Novel protein-repellent and antimicrobial polysaccharide multilayer thin films

Abstract Nanostructured and bio-active polysaccharide-based thin films were manufactured by means of subsequent spin-coated deposition of a regenerated cellulose (RC) layer and a 2,2,6,6-Tetramethylpiperidine-1-oxyl radical (TEMPO) oxidised cellulose nanofibril (TOCN) layer. The bio-activity of the bilayer was achieved by addition of chitosan (CS). The chitosan was either mixed with the TOCN (TOCN+CS) and deposited on the RC layer by spin-coating, or deposited on the RC and TOCN bilayer by pumping its aqueous solution with various pH over the surface of the bilayer. The water content of the thin films and the CS interactions with the bilayer during deposition were studied in situ by means of a quartz crystal microbalance with dissipation (QCM-D). The pH dependent charging behaviour of the TOCN, TOCN+CS and CS dispersions was evaluated by pH-potentiometric titrations. The surface morphology of the thin films was characterised by atomic force microscopy (AFM). The bio-activity of the thin films was evaluated by studying their protein-repellent properties in situ with a continuous flow of bovine serum albumin (BSA) by means of QCM-D and by evaluating their antibacterial properties in vitro against Staphylococcus aureus and Escherichia coli. These polysaccharide-based thin films are high value-added products because of their multifunctionality, high water absorbance capacity, protein-repellence and antimicrobial activity, and have the potential for medical application as a wound dressing material.

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Atomic force microscopy of in situ deformed nickel thin films

Thin Solid Films ◽

10.1016/s0040-6090(99)00369-7 ◽

1999 ◽

Vol 353 (1-2) ◽

pp. 194-200 ◽

Cited By ~ 43

Author(s):

C. Coupeau ◽

J.F. Naud ◽

F. Cleymand ◽

P. Goudeau ◽

J. Grilhé

Keyword(s):

Thin Films ◽

Atomic Force Microscopy ◽

Force Microscopy ◽

Nickel Thin Films ◽

Atomic Force

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In-situ electrochemical atomic force microscopy study of aging of magnetron sputtered Pt-Co nanoalloy thin films during accelerated degradation test

Electrochimica Acta ◽

10.1016/j.electacta.2016.06.035 ◽

2016 ◽

Vol 211 ◽

pp. 52-58 ◽

Cited By ~ 17

Author(s):

Ivan Khalakhan ◽

Mykhailo Vorokhta ◽

Michal Václavů ◽

Břetislav Šmíd ◽

Jaroslava Lavková ◽

...

Keyword(s):

Thin Films ◽

Atomic Force Microscopy ◽

Microscopy Study ◽

Atomic Force Microscopy Study ◽

Force Microscopy ◽

Accelerated Degradation ◽

Atomic Force ◽

Degradation Test ◽

Accelerated Degradation Test

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The Physicochemical and Antibacterial Properties of Chitosan-Based Materials Modified with Phenolic Acids Irradiated by UVC Light

International Journal of Molecular Sciences ◽

10.3390/ijms22126472 ◽

2021 ◽

Vol 22 (12) ◽

pp. 6472

Author(s):

Beata Kaczmarek-Szczepańska ◽

Marcin Wekwejt ◽

Olha Mazur ◽

Lidia Zasada ◽

Anna Pałubicka ◽

...

Keyword(s):

Thin Films ◽

Antimicrobial Activity ◽

Ferulic Acid ◽

Phenolic Acid ◽

Food Packaging ◽

Antibacterial Properties ◽

Force Microscopy ◽

Atomic Force ◽

Before And After

This paper concerns the physicochemical properties of chitosan/phenolic acid thin films irradiated by ultraviolet radiation with wavelengths between 200 and 290 nm (UVC) light. We investigated the preparation and characterization of thin films based on chitosan (CTS) with tannic (TA), caffeic (CA) and ferulic acid (FA) addition as potential food-packaging materials. Such materials were then exposed to the UVC light (254 nm) for 1 and 2 h to perform the sterilization process. Different properties of thin films before and after irradiation were determined by various methods such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM), differential scanning calorimeter (DSC), mechanical properties and by the surface free energy determination. Moreover, the antimicrobial activity of the films and their potential to reduce the risk of contamination was assessed. The results showed that the phenolic acid improving properties of chitosan-based films, short UVC radiation may be used as sterilization method for those films, and also that the addition of ferulic acid obtains effective antimicrobial activity, which have great benefit for food packing applications.

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Surface Structural Characterization and Mechanical Testing by Nanoindentation Measurements of Hybrid Polymer/clay Nanostructured Multilayer Films

Journal of Materials Research ◽

10.1557/jmr.2002.0240 ◽

2002 ◽

Vol 17 (7) ◽

pp. 1622-1633 ◽

Cited By ~ 20

Author(s):

Xiaowu Fan ◽

Mi-Kyoung Park ◽

Chuanjun Xia ◽

Rigoberto Advincula

Keyword(s):

Thin Films ◽

Quartz Crystal ◽

Ex Situ ◽

Multilayer Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Diallyldimethylammonium Chloride

Nanostructured montmorillonite/poly(diallyldimethylammonium chloride) multilayer thin films were fabricated up to 100 layers thick by stepwise alternating polyelectrolyte and clay deposition from solution. The structure and morphology of the films were characterized by x-ray diffraction, ellipsometry, atomic force microscopy, and quartz crystal microbalance ex situ and in situ measurements. The mechanical properties were tested by nanoindentation. The hardness of the multilayer thin film was 0.46 GPa. The thin film's modulus was correlated to its ordering and anisotropic structure. Both hardness and modulus of this composite film were higher than those of several other types of polymer thin films.

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Atomic force microscopy studies of ZnS films grown on (100) GaAs by the successive ionic layer adsorption and reaction method

Journal of Materials Research ◽

10.1557/jmr.1998.0233 ◽

1998 ◽

Vol 13 (6) ◽

pp. 1688-1692 ◽

Cited By ~ 10

Author(s):

Mika P. Valkonen ◽

Seppo Lindroos ◽

Tapio Kanniainen ◽

Markku Leskelä ◽

Roland Resch ◽

...

Keyword(s):

Thin Films ◽

Atomic Force Microscopy ◽

Thin Film Deposition ◽

Film Deposition ◽

Force Microscopy ◽

Atomic Force ◽

Layer Adsorption ◽

Silar Technique ◽

Ionic Layer

In this study zinc sulfide thin films were grown by the successive ionic layer adsorption and reaction (SILAR) technique on (100) GaAs substrates from aqueous precursor solutions. The atomic force microscopy (AFM) method was used to study the growth of the films up to a thickness of 180 nm. The ZnS thin films on (100) GaAs were smooth with an rms roughness of 0.2–1.9 nm depending on the film thickness. After the GaAs surface was covered with ZnS, the growth appeared to be nearly layerwise. In addition, in situ AFM studies were carried out to analyze the dissolution of (100) GaAs in water, which is a process competing with the thin film deposition by the SILAR.

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Dielectric and Electromechanical Behaviour of Relaxor [(1−x)Pb(Mg1/3Nb2/3)O3 -xPbTiO3] Thin Films

MRS Proceedings ◽

10.1557/proc-688-c10.2.1 ◽

2001 ◽

Vol 688 ◽

Author(s):

N.J. Donnelly ◽

G. Catalan ◽

C. Morros ◽

R.M. Bowman ◽

J.M. Gregg

Keyword(s):

Thin Films ◽

Single Crystal ◽

Plane Strain ◽

X Ray Diffraction ◽

Force Microscopy ◽

Bulk Ceramic ◽

Atomic Force ◽

Out Of Plane ◽

Order Of Magnitude

AbstractThin film capacitor structures of Au / (1−x)Pb(Mg1/3Nb2/3)O3 - xPbTiO3 /(La1/2Sr1/2)CoO3 were fabricated by pulsed laser deposition on single crystal {001} MgO substrates. Films were found to be perovskite dominated and highly {001} oriented. Dielectrically, films displayed relaxorlike features, though maximum permittivity was low compared to single crystal or bulk ceramic (∼1400 at peak @1kHz, for x=0.07, 0.1 & 0.2). A field induced piezoelectric coefficient d33 was measured by piezoresponse atomic force microscopy for specific compositions x =0, × =0.07, and x =0.1 and found to be disappointingly low - indicating poor electric field induced strain. Despite this macroscopic electrostrictive coefficients Q33 were found to be (3.6 ± 0.6) ×10−2C−2m4, (2.6 ± 0.2) ×10−2C−2m4, and (0.9 ± 0.3) ×10−2C−2m4 respectively. Crystallographic electrostrictive coefficients were determined by in-situ x-ray diffraction and found to be (4.9 ± 0.2) ×10−2C−2m4 for PMN-(0.07)PT and (1.9 ± 0.1) ×10−2C−2m4 for PMN-(0.1)PT. Considering that all these Q33 values are of the same order of magnitude as found in single crystal experiments (2.5 – 3.8 ×10−2C−2m4), it is suggested that low out-of-plane strain is entirely a result of reduced polarisability rather than reduced electrostrictive coefficients in thin films relative to bulk ceramic or single crystal. An estimate was also made of the Q13 electrostrictive coefficient for PMN and PMN-(0.07)PT by measuring permittivity as a function of applied in-plane strain. The values obtained were -1.31 ×10−2C−2m4 and -0.46 ×10−2C−2m4 respectively.

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Deposition mechanism of nanostructured thin films from tetrafluoroethylene glow discharges

Pure and Applied Chemistry ◽

10.1351/pac200577020399 ◽

2005 ◽

Vol 77 (2) ◽

pp. 399-414 ◽

Cited By ~ 46

Author(s):

A. Milella ◽

F. Palumbo ◽

P. Favia ◽

G. Cicala ◽

R. d’Agostino

Keyword(s):

Thin Films ◽

Film Growth ◽

Water Repellency ◽

High Water ◽

Experimental Conditions ◽

Deposition Mechanism ◽

Force Microscopy ◽

Glow Discharges ◽

Atomic Force ◽

Surface Migration

Nanostructured polytetrafluoroethylene (PTFE)-like thin films can be deposited, in certain experimental conditions, by modulated discharges fed with tetrafluoroethylene (TFE). These coatings are characterized by a unique morphology consisting of highly twisted micron-long ribbons, which leads to an extremely high water repellency of the surface. In the present work, the diagnostics of the plasma phase is presented, coupled with that of the coating, in order to understand the film growth mechanism in different discharge regimes. When the duty cycle (DC) is increased in modulated C2F4 plasmas, the monomer depletion increases, too, and many recombination reactions take place at progressively higher rates, resulting in the formation of CF4, C2F6, C3F6, C3F8, and C4F10; the formation of powders in the homogeneous phase, however, was never evidenced. The modulation of C2F4 plasmas strongly affects the morphology of the resulting coating, as revealed by atomic force microscopy (AFM), ranging from bumpy to ribbon-like structures. The latter, moreover, are found to be more PTFE-like with respect to the remaining part of the film. In the last part of the paper, a deposition mechanism is proposed, where low radical densities in the plasma and surface migration of the precursors are the keys for the growth of ribbon-like structures.

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Microstructure, Properties and Biocompatibility of the Nitrided Ti-6Al-4V Alloy for Medical Application

Materials Science Forum ◽

10.4028/www.scientific.net/msf.513.15 ◽

2006 ◽

Vol 513 ◽

pp. 15-24 ◽

Cited By ~ 1

Author(s):

A. Czyrska-Filemonowicz ◽

P.A. Buffat ◽

E. Czarnowska ◽

Tadeusz Wierzchoń

Keyword(s):

Surface Topography ◽

Bulk Material ◽

Medical Application ◽

Clear Correlation ◽

Corrosion Properties ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron

Investigation of the microstructure, properties and biocompatibility of the Ti-6Al-4V alloy nitrided under glow discharge was performed. The microstructural analyses were carried out using light microscopy, X-ray diffraction, analytical scanning and transmission electron microscopy. Phase identifications and chemical composition of the layer and bulk material (substrate) were determined by electron diffraction and energy dispersive X-ray spectrometry. Atomic force microscopy was applied for layer surface topography measurements. Microhardness and Young’s modulus measurements as well as frictional wear resistance and corrosion resistance tests were performed. The investigation revealed a clear correlation between the micro/nanostructure and surface topography of the layer with its micromechanical, tribological and corrosion properties. In-vitro examinations of biofilm and cell behaviour show that the nitrided Ti-6Al-4V alloy exhibits good biocompatibility.

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