Beyond biomimicry – next generation applications of bioinspired adhesives from microfluidics to composites

• Dan Sameoto

Beilstein J. Nanotechnol. 2024, 15, 965–976, doi:10.3762/bjnano.15.79

• the cap structure [28]. The choice of material depends on the application requirements; silicone rubber may be preferable for applications needing high directionality and easy activation/deactivation, while materials like polyurethane or thermoplastic elastomers are better suited for tolerating slight

• silicone rubber (C, D). Isotropic designs were initially produced with polyurethane, and then structural materials were swapped to thermoplastic elastomers, with directional adhesion created by deliberate defects in the caps (D). Electrically conductive composite versions and geckofluidics were created in

Ultrasensitive and ultrastretchable metal crack strain sensor based on helical polydimethylsiloxane

• Shangbi Chen,
• Dewen Liu,
• Weiwei Chen,
• Huajiang Chen,
• Jiawei Li and
• Jinfang Wang

Beilstein J. Nanotechnol. 2024, 15, 270–278, doi:10.3762/bjnano.15.25

• structure consisting of a sensing layer composed of CNTs and MXene on a flexible thermoplastic polyurethane substrate [34]. The strain sensor exhibits exceptional sensing range (390%) and sensitivity (GF = 2159.5). These findings highlight the importance of rational design of geometric structures and

Hierarchically patterned polyurethane microgrooves featuring nanopillars or nanoholes for neurite elongation and alignment

• Lester Uy Vinzons,
• Guo-Chung Dong and
• Shu-Ping Lin

Beilstein J. Nanotechnol. 2023, 14, 1157–1168, doi:10.3762/bjnano.14.96

• approaches are quite limited. In this work, we show that nanopillars and nanoholes, and their combination with microgrooves, can be patterned on polyurethane (PU) films using a low-cost, reusable photoresist master mold prepared via nanosphere lens lithography and UV-LED photolithography, with specific

• -cost SU-8 substrates can be used as a reusable master mold to create nano-/micropatterns on polyurethane (PU), a soft, versatile material that has been used for nerve conduits [17]; and finally, by showing, for the first time, significant enhancement of both PC12 neurite elongation and alignment on the

Polymer nanoparticles from low-energy nanoemulsions for biomedical applications

• Santiago Grijalvo and
• Carlos Rodriguez-Abreu

Beilstein J. Nanotechnol. 2023, 14, 339–350, doi:10.3762/bjnano.14.29

• properties, drug loading, and drug release are discussed. We highlight the utilization of ethyl cellulose, poly(lactic-co-glycolic acid), and polyurethane/polyurea in the field of nanomedicine as potential drug delivery systems. Advances are still needed to achieve better control over size distribution

• , nanoparticle concentration, surface functionalization, and the type of polymers that can be processed. Keywords: ethyl cellulose; nanoemulsions; nanomedicine; phase inversion composition (PIC) method; PLGA; polymer nanoparticles; polyuria; polyurethane; surfactants; Review 1 Introduction The field of

• nanoemulsions and derived PLGA nanoparticles discussed above are summarized in Table 2. 3.3 Polyurethane and polyurea nanoparticles Polyurethane and polyurea are polymers that can be made biocompatible and display superior physicochemical properties. Therefore, they are attractive for biomedical applications

Structural, optical, and bioimaging characterization of carbon quantum dots solvothermally synthesized from o-phenylenediamine

• Zoran M. Marković,
• Milica D. Budimir,
• Martin Danko,
• Dušan D. Milivojević,
• Pavel Kubat,
• Danica Z. Zmejkoski,
• Vladimir B. Pavlović,
• Marija M. Mojsin,
• Milena J. Stevanović and
• Biljana M. Todorović Marković

Beilstein J. Nanotechnol. 2023, 14, 165–174, doi:10.3762/bjnano.14.17

• time, carbon quantum dots were prepared from o-phenylenediamine dissolved in toluene by a solvothermal route. Subsequently, the prepared carbon quantum dots were encapsulated into polyurethane films by a swelling–encapsulation–shrink method. Analyses of the results obtained by different

• synthesis by a solvothermal method. The prepared CQDs were encapsulated into medical grade polyurethane (PU) films by a swelling–encapsulation–shrink method. It was investigated how the precursor influenced the structure (morphology and chemical composition) and further prooxidative, antibacterial, and

• cytotoxic properties of CQDs and CQD/polyurethane composites. Results and Discussion Surface morphology Figure S1 (Supporting Information File 1) presents the surface morphology of the CQD samples. Figure S1a shows a TEM micrograph of CQDs. The average diameter of these dots is 4 ± 1 nm. A top-view AFM

Utilizing the surface potential of a solid electrolyte region as the potential reference in Kelvin probe force microscopy

• Nobuyuki Ishida

Beilstein J. Nanotechnol. 2022, 13, 1558–1563, doi:10.3762/bjnano.13.129

• approximately 10 mm × 20 mm, and ultrasonically cleaned in ethanol. Subsequently, a 30 nm thick Au electrode was deposited by resistance-heating evaporation using a crucible in a vacuum chamber. A polyurethane-coated Cu wire (25 μm diameter) was used as a mask to pattern the electrode shapes, as shown in Figure

Biomimetic chitosan with biocomposite nanomaterials for bone tissue repair and regeneration

• Se-Kwon Kim,
• Sesha Subramanian Murugan,
• Pandurang Appana Dalavi,
• Sebanti Gupta,
• Sukumaran Anil,
• Gi Hun Seong and
• Jayachandran Venkatesan

Beilstein J. Nanotechnol. 2022, 13, 1051–1067, doi:10.3762/bjnano.13.92

• , polyhydroxyethylmethacrylate, and polyethylene glycol were used in composite preparation for bone tissue engineering applications [10]. To create a fibrous scaffold for bone tissue regeneration, zein and chitosan were combined with polyurethane and functionalized multiwalled carbon nanotubes. The developed scaffolds have

A comprehensive review on electrospun nanohybrid membranes for wastewater treatment

• Senuri Kumarage,
• Imalka Munaweera and
• Nilwala Kottegoda

Beilstein J. Nanotechnol. 2022, 13, 137–159, doi:10.3762/bjnano.13.10

• particulate matter. Ge et al. developed an electrospun nanocomposite with rare earth-fused polyurethane to adsorb volatile organic compounds, which are air pollutants [16]. Al-Attabi et al. fabricated a nanohybrid for the submicrometer aerosol particle size filtration by doping wrinkled silica into PAN via

Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications

• Sepand Tehrani Fateh,
• Lida Moradi,
• Elmira Kohan,
• Michael R. Hamblin and
• Amin Shiralizadeh Dezfuli

Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64

Photothermally active nanoparticles as a promising tool for eliminating bacteria and biofilms

• Mykola Borzenkov,
• Piersandro Pallavicini,
• Angelo Taglietti,
• Laura D’Alfonso,
• Maddalena Collini and
• Giuseppe Chirico

Beilstein J. Nanotechnol. 2020, 11, 1134–1146, doi:10.3762/bjnano.11.98

• in 77% planktonic P. aeruginosa cell death. In addition, polyurethane nanocomposites containing the same hybrid nanomaterials were also able to eliminate all the surface-grafted P. aeruginosa cells under NIR light irradiation. Reduced graphene oxide, which is characterized by a broad absorption

Upcycling of polyurethane waste by mechanochemistry: synthesis of N-doped porous carbon materials for supercapacitor applications

• Christina Schneidermann,
• Pascal Otto,
• Desirée Leistenschneider,
• Sven Grätz,
• Claudia Eßbach and
• Lars Borchardt

Beilstein J. Nanotechnol. 2019, 10, 1618–1627, doi:10.3762/bjnano.10.157

• Innovation Centre for Engineering, 9211 - 116 Street, AB T6G 1H9 Edmonton, Canada Ruhr-Universität Bochum, Department of Inorganic Chemistry, Universitätsstrasse 150, 44801 Bochum, Germany 10.3762/bjnano.10.157 Abstract We developed an upcycling process of polyurethane obtaining porous nitrogen-doped carbon

• materials that were applied in supercapacitor electrodes. In detail, a mechanochemical solvent-free one-pot synthesis is used and combined with a thermal treatment. Polyurethane is an ideal precursor already containing nitrogen in its backbone, yielding nitrogen-doped porous carbon materials with N content

• EMIM-BF4 (70 F·g−1). Keywords: mechanochemistry; polyurethane; porous carbon; supercapacitor; waste; Introduction Currently more than 275 million tons of plastics end up as waste every year, 12.7 million tons of which accumulate in the oceans [1][2]. This waste is mainly packaging materials such as

The effect of flexible joint-like elements on the adhesive performance of nature-inspired bent mushroom-like fibers

• Elliot Geikowsky,
• Serdar Gorumlu and
• Burak Aksak

Beilstein J. Nanotechnol. 2018, 9, 2893–2905, doi:10.3762/bjnano.9.268

• resultant bending moment when compared to a monolithically constructed fiber. Inspired by the construction and the material composition of beetle setal arrays as shown in Figure 1a, bent mushroom-like fiber arrays are fabricated from polyurethane materials using a stiff stalk, a softer tip, and joint-like

• elements with varying elastic modulus as shown in Figure 1b. Using these fibers, the effect of the elastic modulus of the joint between the stalk and the tip on adhesion and friction is investigated. All the fiber array stalks and the tips are made of polyurethane with elastic modulus Es = 126 MPa and Et

• = 8.89 MPa, respectively. The polyurethane used to fabricate the stiff stalks has a considerably higher elastic modulus that what has traditional been utilized for bioinspired microscale fibrillar adhesives to date. The fabrication technique to generate high aspect ratio, tilted fibers enhances

Electrospun one-dimensional nanostructures: a new horizon for gas sensing materials

• Muhammad Imran,
• Nunzio Motta and
• Mahnaz Shafiei

Beilstein J. Nanotechnol. 2018, 9, 2128–2170, doi:10.3762/bjnano.9.202

• polyurethane (PU) nanofibers using electrospinning [64]. These nanoparticles embedded in polymer nanofibers could be promising materials for room temperature gas sensing. Furthermore, graphene oxide (GO) sheets have also been incorporated with electrospun polyacrylonitrile (PAN) fibers [65][66][67]. The fibers

Engineering of oriented carbon nanotubes in composite materials

• Razieh Beigmoradi,
• Abdolreza Samimi and
• Davod Mohebbi-Kalhori

Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41

• application is limited to the laboratory because of the inhomogeneous stretching ratio at the edge of films need manual operation and a skillful operator [17]. Fracture stretching An ultimate case of stretching is known as fracture and occurs when a hard polymer composite comprising CNTs, such as polyurethane

Bi-layer sandwich film for antibacterial catheters

• Gerhard Franz,
• Florian Schamberger,
• Hamideh Heidari Zare,
• Sara Felicitas Bröskamp and
• Dieter Jocham

Beilstein J. Nanotechnol. 2017, 8, 1982–2001, doi:10.3762/bjnano.8.199

• detected a bacterial resistance against silver by molecular genetics [10]. The impact is not predictable, because this was a single result of research. Briefly, plates of organic polymers (polyurethane) were coated with evaporated silver films, hatched into small pieces and added to the highly viscous

• this layer does not consist of a continuous film on top of the substrate (polysilicone or polyurethane), but if small grains or stripes are encased by the organic polymer. This polymer is deposited directly on the substrate, and the adhesion between an organic substrate and the organic polymer is

• expected to be far better than the adhesion of silver atop polysilicone or polyurethane. Also, the thickness of the protecting porous layer determines the maximum of the depot layer. For a long durability, the thickness should be as high as possible. For a stable and reliable sandwich system, the thickness

Preparation of thick silica coatings on carbon fibers with fine-structured silica nanotubes induced by a self-assembly process

• Benjamin Baumgärtner,
• Hendrik Möller,
• Thomas Neumann and
• Dirk Volkmer

Beilstein J. Nanotechnol. 2017, 8, 1145–1155, doi:10.3762/bjnano.8.116

• fibers can enhance adhesion to both polyurethane and epoxy resins matrices [32]. A chemical modification of carbon fibers with tetraethylenepentamine (TEPA) was presented as a possible option. For an effective binding of TEPA via amide functional groups, the number of carboxylic acid groups on the carbon

Intercalation and structural aspects of macroRAFT agents into MgAl layered double hydroxides

• Dessislava Kostadinova,
• Ana Cenacchi Pereira,
• Muriel Lansalot,
• Franck D’Agosto,
• Elodie Bourgeat-Lami,
• Fabrice Leroux,
• Christine Taviot-Guého,
• Sylvian Cadars and
• Vanessa Prevot

Beilstein J. Nanotechnol. 2016, 7, 2000–2012, doi:10.3762/bjnano.7.191

• ], elastomers [27], epoxy polymers [28], poly(ε-caprolactone) [29], polyesters [30], polyurethane [31] and polyimide [21]. Alternatively, Leroux et al. described the preparation of a hybrid LDH phase intercalated by an anionic polymerizable surfactant acting further as an anchor that compatibilizes the

False positives and false negatives measure less than 0.001% in labeling ssDNA with osmium tetroxide 2,2’-bipyridine

• Anastassia Kanavarioti

Beilstein J. Nanotechnol. 2016, 7, 1434–1446, doi:10.3762/bjnano.7.135

• detector (DAD) and Chemstation software, Rev.B.04.02 SP1, for data acquisition and processing. Only glass-type CE vials were used, as OsBp was found to react with polyurethane vials, lowering its effective concentration. Untreated fused silica capillaries (short: 50 μm × 40 cm and long: 50 μm × 72 cm) with

Organic and inorganic–organic thin film structures by molecular layer deposition: A review

• Pia Sundberg and
• Maarit Karppinen

Beilstein J. Nanotechnol. 2014, 5, 1104–1136, doi:10.3762/bjnano.5.123

• corresponding to a vapor pressure of 2 mbar, which is a rather typical pressure used for ALD/MLD depositions. Organic thin films So far MLD has been used to produce polyamide, polyimide, polyimide–amide, polyurea, polyurethane, polythiurea, polyester and polyimine thin films. In Table 2, we list the

• are 13.5, 17.2, 20.9, and 17.2 Å, the growth rates of the polymers were considerably less than a full monolayer per cycle [73]. Polyurethanes As with polyureas, the reaction in which polyurethane formation takes place involves an isocyanate, but instead of an amine, an alcohol is required for the

The optimal shape of elastomer mushroom-like fibers for high and robust adhesion

• Burak Aksak,
• Korhan Sahin and
• Metin Sitti

Beilstein J. Nanotechnol. 2014, 5, 630–638, doi:10.3762/bjnano.5.74

• mushroom-like polyurethane fibers [32][37]. The DB cohesive zone model is implemented and modified slightly to avoid divergence of the numerical solution. Step function from zero stress to σo in the cohesive zone model is replaced with a high stiffness relation between the attractive stress and interfacial

• al. [32]. Both Heepe et al. and Varenberg et al. presented experimental results with mushroom-like fibers by using high speed imaging and showed that the detachment of the fiber was initiated with an internal crack. Similarly, Murphy et al. observed under tensile loading of polyurethane mushroom-like

• polyurethane mushroom-like fibers with 4 µm stalk radius, 8 µm tip radius, and 20 µm height. Two-dimensional axial symmetry model for a mushroom-like fiber. The tip (top surface) is fixed in radial direction to simulate full-friction contact. DB cohesive zone model is implemented at the tip of the fiber in FE

Dynamic nanoindentation by instrumented nanoindentation and force microscopy: a comparative review

• Sidney R. Cohen and
• Estelle Kalfon-Cohen

Beilstein J. Nanotechnol. 2013, 4, 815–833, doi:10.3762/bjnano.4.93

Mapping mechanical properties of organic thin films by force-modulation microscopy in aqueous media

• Jianming Zhang,
• Zehra Parlak,
• Carleen M. Bowers,
• Terrence Oas and
• Stefan Zauscher

Beilstein J. Nanotechnol. 2012, 3, 464–474, doi:10.3762/bjnano.3.53

• binding to the gold surface. Protein patterns were prepared by dry stamping of the tandem B-domains on to the gold substrate surface, by using a polyurethane (pUA) stamp (15 µm hexagon). The pUA stamp was UV cross-linked on a silicon master with hexagonal pattern features and, before each use, cleaned by