and contact proflometry) on the cytotoxicity and susceptibility to protein adsorption were presented. Advanced albumin adsorption studies have fully confrmed the dependence of surface complexity on protein adsorption. The obtained results show a high potential of the produced coatings toward enabling permanent integration at the implant with the soft tissue.

2

Badania adsorpcji białek na powierzchni biomasy w procesie enzymatycznej hydrolizy słomy kukurydzianej do fermentowalnych cukrów prostych

Dąbkowska K., Sobieszuk P., Pilarek M.

Przemysł Chemiczny

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2017

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T. 96, nr 11

2301--2304

PL

Przedstawiono wyniki analizy adsorpcji białek zawartych w przemysłowym celulolitycznym preparacie enzymatycznym na poddanej obróbce wstępnej biomasie słomy kukurydzianej. Słoma kukurydziana i wyizolowana z niej lignina zostały użyte jako substraty w procesie enzymatycznego uwalniania cukrów prostych. Obróbkę wstępną biomasy prowadzono w środowisku alkalicznego 2-proc. roztworu H₂O₂ (pH 11,5). Wyznaczono wydajność hydrolizy glukanów (uzyskano 80,5%) i ksylanów (88,2%), stanowiących frakcje wstępnie obrobionej biomasy. Wyniki badań adsorpcji białek enzymatycznych na cząstkach surowca oraz ligninie opisano modelami izotermy Langmuira. Na podstawie tego modelu wyznaczono izotermy adsorpcji enzymów na polisacharydach zawartych w biomasie surowca.

EN

Corn straw biomass was pretreated with H₂O2₂ in alk. medium and then hydrolyzed in presence of a com. enzyme formulation at 50°C to produce glucose and xylose (yields 80.5% and 88.2%, resp.). The adsorption of enzymes on the raw material was described with Langmuir model isotherms.

3

In vitro hemocompatibility of thin films materials for direct blood contact

Trembecka-Wójciga K., Major R., Lackner J. M., Plutecka H.

Engineering of Biomaterials

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2015

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Vol. 18, no. 132

2--8

EN

When designing new biomaterials for tissue contact devices it is important to consider their architecture as it affects different cell response. Surface modification of tubular structures requires the use of different techniques than in the case of flat samples. Similarly, analytical techniques also need to be adapted to the specific shape of substrate. For blood contacting devices this issue is critical because of shear forces generated by fluid flow and responsible for blood components activation. This necessitates the use of diagnostic techniques dedicated for material analysis in dynamic conditions in order to simulate physiological conditions. In the frame of the work, the flat samples as well as tube like elements were considered. The flat samples were prepared for basic research. Based on the results of the basic research the thin coatings were selected for the internal side of the tube like elements which have been analysed in contact with blood using blood flow simulator. The cross section of the coating-substrate interaction was tested using transmission electron microscopy. The attachment of cells to coatings was determined by radial flow chamber. Hemocompatible analysis was carried out in two ways. The quality of the blood after the dynamic test was analysed using flow cytometry. In this case the aggregates formation, platelet consumption and apoptosis derived microparticles were considered. The amount of cells adhered to the materials surfaces was determined by confocal laser microscopy.

4

Antifouling surfaces in medical application

Utrata-Wesołek A.

Polimery

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2013

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T. 58, nr 9

685--695

EN

The uncontrolled adhesion of biological compounds on the surface of implant materials is a harmful phenomenon that causes the function of medical devices to deteriorate. The design of surfaces that resist nonspecific protein, cell or bacteria adsorption (so-called antifouling surfaces) is of special interest as it is critical for the development of medical devices that have contact with physiological fluids. Significant efforts have been made in coating surfaces with bioinert macromolecules. Both self-assembled monolayers (SAM) and polymer brushes have attracted considerable attention due to their facile synthesis, their diverse physicochemical properties (composition, molar mass or topology) and their tunable surface chemistry (film thickness, grafting density, conformation and flexibility). In this article, a general description of surfaces with nonfouling properties is provided. Two basic classes of nonfouling polymers (hydrophilic and zwitterionic) are discussed with a series of practical examples.

PL

Artykuł stanowi przegląd literaturowy dotyczący powierzchni przeciwdziałających osadzaniu się związków biologicznie aktywnych. Niekontrolowana adhezja związków biologicznie aktywnych na powierzchni implantów to niekorzystne zjawisko pogarszające prawidłowe funkcjonowanie wszczepialnych urządzeń medycznych. Kluczowa więc jest możliwość utworzenia powierzchni odpornych na adhezję białek, komórek bądź bakterii (tzw. powierzchni przeciwdziałających osadzaniu się związków biologicznie aktywnych). W ostatnich latach dużym zainteresowaniem cieszą się powierzchnie zdolne do przeciwdziałania adsorpcji, pokryte powłoką wytworzoną na bazie biokompatybilnych i nietoksycznych polimerów. Najwięcej uwagi poświęcono samoorganizującym się warstwom (SAM) i powierzchniom ze szczepionymi łańcuchami polimerowymi. Zainteresowanie to wynika ze stosunkowo łatwej syntezy powierzchni, różnorodności fizykochemicznych właściwości stosowanych polimerów (skład, masa molowa i topologia) oraz samej powierzchni polimeru (grubość warstwy, gęstość szczepienia, konformacja łańcuchów). Omówiono dwie podstawowe klasy polimerów przeciwdziałających adhezji białek — hydrofilowe polimery oraz polimery zawierające jony obojnacze.

5

Biomimetic Ca-P coatings obtained by chemical/electrochemical methods from Hanks' solution on a Ti surface

Pisarek M., Roguska A., Marcon L., Andrzejczuk M.

Engineering of Biomaterials

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2012

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Vol. 15, no. 113

29--32

EN

The purpose of this study was to investigate the bioactivity of porous calcium phosphate coatings on titanium prepared using a two-step procedure (chemical etching or anodic oxidation of Ti followed by soaking in simulated body fluid or direct electrodeposition from Hanks' solution). In order to evaluate the potential use of the coatings for biomedical applications, the adsorption of serum albumin, the most abundant protein in the blood, and the attachment of living cells (osteoblasts, U2OS) were studied.

6

Charakterystyka nanoporowatych warstw na Ti jako perspektywicznych podłoży dla zastosowań biomedycznych

Pisarek M., Roguska A., Andrzejczuk M.

Inżynieria Materiałowa

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2011

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Vol. 32, nr 2

71-76

PL

Nanorurki (NT) tlenku tytanu o długości około 1 ?m i średnicy w zakresie od 40 do 110 nm wytworzono na Ti metodą utleniania anodowego przy stałym potencjale (10, 15, 20 i 25 V) w roztworze gliceryny i wody dejonizowanej z dodatkiem 0,86% mas. fluorku amonu. Do scharakteryzowania samoorganizujących się porowatych warstw na Ti oraz wpływu temperatury wygrzewania w zakresie 200÷600°C na ich morfologię, strukturę i mechaniczną stabilność wykorzystano elektronową mikroskopię skaningową, elektronową mikroskopię transmisyjną, dyfrakcję rentgenowską oraz spektroskopię fotoelektronów. Na powierzchni termicznie stabilizowanych nanorurek TiO2 zaadsorbowano proteiny w celu wstępnej oceny biozgodności tak przygotowanych podłoży. Przeprowadzone badania wykazały, iż porowate warstwy tlenkowe uzyskiwały stabilność po wygrzewaniu w temperaturze powyżej 400°C, a ich struktura ulegała zmianie z amorficznej na krystaliczną (anataz + rutyl). Tak zmodyfikowana powierzchnia Ti okazała się obiecującym podłożem do adsorpcji protein w porównaniu z powierzchnią typowego implantu z czystego Ti.

EN

Titanium oxide nanotube arrays were fabricated in a mixture of glycerol, deionized water and low concentration solution of NH4F (0.86 wt %). Well- -ordered nanotube arrays of titania with length of ~1.0 ?m and diameter of about 40÷110 nm were prepared via electrochemical oxidation at constant voltage (10, 15, 20 or 25 V). SEM, X-ray diffraction, FTIR spectroscopy and XPS surface analytical technique were used to characterize the self-organized porous layers, and the effect of annealing at 200÷600°C on their morphology, structure and mechanical stability. Thermally stabilized TiO2 nanotubes were used for adsorption of the protein on their surfaces. Our results showed, that the nanotubular structure was stable above the 400°C and their structure changed from amorphous to the crystalline phase (anatase + rutile). Surface of Ti modified as presented in the article appeared a promising substrates for protein adsorption, as compared to a typical Ti implant surfaces.

7

Interaction of parylene C with biological objects

Kamińska M., Okrój W., Szymański W., Jakubowski W., Komorowski P., Nosal A., Szymanowski H., Gazicki-Lipman M., Jerczyńska H., Pawłowska Z., Walkowiak B.

Acta of Bioengineering and Biomechanics

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2009

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Vol. 11, nr 3

19-25

EN

The aim of the present work was to examine the interactions of parylene C with such selected biological objects as: blood plasma proteins, platelets, endothelial cells, and bacterial biofilm produced by E. coli cells. The results obtained strongly support the thesis that parylene C is a material worth considering for biomedical use. Parylene C coating on polished medical steel significantly reduces platelet adhesion to this surface. On the other hand, in the case of the surface of machined medical steel coated with parylene C, the number of adhered platelets is significantly higher. This also means that surface texture of substrate material is very well reproduced by parylene C coating and is an important factor facilitating the platelet adhesion. Adsorption of plasma proteins at parylene C surface is very effective, and this finding confirms a notion that cell interaction with surfaces is mediated by the adsorbed proteins. In the light of the above, a high susceptibility of parylene C surface to bacterial colonization is easy to explain. The results showing reduced proliferation and changes in endothelial cell gene expression should also be seriously analysed when parylene C is considered for the use in contact with blood vessels.

8

Irreversible adsorption of colloids and proteins at heterogeneous surfaces

Adamczyk Z., Weroński P., Musiał E.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 2

175-187

EN

Irreversible adsorption of colloid particles at heterogeneous surfaces was studied theoretically. In contrast to previous models, the dimension of the adsorption sites having the shape of circular discs, was comparable with the size of adsorbing spheres. Adsorption was assumed to occur if the sphere contacted the disc only. Numerical simulation of the Monte-Carlo type enabled one to determine particle flux, adsorption kinetics and jamming coverage as a function of the site density (coverage) and the size ratio particle/site, denoted by lambda . It was demonstrated that adsorption kinetics and the jamming coverage increased significantly, at a fixed site density, when lambda increased, i.e., for larger particle to site size ratio. It was also proven that the results derived from previous model elaborated for negligible site dimensions are valid only if lambda > 10.

9

Protein adsorption, cell adhesion and polymer surfaces: molecular processes and experimental methods

Rouxhet P. G., Dewez J.-L., Marchal T., Dupont-Gillain C., Dufrene Y.

Inżynieria Biomateriałów

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1999

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R. 2, nr 7-8

4--7

EN

Adsorption of extracellular matrix (ECM) proteins in competition with other substances is a key to explain the relationship between substratum surface hydrophobicity and mammalian cell adhesion: when polystyrene substrata were exposed simultanously to ECM protein and a PEO-PPO-PEO polymer surfactant (Płuronic F68), either by pre-conditioning or through protein cell secretion, a weaker substratum hydrophobicity favoured adsorption of the protein and subsequent cell adhesion. This knowledge was used to achieve a selective adhesion of different types of mammalian cells on tracks (a few tens of μm wide) produced on polystyrene by photolithography and oxygen plasma treatment. conditioning the substraturn with a solution of ECM protein and Pluronic F68. Examination of a broader range of substrata confirmed that inhibition of cell adhesion on hydrophobic substrata is due to adsorption of substances competing with extracellular matrix proteins. However it also showed that substratum surface properties more subtle than overall wettability are important. In situ observation of the nanoscale organisation of collagen adsorbed in the absence of competitor, using atomic force microscopy (AFM), showed that a smooth substratum surface allows collagen mobility and aggregation of molecular ends in the adsorbed phase. The organisation obtained after drying (smooth film, pattern) was examined by combining AFM, XPS and radiolabelling and found to be influenced by substratum hydrophobicity and drying rate.