Bacteria Death and Osteoblast Metabolic Activity Correlated to Hydrothermally Synthesised TiO2 Surface Properties

Orthopaedic surgery comes with an inherent risk of bacterial infection, prolonged antibiotic therapy and revision surgery. Recent research has focused on nanostructured surfaces to improve the bactericidal and osseointegrational properties of implants. However, an understanding of the mechanical properties of bactericidal materials is lacking. In this work, the surface properties of hydrothermal TiO2 nanostructured surfaces are investigated for their effect on bactericidal efficiency and cellular metabolic activity of human osteoblast cells. TiO2 nanostructures, approximately 307 nm in height and 14 GPa stiffness, were the most effective structures against both gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa) bacteria. Statistical analysis significantly correlated structure height to the death of both bacteria strains. In addition, the surface contact angle and Young’s modulus were correlated to osteoblast metabolic activity. Hydrophilic surfaces with a contact angle between 35 and 50° produced the highest cellular metabolic activity rates after 24 hours of incubation. The mechanical tests showed that nanostructures retain their mechanical stability and integrity over a long time-period, reaffirming the surfaces’ applicability for implants. This work provides a thorough examination of the surface, mechanical and wettability properties of multifunctional hydrothermally synthesised nanostructured materials, capable of killing bacteria whilst improving osteoblast metabolic rates, leading to improved osseointegration and antibacterial properties of orthopaedic implants.

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Antibacterial Properties of Plasma-Activated Perfluorinated Substrates with Silver Nanoclusters Deposition

Nanomaterials ◽

10.3390/nano11010182 ◽

2021 ◽

Vol 11 (1) ◽

pp. 182

Author(s):

Petr Slepička ◽

Silvie Rimpelová ◽

Nikola Slepičková Kasálková ◽

Dominik Fajstavr ◽

Petr Sajdl ◽

...

Keyword(s):

Surface Properties ◽

Antibacterial Properties ◽

Argon Plasma ◽

Antimicrobial Effect ◽

Silver Nanoclusters ◽

Plasma Modification ◽

Material Surface ◽

Silver Deposition ◽

Force Microscopy ◽

Atomic Force

This article is focused on the evaluation of surface properties of polytetrafluoroethylene (PTFE) nanotextile and a tetrafluoroethylene-perfluoro(alkoxy vinyl ether) (PFA) film and their surface activation with argon plasma treatment followed with silver nanoclusters deposition. Samples were subjected to plasma modification for a different time exposure, silver deposition for different time periods, or their combination. As an alternative approach, the foils were coated with poly-L-lactic acid (PLLA) and silver. The following methods were used to study the surface properties of the polymers: goniometry, atomic force microscopy, and X-ray photoelectron microscopy. By combining the aforementioned methods for material surface modification, substrates with antibacterial properties eliminating the growth of Gram-positive and Gram-negative bacteria were prepared. Studies of antimicrobial activity showed that PTFE plasma-modified samples coated with PLLA and deposited with a thin layer of Ag had a strong antimicrobial effect, which was also observed for the PFA material against the bacterial strain of S. aureus. Significant antibacterial effect against S. aureus, Proteus sp. and E. coli has been demonstrated on PTFE nanotextile plasma-treated for 240 s, coated with PLLA, and subsequently sputtered with thin Ag layer.

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SrTiO3 Functional Ceramics Thin Film Prepared by Self-Assembled Monolayers with the Liquid Phase Deposition Method on Silicon Substrates

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.105-106.270 ◽

2010 ◽

Vol 105-106 ◽

pp. 270-273

Author(s):

Hui Jun Ren ◽

Guo Qiang Tan ◽

Hong Yan Miao ◽

Ya Yu Song ◽

Ao Xia

Keyword(s):

Thin Film ◽

Contact Angle ◽

Liquid Phase ◽

Deposition Temperature ◽

Precursor Solution ◽

Self Assembled Monolayers ◽

Silicon Substrates ◽

Liquid Phase Deposition ◽

Assembled Monolayers ◽

Surface Contact Angle

In this article, (NH4)2TiF6, SrNO3 and H3BO3 were used as raw materials to prepare the precursor solution with the ratio of AHFT/SN/BA=1:1:3. The thin films of SrTiO3 were fabricated on the functional silicon substrates (100) by self-assembled monolayers (SAMs) with the liquid phase deposition (LPD). This article also studied the effects of wet state and the deposition temperature of the precursor solution before and after the functionalization of silicon substrate on the thin film growth. The results indicated that after the immersion in OTS for 30min, the surface contact angle of the silicon substrate changed from 24.64° to 100.91°. The substrate appeared hydrophobic property and it was irradiated by UV light for 30min. Then the surface contact angle of the substrate decreased to 5.00°. The substrate appeared hydrophilicity. The concentration of the precursor solution was 0.025 mol/L, the deposition temperature was 40°C and the deposition time was 9h, which were all helpful to SrTiO3 crystallization. XRD and SEM were used to characterize the physical phase of thin film and surface morphology at 600 °C with annealing and heat retaining for 2h. The results indicated that the thin film prepared by the mono-crystal Si substrate was SrTiO3 thin film with better crystalline. On the crystal surfaces of (110), (100), (200) and (211), there appeared the obvious diffraction peaks. The SrTiO3 grains on the surface had the clear outline and were regular and long columnar crystals.

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Magnetically Induced Decrease in Droplet Contact Angle on Nanostructured Surfaces

Langmuir ◽

10.1021/la2024633 ◽

2011 ◽

Vol 27 (19) ◽

pp. 11747-11751 ◽

Cited By ~ 25

Author(s):

Qian Zhou ◽

William D. Ristenpart ◽

Pieter Stroeve

Keyword(s):

Contact Angle ◽

Nanostructured Surfaces

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Increasing Storage Modulus, Contact Angle and Surface Tension of Airway Mucus Increases Clearance by Simulated Cough Through a Model Trachea

ASME 2010 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2010-19703 ◽

2010 ◽

Author(s):

Anpalaki J. Ragavan ◽

Cahit A. Evrensel ◽

Peter Krumpe

Keyword(s):

Surface Tension ◽

Contact Angle ◽

Storage Modulus ◽

Surface Properties ◽

Respiratory Diseases ◽

Interactive Effects ◽

Altered Surface ◽

Human Trachea ◽

Tension Increase ◽

And Storage

Altered surface and viscoelastic material properties of mucus during respiratory diseases have a strong influence on its clearance by cilia and cough. Combined effects of the surface properties (contact angle and surface tension) and storage modulus with relatively unchanged viscosity on displacement of the simulated mucus aliquot during simulated cough through a model adult human trachea is investigated. For the mucus simulants used in this study contact angle and surface tension increase significantly as storage modulus increase while viscosity remains practically unchanged. Displacement of mucus simulant aliquots increased significantly with increasing storage modulus (and contact angle) at a given cough velocity in the range between 5 meters/second (m/s) and 30 m/s with duration 0.3 s. Results suggest that the interactive effects of elasticity and surface properties may help facilitate mucus displacement at low cough velocities.

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Effect of low-temperature plasma treatment and γ-irradiation on the surface properties of thin films based on polylactic acid

Physics and Chemistry of Materials Treatment ◽

10.30791/0015-3214-2020-6-40-55 ◽

2020 ◽

Vol 6 ◽

pp. 40-55

Author(s):

N.M. Ivanova ◽

◽

E.O. Filippova ◽

A.N. Aleinik ◽

V.F. Pichugin ◽

...

Keyword(s):

Thin Films ◽

Contact Angle ◽

Low Temperature ◽

Polylactic Acid ◽

Surface Properties ◽

Polar Component ◽

Low Temperature Plasma ◽

Plasma Exposure ◽

Γ Irradiation ◽

Temperature Plasma

Effects of the low-temperature plasma exposure, γ-irradiation, and joint g-irradiation and plasma exposure on the structure and surface properties of thin films based on polylactic acid (PLA) have been investigated. Films were obtained by the method a solvent-casting. It has been shown that films based on polylactic acid have topographically different sides: a smoother inner side and embossed outer one. PLA films have properties close to those hydrophobic, with a contact angle in the range of 70°-73° regardless of the surface side and belong to a weakly polar materials. The combined effect of plasma and gamma radiation slightly changes the surface topography. The effect of low-temperature plasma on the surface of the films leads to a decrease in the contact angle by 13°-55° (9-11%) and an increase in surface energy due to the polar component. The results of in vivo experiments on rabbits are presented. Biomicroscopy, optical coherence tomography, morphological and electron microscopic examination of the cornea after implantation of initial and radiation and plasma treated films showed that implantation of the films in the anterior chamber is not accompanied by a pronounced inflammatory reaction and increased intraocular pressure, while maintaining the morphological structure of the cornea almost unchanged.

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Alternate AChE-R variants facilitate cellular metabolic activity and resistance to genotoxic stress through enolase and RACK1 interactions

Chemico-Biological Interactions ◽

10.1016/j.cbi.2008.05.019 ◽

2008 ◽

Vol 175 (1-3) ◽

pp. 11-21 ◽

Cited By ~ 14

Author(s):

Inbal Mor ◽

Tal Bruck ◽

David Greenberg ◽

Amit Berson ◽

Leticia Schreiber ◽

...

Keyword(s):

Metabolic Activity ◽

Genotoxic Stress ◽

Cellular Metabolic Activity

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Regional Gas Exchange and Cellular Metabolic Activity in Ventilator-induced Lung Injury

Anesthesiology ◽

10.1097/01.anes.0000264748.86145.ac ◽

2007 ◽

Vol 106 (4) ◽

pp. 723-735 ◽

Cited By ~ 56

Author(s):

Guido Musch ◽

Jose G. Venegas ◽

Giacomo Bellani ◽

Tilo Winkler ◽

Tobias Schroeder ◽

...

Keyword(s):

Gas Exchange ◽

Lung Injury ◽

Metabolic Activity ◽

Cell Activation ◽

Test Lung ◽

Ventilator Induced Lung Injury ◽

Positron Emission ◽

Cellular Metabolic Activity ◽

The Right ◽

Tissue Fraction

Background Alveolar overdistension and repetitive derecruitment-recruitment contribute to ventilator-induced lung injury (VILI). The authors investigated (1) whether inflammatory cell activation due to VILI was assessable by positron emission tomography and (2) whether cell activation due to dynamic overdistension alone was detectable when other manifestations of VILI were not yet evident. Methods The authors assessed cellular metabolic activity with [(18)F]fluorodeoxyglucose and regional gas exchange with [(13)N]nitrogen. In 12 sheep, the left ("test") lung was overdistended with end-inspiratory pressure of 50 cm H(2)O for 90 min, while end-expiratory derecruitment of this lung was either promoted with end-expiratory pressure of -10 cm H(2)O in 6 of these sheep (negative end-expiratory pressure [NEEP] group) or prevented with +10 cm H(2)O in the other 6 (positive end-expiratory pressure [PEEP] group) to isolate the effect of overdistension. The right ("control") lung was protected from VILI. Results Aeration decreased and shunt fraction increased in the test lung of the NEEP group. [(18)F]fluorodeoxyglucose uptake of this lung was higher than that of the control lung and of the test lung of the PEEP group, and correlated with neutrophil count. When normalized by tissue fraction to account for increased aeration of the test lung in the PEEP group, [(18)F]fluorodeoxyglucose uptake was elevated also in this group, despite the fact that gas exchange had not yet deteriorated after 90 min of overdistension alone. Conclusion The authors could detect regional neutrophil activation in VILI even when end-expiratory derecruitment was prevented and impairment of gas exchange was not evident. Concomitant end-expiratory derecruitment converted this activation into profound inflammation with decreased aeration and regional shunting.

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Comparison of Linear Poly Ethylene Imine (LPEI) and Poly L-Lysine (PLL) in Fabrication of CHOK1 Cell-Loaded Multilayer Alginate Microcapsules

Advanced Pharmaceutical Bulletin ◽

10.34172/apb.2020.035 ◽

2020 ◽

Vol 10 (2) ◽

pp. 290-296

Author(s):

Fariba Hajifathaliha ◽

Arash Mahboubi ◽

Elham Mohit ◽

Noushin Bolourchian ◽

Vahid Khalaj ◽

...

Keyword(s):

Cell Viability ◽

Cell Survival ◽

Metabolic Activity ◽

Encapsulation Efficiency ◽

Cell Encapsulation ◽

High Price ◽

Ethylene Imine ◽

Linear Poly ◽

Cellular Metabolic Activity ◽

Poly Ethylene

Purpose: Poly l-lysine (PLL) has been introduced as a strengthening covering layer for alginate microcapsules which are the most convenient way for cell encapsulation. Some disadvantages of PLL such as high price and low biocompatibility have prompted scientists to find better alternatives. Linear poly ethylene imine (LPEI), thanks to its highly similar structure to PLL, could be considered as a proper cost-effective alternative. In this study LPEI and PLL were compared as covering layers of cell-loaded alginate-LPEI-alginate (cALA) and alginate-PLL-alginate (cAPA) microcapsules. Methods: In addition to the physico-mechanical properties, the encapsulation efficiency, cell survival post encapsulation, cell viability, and cellular metabolic activity within the microcapsules were evaluated using trypan blue, live/dead cell staining, and MTT test, respectively. Results: Physico-mechanical evaluation of the microcapsules revealed that the cell microencapsulation process did not affect their shape, size, and mechanical stability. Although the encapsulation efficiency for cALA and cAPA was not different (P>0.05), cell survival post encapsulation was higher in cALA than in cAPA (P<0.05) which could be the reason for the higher cell viability and also cellular metabolic activity within these microcapsules in comparison to cAPA. Conclusion: Here, based on these results, ALA could be introduced as a preferable alternative to APA for cell encapsulation.

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Development of an antimicrobial peptide-loaded mineralized collagen bone scaffold for infective bone defect repair

Regenerative Biomaterials ◽

10.1093/rb/rbaa015 ◽

2020 ◽

Vol 7 (5) ◽

pp. 515-525

Author(s):

Yuzhu He ◽

Yahui Jin ◽

Xiaoxia Ying ◽

Qiong Wu ◽

Shenglian Yao ◽

...

Keyword(s):

Antibacterial Properties ◽

Clinical Work ◽

Bone Defects ◽

Mechanical Tests ◽

Great Promise ◽

Plga Microspheres ◽

Bone Scaffold ◽

Defect Repair ◽

Mineralized Collagen

Abstract The repair of infective bone defects is a great challenge in clinical work. It is of vital importance to develop a kind of bone scaffold with good osteogenic properties and long-term antibacterial activity for local anti-infection and bone regeneration. A porous mineralized collagen (MC) scaffold containing poly(d,l-lactide-co-glycolic acid) (PLGA) microspheres loaded with two antibacterial synthetic peptides, Pac-525 or KSL-W was developed and characterized via scanning electron microscopy (SEM), porosity measurement, swelling and mechanical tests. The results showed that the MC scaffold embedded with smooth and compact PLGA microspheres had a positive effect on cell growth and also had antibacterial properties. Through toxicity analysis, cell morphology and proliferation analysis and alkaline phosphatase evaluation, the antibacterial scaffolds showed excellent biocompatibility and osteogenic activity. The antibacterial property evaluated with Staphylococcus aureus and Escherichia coli suggested that the sustained release of Pac-525 or KSL-W from the scaffolds could inhibit the bacterial growth aforementioned in the long term. Our results suggest that the antimicrobial peptides-loaded MC bone scaffold has good antibacterial and osteogenic activities, thus providing a great promise for the treatment of infective bone defects.

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Preparation of the Hybrids of Hydrotalcites and Chitosan by Urea Method and Their Antimicrobial Activities

Polymers ◽

10.3390/polym11101588 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1588 ◽

Cited By ~ 4

Author(s):

Bi Foua Claude Alain Gohi ◽

Hong-Yan Zeng ◽

Xiao-Ju Cao ◽

Kai-Min Zou ◽

Wenlin Shuai ◽

...

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Surface Properties ◽

Antimicrobial Agents ◽

Materials Science ◽

Mechanical Stability ◽

Antimicrobial Activities ◽

Molar Ratio ◽

Penicillium Cyclopium ◽

Urea Method

Hybrid nano-supra molecular structured materials can boost the functionality of nano- or supra-molecular materials by providing increased reactivity and conductivity, or by simply improving their mechanical stability. Herein, the studies in materials science exploring hybrid systems are investigated from the perspective of two important related applications: healthcare and food safety. Interfacing phase strategy was applied, and ZnAl layered double hydroxide-chitosan hybrids, prepared by the urea method (U-LDH/CS), were successfully synthesized under the conditions of different chitosan(CS) concentrations with a Zn/Al molar ratio of 5.0. The structure and surface properties of the U-LDH/CS hybrids were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectrometer(FTIR), scanning electronmicroscopy (SEM), ultravioletvisible (UV-Vis), and zero point charge (ZPC) techniques, where the effect of CS concentration on the structure and surface properties was investigated. The use of the U-LDH/CS hybrids as antimicrobial agents against Escherichia coli, Staphylococcus aureus, and Penicillium cyclopium was investigated in order to clarify the relationship between microstructure and antimicrobial ability. The hybrid prepared in a CS concentration of 1.0 g∙L−1 (U-LDH/CS1) exhibited the best antimicrobial activity and exhibited average inhibition zones of 24.2, 30.4, and 22.3mm against Escherichia coli, Staphylococcus aureus, and Penicillium cyclopium, respectively. The results showed that the appropriate addition of CS molecules could increase antimicrobial ability against microorganisms.

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