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Eriksson M, Claesson PM, Järn M, Wallqvist V, Tuominen M, Kappl M, Teisala H, Vollmer D, Schoelkopf J, Gane PA, Mäkelä JM, Swerin A. Effects of Gas Layer Thickness on Capillary Interactions at Superhydrophobic Surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:4801-4810. [PMID: 38386540 PMCID: PMC10919075 DOI: 10.1021/acs.langmuir.3c03709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/12/2024] [Accepted: 02/13/2024] [Indexed: 02/24/2024]
Abstract
Strongly attractive forces act between superhydrophobic surfaces across water due to the formation of a bridging gas capillary. Upon separation, the attraction can range up to tens of micrometers as the gas capillary grows, while gas molecules accumulate in the capillary. We argue that most of these molecules come from the pre-existing gaseous layer found at and within the superhydrophobic coating. In this study, we investigate how the capillary size and the resulting capillary forces are affected by the thickness of the gaseous layer. To this end, we prepared superhydrophobic coatings with different thicknesses by utilizing different numbers of coating cycles of a liquid flame spraying technique. Laser scanning confocal microscopy confirmed an increase in gas layer thickness with an increasing number of coating cycles. Force measurements between such coatings and a hydrophobic colloidal probe revealed attractive forces caused by bridging gas capillaries, and both the capillary size and the range of attraction increased with increasing thickness of the pre-existing gas layer. Hence, our data suggest that the amount of available gas at and in the superhydrophobic coating determines the force range and capillary growth.
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Affiliation(s)
- Mimmi Eriksson
- Materials
and Surface Design, RISE Research Institutes
of Sweden, SE-11486 Stockholm, Sweden
- Department
of Chemistry, Division of Surface and Corrosion Science, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden
- CR
Colloidal Resource AB, Naturvetarvägen 14, SE-22362 Lund, Sweden
| | - Per M. Claesson
- Department
of Chemistry, Division of Surface and Corrosion Science, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden
| | - Mikael Järn
- Materials
and Surface Design, RISE Research Institutes
of Sweden, SE-11486 Stockholm, Sweden
| | - Viveca Wallqvist
- Materials
and Surface Design, RISE Research Institutes
of Sweden, SE-11486 Stockholm, Sweden
| | - Mikko Tuominen
- Materials
and Surface Design, RISE Research Institutes
of Sweden, SE-11486 Stockholm, Sweden
- Nordtreat
Oy, Mestarintie 11, FI-01730 Vantaa, Finland
| | - Michael Kappl
- Department
of Physics at Interfaces, Max Planck Institute
for Polymer Research, D-55128 Mainz, Germany
| | - Hannu Teisala
- Department
of Physics at Interfaces, Max Planck Institute
for Polymer Research, D-55128 Mainz, Germany
- Amcor
Flexibles Valkeakoski Oy, Niementie 161, P.O. Box 70, 37601 Valkeakoski, Finland
| | - Doris Vollmer
- Department
of Physics at Interfaces, Max Planck Institute
for Polymer Research, D-55128 Mainz, Germany
| | | | - Patrick A.C. Gane
- School
of Chemical Engineering, Department of Bioproducts and Biosystems, Aalto University, FI-00076 Aalto, Finland
- Faculty of
Technology and Metallurgy, University of
Belgrade, Karnegijeva
4, Belgrade 11000, Serbia
| | - Jyrki M. Mäkelä
- Physics
Unit, Aerosol Physics Laboratory, Tampere
University, Tampere FI-33014, Finland
| | - Agne Swerin
- Department
of Chemistry, Division of Surface and Corrosion Science, KTH Royal Institute of Technology, SE-10044 Stockholm, Sweden
- Department
of Engineering and Chemical Sciences, Karlstad
University, SE-651 88 Karlstad, Sweden
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2
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Provenzano M, Bellussi FM, Morciano M, Asinari P, Fasano M. Method for predicting the wettability of micro-structured surfaces by continuum phase-field modelling. MethodsX 2023; 11:102458. [PMID: 37954967 PMCID: PMC10638050 DOI: 10.1016/j.mex.2023.102458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/29/2023] [Accepted: 10/20/2023] [Indexed: 11/14/2023] Open
Abstract
Numerical prediction of material properties is attracting the attention of the scientific community and industry because of its usefulness in the design process. In the fields of fluid dynamics and microfluidics, several simulation methods have been proposed and adopted to evaluate the properties of surfaces and material interfaces, thanks to the increasing computational power available. However, despite the efforts made, a general and standardized methodology for implementing such methods is still lacking, thus requiring a trial-and-error approach for each new problem, making them difficult to implement and creating a bottleneck at the initial stage of surface design. Here, we report a validated protocol to evaluate the wettability of micro-structured surfaces with a phase-field model. Summarizing:•Simulating physical phenomena with multi-phase flows and moving contact lines can be a challenging task, due to the coupling among disparate length scales.•Using the Cahn-Hilliard diffuse-interface model, moving contact lines can be extensively investigated, although difficulties may arise when implementing numerical simulations, e.g., model parameter calibration, selection of boundary conditions, post-processing of fluid dynamics/equilibrium.•A method for employing this model and evaluating the physical consistency of the results is proposed here, considering the wettability of micro-structured surfaces as a case study.
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Affiliation(s)
- Marina Provenzano
- Department of Energy, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino, 10129, Italy
| | | | - Matteo Morciano
- Department of Energy, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino, 10129, Italy
| | - Pietro Asinari
- Department of Energy, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino, 10129, Italy
- Istituto Nazionale di Ricerca Metrologica, Strada delle Cacce 91, Torino, 10135, Italy
| | - Matteo Fasano
- Department of Energy, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino, 10129, Italy
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3
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Üçüncüoğlu R, Erbil HY. Water Drop Evaporation on Slippery Liquid-Infused Porous Surfaces (SLIPS): Effect of Lubricant Thickness, Viscosity, Ridge Height, and Pattern Geometry. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:6514-6528. [PMID: 37103333 PMCID: PMC10173461 DOI: 10.1021/acs.langmuir.3c00471] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 04/11/2023] [Indexed: 05/10/2023]
Abstract
Sessile drop evaporation and condensation on slippery liquid-infused porous surfaces (SLIPS) is crucial for many applications. However, its modeling is complex since the infused lubricant forms a wetting ridge around the drop close to the contact line, which partially blocks the free surface area and decreases the drop evaporation rate. Although a good model was available after 2015, the effects of initial lubricant heights (hoil)i above the pattern, and the corresponding initial ridge heights (hr)i, lubricant viscosity, and solid pattern type were not well studied. This work fills this gap where water drop evaporations from SLIPS, which are obtained by infusing silicone oils (20 and 350 cSt) onto hydrophobized Si wafer micropatterns having both cylindrical and square prism pillars, are investigated under constant relative humidity and temperature conditions. With the increase of (hoil)i, the corresponding (hr)i increased almost linearly on lower parts of the drops for all SLIPS samples, resulting in slower drop evaporation rates. A novel diffusion-limited evaporation equation from SLIPS is derived depending on the available free liquid-air interfacial area, ALV, which represents the unblocked part of the total drop surface. The calculation of the diffusion constant, D, of water vapor in air from (dALV/dt) values obtained by drop evaporation was successful up to a threshold value of (hoil)i = 8 μm within ±7%, and large deviations (13-27%) were obtained when (hoil)i > 8 μm, possibly due to the formation of thin silicone oil cloaking layers on drop surfaces, which partially blocked evaporation. The increase of infused silicone oil viscosity caused only a slight increase (12-17%) in drop lifetimes. The effects of the geometry and size of the pillars on the drop evaporation rates were minimal. These findings may help optimize the lubricant oil layer thickness and viscosity used for SLIPS to achieve low operational costs in the future.
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Affiliation(s)
- Rana Üçüncüoğlu
- Department of Chemical Engineering, Gebze Technical University, Gebze, 41400 Kocaeli, Türkiye
| | - H. Yildirim Erbil
- Department of Chemical Engineering, Gebze Technical University, Gebze, 41400 Kocaeli, Türkiye
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4
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Wang L, Wang H, Di Y, Dong L, Jin G. Predicting Sliding Angles on Random Pit-Distributed Textures Using Probabilistic Neural Networks. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:6406-6412. [PMID: 37095072 DOI: 10.1021/acs.langmuir.3c00188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The three-phase contact line best reflects the sliding ability of droplets on solid surfaces. Most studies on the sliding angle (SA) of superhydrophobic surfaces are limited to regularly arranged microtextured surfaces, lacking definite models and effective methods for a complex surface of a random texture. In this study, random pits with an area ratio of 19% were generated on 1 mm × 1 mm subregions, and the subregions formed arrays on a sample surface of 10 mm × 10 mm to obtain a randomly distributed microtexture surface with no pit overlaps. Although the contact angle (CA) of randomly pitted texture was the same, the SA was different. The SA of surfaces was affected by the pit location. The location of random pits increased the complexity of the three-phase contact line movement. The continuity of the three-phase contact angle (T) can reveal the rolling mechanism of the random pit texture and predict the SA, but the relationship between the T and SA is a relatively poor linear relation (R2 = 74%), and the SA of the random pit texture can only be roughly estimated. The quantized pit coordinates and SA were used as the input and output labels for the PNN model, respectively, and the accuracy of the model convergence was 90.2%.
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Affiliation(s)
- Li Wang
- College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150090, Heilongjiang, China
- Key Laboratory of National Defense Science and Technology for Equipment Remanufacturing Technology, Army Armored Forces Academy, Beijing 100072, China
| | - Haidou Wang
- College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150090, Heilongjiang, China
- National Engineering Research Center for Remanufacturing, Army Armored Forces Academy, Beijing 100072, China
| | - Yuelan Di
- Key Laboratory of National Defense Science and Technology for Equipment Remanufacturing Technology, Army Armored Forces Academy, Beijing 100072, China
| | - Lihong Dong
- Key Laboratory of National Defense Science and Technology for Equipment Remanufacturing Technology, Army Armored Forces Academy, Beijing 100072, China
| | - Guo Jin
- College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150090, Heilongjiang, China
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5
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Surface Properties of Graffiti Coatings on Sensitive Surfaces Concerning Their Removal with Formulations Based on the Amino-Acid-Type Surfactants. Molecules 2023; 28:molecules28041986. [PMID: 36838974 PMCID: PMC9958821 DOI: 10.3390/molecules28041986] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/15/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
Water-in-oil (w/o) nanoemulsions stabilized with amino acid surfactants (AAS) are one example of nanotechnology detergents of the "brush on, wipe off"-type for removing graffiti coatings from different sensitive surfaces. The high-pressure homogenization (HPH) process was used to obtain the nanostructured fluids (NSFs), including the non-toxic and eco-friendly components such as AAS, esterified vegetable oils, and ethyl lactate. The most effective NSF detergent was determined by response surface methodology (RSM) optimization. Afterwards, several surface properties, i.e., topography, wettability, surface free energy, and the work of water adhesion to surfaces before and after their coverage with the black graffiti paint, as well as after the removal of the paint layers by the eco-remover, were determined. It was found that the removal of graffiti with the use of the NSF detergent is more dependent on the energetic properties and microporous structure of the paint coatings than on the properties of the substrates on which the layers were deposited. The use of NSFs and knowledge of the surface properties could enable the development of versatile detergents that would remove unwanted contamination from various surfaces easily and in a controlled way.
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6
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Graffiti coating eco-remover developed for sensitive surfaces by using an optimized high-pressure homogenization process. Colloids Surf A Physicochem Eng Asp 2023. [DOI: 10.1016/j.colsurfa.2022.130792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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7
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Tümer EH, Erbil HY, Akdoǧan N. Wetting of Superhydrophobic Polylactic Acid Micropillared Patterns. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:10052-10064. [PMID: 35930742 PMCID: PMC9387099 DOI: 10.1021/acs.langmuir.2c01708] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/27/2022] [Indexed: 06/10/2023]
Abstract
Superhydrophobic (SH) polylactic acid (PLA) surfaces were previously produced by various methods and used especially in biomedical applications and oil/water separation processes after 2008. However, the wettability of SH-PLA patterns containing micropillars has not been investigated before. In this study, PLA patterns having regular microstructured pillars with 12 different pillar diameters and pillar-to-pillar distances were prepared by hot pressing pre-flattened PLA sheets onto preformed polydimethylsiloxane (PDMS) soft molds having micro-sized pits. PDMS templates were previously prepared by photolithography using SU-8 molds. Apparent, advancing, and receding water contact angle measurements were carried out on the PLA patterns containing micropillars, and the morphology of the patterns was examined by optical and SEM microscopy. The largest contact angle obtained without the surface modification of the pure PLA pattern was 139°. Then, PLA micropatterns were hydrophobized using three types of silanes via chemical vapor deposition method, and SH-PLA patterns were obtained having θs of up to 167°. It was found that the highest θ values could be obtained when PLA pattern samples were coated with a silane containing a fluorine atom in its chemical structure. Washing and service life stability tests were also performed on the coated pattern samples and all of the silane coatings on the PLA patterns were found to be resistant over a 6 month period.
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Affiliation(s)
- Eda Hazal Tümer
- Department
of Chemical Engineering, Gebze Technical
University, Gebze, Kocaeli 41400, Türkiye
| | - H. Yildirim Erbil
- Department
of Chemical Engineering, Gebze Technical
University, Gebze, Kocaeli 41400, Türkiye
| | - Numan Akdoǧan
- Department
of Physics, Gebze Technical University, Gebze, Kocaeli 41400, Türkiye
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Astanei D, Burlica R, Cretu DE, Olariu M, Stoica I, Beniuga O. Treatment of Polymeric Films Used for Printed Electronic Circuits Using Ambient Air DBD Non-Thermal Plasma. MATERIALS (BASEL, SWITZERLAND) 2022; 15:1919. [PMID: 35269150 PMCID: PMC8911746 DOI: 10.3390/ma15051919] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/25/2022] [Accepted: 03/03/2022] [Indexed: 02/06/2023]
Abstract
This study aims to present the properties of the polymeric films after being subjected to DBD plasma treatment in atmospheric conditions. Three different commercial films of polyester (Xerox Inkjet transparencies and Autostat CUS5 Clear film) and polycarbonate (Lexan™ 8010 MC) have been considered for the tests. The surface wettability has been evaluated based on static water contact angle (WCA) for different treatment times varying between 0.2 s and 30 s, the results revealing a maximum WCA decrease compared to a pristine of up to 50% for Xerox films, 75% for Autostat and 70% for Lexan. The persistence of the hydrophilic effect induced by the plasma treatment has also been verified for up to 72 h of storage after treatment, the results indicating a degradation of the treatment effects starting with the first hours after the treatment. The WCA stabilizes to a value inferior to the one corresponding to pristine in the first 24 h after plasma treatment. The adhesion forces, as well as preliminary surface morphology evaluations have been determined for the considered films using atomic force microscopy (AFM). The adhesion forces are increased together with the prolongation of the plasma treatment application time, varying from initial values of 165 nN, 58 nN and 204 nN to around 390 nN, 160 nN and 375 nN for Xerox, Autostat and Lexan films, respectively, after 5 s of DBD treatment. For the considered materials, the results revealed that the plasma treatment determines morphological changes of the surfaces indicating an increase in surface roughness.
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Affiliation(s)
- Dragos Astanei
- Faculty of Electrical Engineering, “Gheorghe Asachi” Technical University of Iasi, 700050 Iaşi, Romania; (D.A.); (D.-E.C.); (M.O.); (O.B.)
| | - Radu Burlica
- Faculty of Electrical Engineering, “Gheorghe Asachi” Technical University of Iasi, 700050 Iaşi, Romania; (D.A.); (D.-E.C.); (M.O.); (O.B.)
| | - Daniel-Eusebiu Cretu
- Faculty of Electrical Engineering, “Gheorghe Asachi” Technical University of Iasi, 700050 Iaşi, Romania; (D.A.); (D.-E.C.); (M.O.); (O.B.)
| | - Marius Olariu
- Faculty of Electrical Engineering, “Gheorghe Asachi” Technical University of Iasi, 700050 Iaşi, Romania; (D.A.); (D.-E.C.); (M.O.); (O.B.)
- S.C. Prosupport Consulting S.R.L., 707410 Valea Lupului, Romania
| | - Iuliana Stoica
- Department of Physical Chemistry of Polymers, Petru Poni Institute of Macromolecular Chemistry, 700487 Iaşi, Romania;
| | - Oana Beniuga
- Faculty of Electrical Engineering, “Gheorghe Asachi” Technical University of Iasi, 700050 Iaşi, Romania; (D.A.); (D.-E.C.); (M.O.); (O.B.)
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9
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Erbil HY. Precursor film formation on catalyst–electrolyte–gas boundaries during CO 2 electroreduction with gas diffusion electrodes. Catal Sci Technol 2022. [DOI: 10.1039/d2cy01576e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thin and long layers of catholyte precursor films spread near triple-phase boundaries on composite catalysts containing hydrophobic materials. Dissolved CO2 molecules in the precursor films reduce on the composite catalyst surface without depletion.
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10
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Qiu J, Chen S, Di Y, Wang H, Lan L, Wang L. Prediction of Droplet Sliding on the Continuity of the Three-Phase Contact Line. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:13038-13045. [PMID: 34702036 DOI: 10.1021/acs.langmuir.1c02102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Many animals and plants have evolved wonderful hydrophobic abilities to adapt to the complex climate environment. The microstructure design of a superhydrophobic surface focuses on bionics and will be restricted by processing technology. Although certain functions can be achieved, there is a lack of unified conclusion on the wetting mechanism and a few quantitative analyses of the continuity of the three-phase contact line. Therefore, the relationship between the surface microstructure of the lattice pattern and the critical sliding angle of the water droplet in the Cassie state was investigated in this paper, and we proposed a method to quantitatively analyze the continuity of the three-phase contact line by a dimensionless length f. The results showed that the three-phase contact line was an important factor to determine the sliding performance of the droplet. The upward traction force generated by the surface tension through the force analysis on the three-phase contact line can enhance the sliding ability of the droplet on the solid surface. There was a good negative linear correlation between the critical sliding angle and dimensionless length, which provided a guiding basis for the optimal design of superhydrophobic surfaces.
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Affiliation(s)
- Junhong Qiu
- College of Mechanical and Electrical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China
| | - Shuang Chen
- College of Mechanical and Electrical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China
| | - Yuelan Di
- National Key Laboratory for Remanufacturing, Army Academy of Armored Forces, Beijing 100072, China
| | - Haidou Wang
- National Engineering Research Center for Remanufacturing, Army Academy of Armored Forces, Beijing 100072, China
| | - Ling Lan
- National Key Laboratory for Remanufacturing, Army Academy of Armored Forces, Beijing 100072, China
| | - Li Wang
- National Key Laboratory for Remanufacturing, Army Academy of Armored Forces, Beijing 100072, China
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Dexamethasone-Loaded Bioactive Coatings on Medical Grade Stainless Steel Promote Osteointegration. Pharmaceutics 2021; 13:pharmaceutics13040568. [PMID: 33923814 PMCID: PMC8073817 DOI: 10.3390/pharmaceutics13040568] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/06/2021] [Accepted: 04/13/2021] [Indexed: 11/22/2022] Open
Abstract
In this study, a multilayer bioactive coating based on carboxymethyl cellulose (CMC) and dexamethasone (DEX) was prepared on medical-grade stainless steel (AISI 316LVM). Its aim was the controlled drug delivery of the incorporated anti‑inflammatory drug, which at the same time promotes osteogenic differentiation of mesenchymal stem cells. Due to DEX’s limited solubility in physiological fluids, which limits the loading capacity of coatings, it was further combined with β-cyclodextrin to increase its concentration in the bioactive coating. Controlled release of DEX from the multilayer coating was achieved in four steps: a “burst”, i.e., very fast, release step (in an immersion interval of 0–10 min), a fast release step (10–30 min), a slow-release step (60–360 min), and a plateau step (360–4320 min), following a zero-order release or Higuchi model release mechanism. Successful layer-by-layer coating formation was confirmed using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). It was shown that the application of the coating significantly increases the hydrophilic character of AISI 316LVM, and also significantly increases the surface roughness, which is known to promote cell growth. In addition, electrochemical measurements demonstrated that the coating application does not increase the susceptibility of medical-grade stainless steel to corrosion. In vitro cell testing using all cell types with which such coatings come into contact in the body (osteoblasts, chondrocytes, and mesenchymal stem cells (MSCs)) showed very good biocompatibility towards all of the mentioned cells. It further confirmed that the coatings promoted MSCs osteogenic differentiation, which is the desired mode of action for orthopedic implants.
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