The Influence of Water Contact Angle on the Colonization of Diatoms (Navicula sp and Pinnularia sp) and Ulva Spores (Pertusa)

2013 ◽  
Vol 562-565 ◽  
pp. 1229-1233
Author(s):  
Jin Wei Zhang ◽  
Cun Guo Lin ◽  
Li Wang ◽  
Ji Yong Zheng ◽  
Feng Ling Xu
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Adhesive Force ◽  
Self Assembled Monolayers ◽  
Use Of Self ◽  
Water Contact ◽  
Force Increase ◽  
Assembled Monolayers ◽  
Influence Of Water ◽  
Proportional Relationship

The surface with different water contact angle (θAW) was prepared through the use of self-assembled monolayers (SAMs) and the effect of water contact angle on the colonization of diatoms (Naviculasp andPinnulariasp) andUlvaspores (Pertusa) was researched in an optional environment. Results revealed that the statistical adhesion density of colonized diatoms have a reciprocal-proportional relationship with θAW, and the adhesive force increase with the increase of θAW. However, it was the other way round forUlvaspores. Different with previous primary adhesion study, it also was revealed that diatoms have selectivity in colonization stage. All of these must due to their different reproduce (or grow) mode and extracellular polymers (EPS) composition.

Reconfigurable Hydrophobic/Hydrophilic Surfaces Based on Self-Assembled Monolayers

2003 ◽  
Vol 774 ◽  
Author(s):  
Joanne Deval ◽  
Teodoro A. Umali ◽  
Brandee L. Spencer ◽  
Esther H. Lan ◽  
Bruce Dunn ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Water ◽  
Water Contact Angle ◽  
Self Assembled Monolayers ◽  
Ionic Surfactant ◽  
Initial Surface ◽  
Lauryl Sulfate ◽  
Water Contact ◽  
Assembled Monolayers ◽  
Self Assembled

AbstractThe fabrication of micron-scale channels and reaction chambers using micromachining techniques has created devices with large surface to volume ratios. As a result, surface properties play a major role in determining the behavior of micromachined devices. In this work, we present strategies that can be used to reconfigure surfaces from hydrophobic to hydrophilic or from hydrophilic to hydrophobic. The reversible nature of the surface is made possible by using deposition and removal of biomolecules or amphiphiles on self-assembled monolayers (SAMs). When the initial surface was hydrophobic (using a CH3-terminated SAM on the surface, water contact angle ∼100), it was rendered hydrophilic (water contact angle ≤60°) using monolayer adsorption of avidin protein. To retrieve the hydrophobicity, the avidin was subsequently removed using non-ionic surfactant octyl-β-D-glucopyranoside. Moreover, by incorporating a biotinylated poly(ethyleneglycol), the avidin-coated surface was resistant to further non-specific adsorption. If the initial surface was hydrophilic (using a CO2H-terminated SAM on the surface, water contact angle ≤20°), it was rendered hydrophobic (water contact angle >90°) using monolayer amphiphilic octadecylamine adsorption. The hydrophilicity was restored after subsequently removing the amphiphile using anionic surfactant sodium lauryl sulfate. Both types of surfaces showed excellent reversibility and demonstrated the ability to control surface wettability.

scholarly journals Use of Self-Assembled Monolayers of Different Wettabilities To Study Surface Selection and Primary Adhesion Processes of Green Algal (Enteromorpha) Zoospores

2000 ◽  
Vol 66 (8) ◽  
pp. 3249-3254 ◽  
Author(s):  
Maureen E. Callow ◽  
J. A. Callow ◽  
Linnea K. Ista ◽  
Sarah E. Coleman ◽  
Aleece C. Nolasco ◽  
...  
Keyword(s):  
Contact Angle ◽  
Photoelectron Spectroscopy ◽  
Contact Angles ◽  
Self Assembled Monolayers ◽  
Use Of Self ◽  
Oh Groups ◽  
X Ray ◽  
Green Algal ◽  
Assembled Monolayers ◽  
Self Assembled

ABSTRACT We investigated surface selection and adhesion of motile zoospores of a green, macrofouling alga (Enteromorpha) to self-assembled monolayers (SAMs) having a range of wettabilities. The SAMs were formed from alkyl thiols terminated with methyl (CH3) or hydroxyl (OH) groups or mixtures of CH3- and OH-terminated alkyl thiols and were characterized by measuring the advancing contact angles and by X-ray photoelectron spectroscopy. There was a positive correlation between the number of spores that attached to the SAMs and increasing contact angle (hydrophobicity). Moreover, the sizes of the spore groups (adjacent spores touching) were larger on the hydrophobic SAMs. Video microscopy of a patterned arrangement of SAMs showed that more zoospores were engaged in swimming and “searching” above the hydrophobic sectors than above the hydrophilic sectors, suggesting that the cells were able to “sense” that the hydrophobic surfaces were more favorable for settlement. The results are discussed in relation to the attachment of microorganisms to substrata having different wettabilities.

A Facile All-Solution-Processed Surface with High Water Contact Angle and High Water Adhesive Force

2017 ◽  
Vol 9 (27) ◽  
pp. 23246-23254 ◽  
Author(s):  
Mei Chen ◽  
Wei Hu ◽  
Xiao Liang ◽  
Cheng Zou ◽  
Fasheng Li ◽  
...  
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
High Water ◽  
Adhesive Force ◽  
Water Contact ◽  
Solution Processed

Long-Term Stable Metal Organic Framework (MOF) Based Mixed Matrix Membranes for Ultrafiltration

2020 ◽  
Author(s):  
Muayad Al-shaeli ◽  
Stefan J. D. Smith ◽  
Shanxue Jiang ◽  
Huanting Wang ◽  
Kaisong Zhang ◽  
...  
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Mixed Matrix Membranes ◽  
Recovery Ratio ◽  
Mixed Matrix ◽  
Water Contact ◽  
Membrane Performance ◽  
Metal Organic ◽  
Matrix Membranes

<p>In this study, novel <a>mixed matrix polyethersulfone (PES) membranes</a> were synthesized by using two different kinds of metal organic frameworks (MOFs), namely UiO-66 and UiO-66-NH<sub>2</sub>. The composite membranes were characterised by SEM, EDX, FTIR, PXRD, water contact angle, porosity, pore size, etc. Membrane performance was investigated by water permeation flux, flux recovery ratio, fouling resistance and anti-fouling performance. The stability test was also conducted for the prepared mixed matrix membranes. A higher reduction in the water contact angle was observed after adding both MOFs to the PES and sulfonated PES membranes compared to pristine PES membranes. An enhancement in membrane performance was observed by embedding the MOF into PES membrane matrix, which may be attributed to the super-hydrophilic porous structure of UiO-66-NH<sub>2</sub> nanoparticles and hydrophilic structure of UiO-66 nanoparticles that could accelerate the exchange rate between solvent and non-solvent during the phase inversion process. By adding the MOFs into PES matrix, the flux recovery ratio was increased greatly (more than 99% for most mixed matrix membranes). The mixed matrix membranes showed higher resistance to protein adsorption compared to pristine PES membranes. After immersing the membranes in water for 3 months, 6 months and 12 months, both MOFs were stable and retained their structure. This study indicates that UiO-66 and UiO-66-NH<sub>2</sub> are great candidates for designing long-term stable mixed matrix membranes with higher anti-fouling performance.</p>

scholarly journals Surface modification of PMMA polymer and its composites with PC61BM fullerene derivative using an atmospheric pressure microwave argon plasma sheet

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Andrzej Sikora ◽  
Dariusz Czylkowski ◽  
Bartosz Hrycak ◽  
Magdalena Moczała-Dusanowska ◽  
Marcin Łapiński ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Modification ◽  
Chemical Composition ◽  
Water Contact Angle ◽  
Plasma Sheet ◽  
Atmospheric Pressure ◽  
Argon Plasma ◽  
Fullerene Derivative ◽  
Water Contact ◽  
Pmma Polymer

AbstractThis paper presents the results of experimental investigations of the plasma surface modification of a poly(methyl methacrylate) (PMMA) polymer and PMMA composites with a [6,6]-phenyl-C61-butyric acid methyl ester fullerene derivative (PC61BM). An atmospheric pressure microwave (2.45 GHz) argon plasma sheet was used. The experimental parameters were: an argon (Ar) flow rate (up to 20 NL/min), microwave power (up to 530 W), number of plasma scans (up to 3) and, the kind of treated material. In order to assess the plasma effect, the possible changes in the wettability, roughness, chemical composition, and mechanical properties of the plasma-treated samples’ surfaces were evaluated by water contact angle goniometry (WCA), atomic force microscopy (AFM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The best result concerning the water contact angle reduction was from 83° to 29.7° for the PMMA material. The ageing studies of the PMMA plasma-modified surface showed long term (100 h) improved wettability. As a result of plasma treating, changes in the samples surface roughness parameters were observed, however their dependence on the number of plasma scans is irregular. The ATR-FTIR spectra of the PMMA plasma-treated surfaces showed only slight changes in comparison with the spectra of an untreated sample. The more significant differences were demonstrated by XPS measurements indicating the surface chemical composition changes after plasma treatment and revealing the oxygen to carbon ratio increase from 0.1 to 0.4.

scholarly journals Physicochemical Properties and Biocompatibility of Electrospun Polycaprolactone/Gelatin Nanofibers

2021 ◽  
Vol 18 (9) ◽  
pp. 4764
Author(s):  
Wei Lee Lim ◽  
Shiplu Roy Chowdhury ◽  
Min Hwei Ng ◽  
Jia Xian Law
Keyword(s):  
Contact Angle ◽  
Physicochemical Properties ◽  
Water Contact Angle ◽  
Ligament Injury ◽  
Great Promise ◽  
Composition Analysis ◽  
Water Contact ◽  
Tenogenic Differentiation ◽  
Good Biocompatibility ◽  
Tissue Grafts

Tissue-engineered substitutes have shown great promise as a potential replacement for current tissue grafts to treat tendon/ligament injury. Herein, we have fabricated aligned polycaprolactone (PCL) and gelatin (GT) nanofibers and further evaluated their physicochemical properties and biocompatibility. PCL and GT were mixed at a ratio of 100:0, 70:30, 50:50, 30:70, 0:100, and electrospun to generate aligned nanofibers. The PCL/GT nanofibers were assessed to determine the diameter, alignment, water contact angle, degradation, and surface chemical analysis. The effects on cells were evaluated through Wharton’s jelly-derived mesenchymal stem cell (WJ-MSC) viability, alignment and tenogenic differentiation. The PCL/GT nanofibers were aligned and had a mean fiber diameter within 200–800 nm. Increasing the GT concentration reduced the water contact angle of the nanofibers. GT nanofibers alone degraded fastest, observed only within 2 days. Chemical composition analysis confirmed the presence of PCL and GT in the nanofibers. The WJ-MSCs were aligned and remained viable after 7 days with the PCL/GT nanofibers. Additionally, the PCL/GT nanofibers supported tenogenic differentiation of WJ-MSCs. The fabricated PCL/GT nanofibers have a diameter that closely resembles the native tissue’s collagen fibrils and have good biocompatibility. Thus, our study demonstrated the suitability of PCL/GT nanofibers for tendon/ligament tissue engineering applications.

Osteoconductivity of Superhydrophilic Ti- and Zr-Alloy for Biomedical Application

2016 ◽  
Vol 879 ◽  
pp. 2524-2527
Author(s):  
Masazumi Okido ◽  
Kensuke Kuroda
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Strong Influence ◽  
Biomedical Application ◽  
Hydrophobic Surface ◽  
Hydrophilic Surface ◽  
Water Contact ◽  
Zr Alloy ◽  
Zr Alloys

Surface hydrophilicity is considered to have a strong influence on the biological reactions of bone-substituting materials. However, the influence of a hydrophilic or hydrophobic surface on the osteoconductivity is not completely clear. In this study, we produced super-hydrophilic and hydrophobic surface on Ti-and Zr-alloys. Hydrothermal treatment at 180 oC for 180 min. in the distilled water and immersion in x5 PBS(-) brought the super-hydrophilic surface (water contact angle < 10 (deg.)) and heat treatment of as-hydrothermaled the hydrophobic surface. The osteoconductivity of the surface treated samples with several water contact angle was evaluated by in vivo testing. The surface properties, especially water contact angle, strongly affected the osteoconductivity and protein adsorbability, and not the surface substance.

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

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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