Biointerphases最新文献

{"title":"Composition controls soft hydrogel surface layer dimensions and contact mechanics.","authors":"Christopher L Johnson,&nbsp;Alison C Dunn","doi":"10.1116/6.0002047","DOIUrl":"https://doi.org/10.1116/6.0002047","url":null,"abstract":"<p><p>Hydrogels are soft hydrated polymer networks that are widely used in research and industry due to their favorable properties and similarity to biological tissues. However, it has long been difficult to create a hydrogel emulating the heterogeneous structure of special tissues, such as cartilage. One potential avenue to develop a structural variation in a hydrogel is the \"mold effect,\" which has only recently been discovered to be caused by absorbed oxygen within the mold surface interfering with the polymerization. This induces a dilute gradient-density surface layer with altered properties. However, the precise structure of the gradient-surface layer and its contact response have not yet been characterized. Such knowledge would prove useful for designs of composite hydrogels with altered surface characteristics. To fully characterize the hydrogel gradient-surface layer, we created five hydrogel compositions of varying monomer and cross-linker content to encompass variations in the layer. Then, we used particle exclusion microscopy during indentation and creep experiments to probe the contact response of the gradient layer of each composition. These experiments showed that the dilute structure of the gradient layer follows evolving contact behavior allowing poroelastic squeeze-out at miniscule pressures. Stiffer compositions had thinner gradient layers. This knowledge can potentially be used to create hydrogels with a stiff load-bearing bulk with altered surface characteristics tailored for specific tribological applications.</p>","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40460223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gold nanoparticle design for RNA compaction.","authors":"Jessica A Nash,&nbsp;Matthew D Manning,&nbsp;Alexey V Gulyuk,&nbsp;Aleksey E Kuznetsov,&nbsp;Yaroslava G Yingling","doi":"10.1116/6.0002043","DOIUrl":"https://doi.org/10.1116/6.0002043","url":null,"abstract":"<p><p>RNA-based therapeutics hold a great promise in treating a variety of diseases. However, double-stranded RNAs (dsRNAs) are inherently unstable, highly charged, and stiff macromolecules that require a delivery vehicle. Cationic ligand functionalized gold nanoparticles (AuNPs) are able to compact nucleic acids and assist in RNA delivery. Here, we use large-scale all-atom molecular dynamics simulations to show that correlations between ligand length, metal core size, and ligand excess free volume control the ability of nanoparticles to bend dsRNA far below its persistence length. The analysis of ammonium binding sites showed that longer ligands that bind deep within the major groove did not cause bending. By limiting ligand length and, thus, excess free volume, we have designed nanoparticles with controlled internal binding to RNA's major groove. NPs that are able to induce RNA bending cause a periodic variation in RNA's major groove width. Density functional theory studies on smaller models support large-scale simulations. Our results are expected to have significant implications in packaging of nucleic acids for their applications in nanotechnology and gene delivery.</p>","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40442662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mussel adhesion: A fundamental perspective on factors governing strong underwater adhesion.","authors":"Laura L E Mears,&nbsp;Julia Appenroth,&nbsp;Hui Yuan,&nbsp;Alper T Celebi,&nbsp;Pierluigi Bilotto,&nbsp;Alexander M Imre,&nbsp;Bruno Zappone,&nbsp;Rongxin Su,&nbsp;Markus Valtiner","doi":"10.1116/6.0002051","DOIUrl":"https://doi.org/10.1116/6.0002051","url":null,"abstract":"<p><p>Protein-based underwater adhesives of marine organisms exhibit extraordinary binding strength in high salinity based on utilizing a variety of molecular interaction mechanisms. These include acid-base interactions, bidentate bindings or complex hydrogen bonding interactions, and electrochemical manipulation of interfacial bonding. In this Perspective, we briefly review recent progress in the field, and we discuss how interfacial electrochemistry can vary interfacial forces by concerted tuning of surface charging, hydration forces, and tuning of the interfacial ion concentration. We further discuss open questions, controversial findings, and new paths into understanding and utilizing redox-proteins and derived polymers for enhancing underwater adhesion in a complex salt environment.</p>","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40439600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Construction strategies and the development trend of antibacterial surfaces.","authors":"Haixia Wu,&nbsp;Wei Liu,&nbsp;Caixia Liu,&nbsp;Can Ai","doi":"10.1116/6.0002147","DOIUrl":"https://doi.org/10.1116/6.0002147","url":null,"abstract":"<p><p>The construction of antibacterial surfaces is an efficient way to respond to the problem of microbial contamination. In this review, we first describe the formation process and characteristics of microbial contamination and the current research status of antibacterial surfaces. Then, the passive antiadhesion, active killing, and combination construction strategies of the antibacterial surface are discussed in detail. Based on different antibacterial mechanisms and existing problems of current antibacterial strategies, we then discuss the future development trends of the next generation of antibacterial surfaces.</p>","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40439601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D cell/scaffold model based on aligned-electrospun-nanofiber film/hydrogel multilayers for construction of anisotropic engineered tissue.","authors":"Jing-Yi Zhang,&nbsp;Nihad Cheraga,&nbsp;Ning-Ping Huang","doi":"10.1116/6.0002058","DOIUrl":"https://doi.org/10.1116/6.0002058","url":null,"abstract":"<p><p>Many tissues have a three-dimensional (3D) anisotropic structure compatible with their physiological functions. Engineering an in vitro 3D tissue having the natural structure and functions is a hotspot in tissue engineering with application for tissue regeneration, drug screening, and disease modeling. Despite various designs that have successfully guided the cellular alignment, only a few of them could precisely control the orientation of each layer in a multilayered construct or achieve adequate cell contact between layers. This study proposed a design of a multilayered 3D cell/scaffold model, that is, the cell-loaded aligned nanofiber film/hydrogel (ANF/Gel) model. The characterizations of the 3D cell-loaded ANF/Gel model in terms of design, construction, morphology, and cell behavior were systematically studied. The ANF was produced by efficiently aligned electrospinning using a self-designed, fast-and-easy collector, which was designed based on the parallel electrodes and modified with a larger gap area up to about 100 cm². The nanofibers generated by this simple device presented numerous features like high orientation, uniformity in fiber diameter, and thinness. The ANF/Gel-based cell/scaffold model was formed by encapsulating cell-loaded multilayered poly(lactic-co-glycolic acid)-ANFs in hydrogel. Cells within the ANF/Gel model showed high viability and displayed aligned orientation and elongation in accordance with the nanofiber orientation in each film, forming a multilayered tissue having a layer spacing of 60 μm. This study provides a multilayered 3D cell/scaffold model for the in vitro construction of anisotropic engineered tissues, exhibiting potential applications in cardiac tissue engineering.</p>","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10416333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vibrational sum frequency spectroscopy of thin film interfaces.","authors":"Erin G Moloney,&nbsp;Md S Azam,&nbsp;Canyu Cai,&nbsp;Dennis K Hore","doi":"10.1116/6.0002085","DOIUrl":"https://doi.org/10.1116/6.0002085","url":null,"abstract":"<p><p>We describe a basic theoretical treatment of how film-substrate and substrate-environment (air, water, and solution) interfaces can be selectively probed by controlling the film thickness and beam angles in a visible-infrared sum frequency generation experiment. In this model, we also account for the unique interfacial environment that may have optical properties that differ from the adjacent bulk phases. We see that this affects components of the electric field that are perpendicular to the surface such as when p-polarized light is used. We then provide an example using the glass-polydimethylsiloxane-air system and model the fields at both surfaces of the polymer. This is followed by some practical considerations for setting up such experiments and some typical experimental results.</p>","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33478682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tutorials in vibrational sum frequency generation spectroscopy. III. Collecting, processing, and analyzing vibrational sum frequency generation spectra.","authors":"James D Pickering,&nbsp;Mikkel Bregnhøj,&nbsp;Mette H Rasmussen,&nbsp;Kris Strunge,&nbsp;Tobias Weidner","doi":"10.1116/6.0001951","DOIUrl":"https://doi.org/10.1116/6.0001951","url":null,"abstract":"<p><p>In this Tutorial series, we aim to provide an accessible introduction to vibrational sum frequency generation (VSFG) spectroscopy, targeted toward people entering the VSFG world without a rigorous formal background in optical physics or nonlinear spectroscopy. In this article, we discuss in detail the processes of collecting and processing VSFG data, and user-friendly processing software (sfgtools) is provided for use by people new to the field. Some discussion of analyzing VSFG spectra is also given, specifically with a discussion of fitting homodyne VSFG spectra, and a discussion of what can be learned (both qualitatively and quantitatively) from VSFG spectra.</p>","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40587713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New antimicrobial peptide-antibiotic combination strategy for Pseudomonas aeruginosa inactivation.","authors":"Wenxu Han,&nbsp;Ziqi Wei,&nbsp;Terri A Camesano","doi":"10.1116/6.0001981","DOIUrl":"https://doi.org/10.1116/6.0001981","url":null,"abstract":"<p><p>Novel antimicrobials or new treatment strategies are urgently needed to treat Pseudomonas aeruginosa (P. aeruginosa) related infections and especially to address the problem of antibiotic resistance. We propose a novel strategy that combines the human antimicrobial peptide (AMP) LL37 with different antibiotics to find synergistic AMP-antibiotic combinations against P. aeruginosa strains in vitro. Our results showed that LL37 exhibited synergistic inhibitory and bactericidal effects against P. aeruginosa strains PAO1 and PA103 when combined with the antibiotics vancomycin, azithromycin, polymyxin B, and colistin. In addition, LL37 caused strong outer membrane permeabilization, as demonstrated through measurement of an increased uptake of the fluorescent probe N-phenyl-1-naphthylamine. The membrane permeabilization effects appear to explain why it was easier to rescue the effectiveness of the antibiotic toward the bacteria because the outer membrane of P. aeruginosa exhibits barrier function for antibiotics. Furthermore, the change in the zeta potential was measured for P. aeruginosa strains with the addition of LL37. Zeta potentials for P. aeruginosa strains PAO1 and PA103 were -40.9 and -10.9 mV, respectively. With the addition of LL37, negative zeta potentials were gradually neutralized. We found that positively charged LL37 can interact with and neutralize the negatively charged bacterial outer membrane through electrostatic interactions, and the process of neutralization is believed to have contributed to the increase in outer membrane permeability. Finally, to further illustrate the relationship between outer membrane permeabilization and the uptake of antibiotics, we used LL37 to make the outer membrane of P. aeruginosa strains more permeable, and minimum inhibitory concentrations (MICs) for several antibiotics (colistin, gentamicin, polymyxin B, vancomycin, and azithromycin) were measured. The MICs decreased were twofold to fourfold, in general. For example, the MICs of azithromycin and vancomycin decreased more than fourfold when against P. aeruginosa strain PAO1, which were the greatest decrease of any of the antibiotics tested in this experiment. As for PA103, the MIC of polymyxin B2 decreased fourfold, which was the strongest decrease seen for any of the antibiotics tested in this experiment. The increased uptake of antibiotics not only demonstrates the barrier role of the outer membrane but also validates the mechanism of synergistic effects that we have proposed. These results indicate the great potential of an LL37-antibiotic combination strategy and provide possible explanations for the mechanisms behind this synergy.</p>","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10442099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructural, mechanical, and in vitro corrosion properties of biodegradable Mg-Ag alloys.","authors":"Levent Elen,&nbsp;Yunus Turen,&nbsp;Hayrettin Ahlatci,&nbsp;Mehmet Unal,&nbsp;Deniz Ergin","doi":"10.1116/6.0001858","DOIUrl":"https://doi.org/10.1116/6.0001858","url":null,"abstract":"<p><p>In this study, casting, extrusion, biocorrosion, and corrosive wear properties of 0.5 wt. % (Zn, Ca, and Nd) element added Mg-3 wt. % Ag alloys were investigated. According to the test results, it was observed that the grain refinement occurred with the effect of Zn and Ca element additions in the as-cast alloys and thus some mechanical properties of the alloys improved. Similarly, the extrusion process provided grain refinement and improved mechanical properties. As a result of in vitro corrosion tests, similar results were also obtained in the as-cast alloys, while this situation became more apparent in the extruded alloys and exhibited more homogeneous corrosion properties. In the corrosive wear tests, the wear rate of the extruded alloys generally showed a decreasing trend. However, both the as-cast and extruded Mg-3 wt. %Ag-0.5 wt. % Ca alloys exhibited the lowest wear rate.</p>","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40575804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Titanium alkalinization improves response of osteoblasts to zoledronic acid.","authors":"Rodrigo Paes Vila Real, T. N. Pansani, L. M. Cardoso, C. A. de Souza Costa, F. G. Basso","doi":"10.1116/6.0001670","DOIUrl":"https://doi.org/10.1116/6.0001670","url":null,"abstract":"This investigation is aimed to determine the effect of the modification of titanium surface with NaOH on the metabolism of osteoblasts treated with zoledronic acid (ZA). Machined and NaOH-treated titanium disks were used. Surfaces were characterized by scanning electron microscopy, confocal microscopy, and x-ray photoelectron spectroscopy (XPS) analysis. Human osteoblasts were seeded onto the disks. After 24 h, cells were treated with ZA at 5 μM for 7 days. At this point, cell viability, collagen synthesis, total protein production, alkaline phosphatase activity, and mineral nodule deposition were assessed. The results of surface roughness were descriptively and statistically analyzed (t-Student), while the XPS results were qualitatively described. Cell metabolism data were analyzed by the analysis of variance two-way and Tukey tests at a 5% significance level. The results demonstrated that NaOH-treatment increased surface roughness (p < .05) and confirmed the presence of sodium titanate and a pH switch on the NaOH-treated disks. This modification also resulted in higher cell viability, collagen synthesis, total protein production, and alkaline phosphatase by osteoblasts when compared to cells seeded onto machined disks (p < 0.05). In the presence of ZA, all cellular metabolism and differentiation parameters were significantly reduced for cells seeded on both surfaces (p < 0.05); however, the cells seeded onto modified surfaces showed higher values for these parameters, except for mineral nodule deposition (p < 0.05). NaOH modification improved cell adhesion and metabolism of osteogenic cells even in the presence of ZA. The surface modification of titanium with NaOH solution may be an interesting strategy to improve metabolism and differentiation of osteoblasts and accelerate osseointegration process, mainly for tissues exposed to ZA.","PeriodicalId":9053,"journal":{"name":"Biointerphases","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41416431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}