Luminescent supramolecular hydrogels from a tripeptide and nitrogen-doped carbon nanodots

• Maria C. Cringoli,
• Slavko Kralj,
• Marina Kurbasic,
• Massimo Urban and
• Silvia Marchesan

Beilstein J. Nanotechnol. 2017, 8, 1553–1562, doi:10.3762/bjnano.8.157

• address demanding therapeutic challenges [18]. In 2015, Steed et al. reported CND–hydrogel hybrids obtained from bis(urea) derivatives used as LMWGs [19] that displayed considerable fluorescence enhancement relative to CNDs alone and showed promising performance in silver ion selective determination [20

• hydrogels following a pH change, while their homochiral stereoisomers did not. In particular, the tripeptide DLeu-Phe-Phe, which was chosen for the present study, immediately formed a self-supporting hydrogel [25]. In a typical protocol, the tripeptide was first dissolved as an anion in an alkaline buffer

• by rheometry, fluorescence, circular dichroism (CD), FTIR spectroscopy, transmission electron microscopy (TEM), and differential scanning calorimetry (DSC). Given that this tripeptide is capable of forming a hydrogel with mild antimicrobial activity and a lack of cytotoxicity in vitro [26], this new

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

• room temperature resulted in a hydrogel or polymer particles, respectively, which were added to 1 mL of a mixture of tetramethyl orthosilicate (Aldrich) and ethanol (1:1 by volume) after a period of 12 h. The mineralization time was 40 min. The precipitated silica particles were separated via

Synthesis of coaxial nanotubes of polyaniline and poly(hydroxyethyl methacrylate) by oxidative/initiated chemical vapor deposition

• Alper Balkan,
• Efe Armagan and
• Gozde Ozaydin Ince

Beilstein J. Nanotechnol. 2017, 8, 872–882, doi:10.3762/bjnano.8.89

• . The fabrication process involves the deposition of an outer layer of the conductive polyaniline (PANI) by oxidative chemical vapor deposition, followed by the deposition of the inner layer of poly(2-hydroxyethyl methacrylate) (pHEMA) hydrogel by initiated chemical vapor deposition. The vapor-phase

• PANI nanotubes, the resistance changed parabolically with relative humidity because of competing effects of doping and swelling of the PANI polymer under humid conditions. Introducing a hydrogel inner layer increased the overall resistance, and enhanced swelling, which caused the resistance to

• oxide (AAO) track-etch membranes. The ability to control the thickness with high sensitivity using these vapor phase techniques allowed to produce coaxial nanotubes. The response of these nanotubes to the changes in humidity could be tuned by introducing the hydrogel inner layer. Results and Discussion

Recombinant DNA technology and click chemistry: a powerful combination for generating a hybrid elastin-like-statherin hydrogel to control calcium phosphate mineralization

• Mohamed Hamed Misbah,
• Mercedes Santos,
• Luis Quintanilla,
• Christina Günter,
• Matilde Alonso,
• Andreas Taubert and
• José Carlos Rodríguez-Cabello

Beilstein J. Nanotechnol. 2017, 8, 772–783, doi:10.3762/bjnano.8.80

• , different in morphology and composition, into the hydrogel matrices [21]. In order to obtain a hydrogel system that can control the formation of CP, it is important to combine different approaches with each other to overcome the challenges inherent to generating materials with the desired properties

• combined with SNA15 in soluble state has been investigated so far [13][31], to our best knowledge, there is only one study about the mineralization of ELRs in a hydrogel state [21]. In this study, Li et al. developed mineralized ELR-hydrogels using a polymer induce liquid precursor (PILP) mineralization

• process where the poly aspartic acids (poly Asp) mimic the role of non-collagenous proteins (NCPs) in biominerals. Although, poly Asp may facilitate the infiltration of ACP into the ELR hydrogel, the interaction of poly Asp with the ELR was not stated. However, to the best our knowledge, the foundations

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

• nanocomposite hydrogel (TGH) was prepared by Zhang et al. by a facile one-pot hydrothermal approach where the spherical nanostructured TiO2 NPs were densely decorated onto the GS [89]. A 2D graphene–TiO2 sandwich structure was prepared by using ethylenediamine/H2O solvent in a reduction–hydrolysis technique

• (Figure 5). Chen et al. have prepared graphene/γ-Fe2O3 hybrid aerogels for the first time which are used for biocatalytic transformation [148]. Fe2O3 supported on a N-graphene hydrogel was prepared by a facial one-pot hydrothermal method by Ma et al. and is used as an advanced supercapacitor electrode

Streptavidin-coated gold nanoparticles: critical role of oligonucleotides on stability and fractal aggregation

• Roberta D'Agata,
• Pasquale Palladino and
• Giuseppe Spoto

Beilstein J. Nanotechnol. 2017, 8, 1–11, doi:10.3762/bjnano.8.1

• by using a SensiQ Pioneer equipment from SensiQ Technologies, Inc. (Oklahoma City, USA). Chips for SPR were purchased from ICx Nomadics (Oklahoma City, USA). SA was immobilized at 25 °C on the carboxylated hydrogel matrix of COOH5 sensor chips through the standard amine-coupling method. For this

Nano- and microstructured materials for in vitro studies of the physiology of vascular cells

• Alexandra M. Greiner,
• Adria Sales,
• Hao Chen,
• Sarah A. Biela,
• Dieter Kaufmann and
• Ralf Kemkemer

Beilstein J. Nanotechnol. 2016, 7, 1620–1641, doi:10.3762/bjnano.7.155

• hydrogel and thus its stiffness can be varied. Their elasticity can be tuned over a wide range from below 1 kPa to above 100 MPa [79]. An additional feature of PEG hydrogels is their low protein absorption. This characteristic makes them often to the coating material of choice when surfaces need to have

• , crosslinker and photoinitiator, as well as the intensity of UV light and the exposure time, the pore size of the hydrogel and consequently the elasticity can be tuned. Stiffness from PAA hydrogels can be tuned from ca. 50 Pa to more than 700 kPa [50][114][115][116]. Due to their easy availability and handling

• , PAA gels have found frequent application in cell mechanics studies [50][114][115][116][164][165]. PDMS is an elastomeric material [6][61][103][104][105][106]. Unlike PEG and PAA, PDMS is not a hydrogel but a hydrophobic polymer. Variation in hydrogel stiffness changes usually the meshwork properties

Synthesis and applications of carbon nanomaterials for energy generation and storage

• Marco Notarianni,
• Jinzhang Liu,
• Kristy Vernon and
• Nunzio Motta

Beilstein J. Nanotechnol. 2016, 7, 149–196, doi:10.3762/bjnano.7.17

Fabrication of hybrid nanocomposite scaffolds by incorporating ligand-free hydroxyapatite nanoparticles into biodegradable polymer scaffolds and release studies

• Balazs Farkas,
• Marina Rodio,
• Ilaria Romano,
• Alberto Diaspro,
• Romuald Intartaglia and
• Szabolcs Beke

Beilstein J. Nanotechnol. 2015, 6, 2217–2223, doi:10.3762/bjnano.6.227

• % released HA NPs. This release mechanism fits well to our empirical observations concerning the degradation of high stiffness PPF scaffolds in DMEM: the material becomes a hydrogel during the first two weeks, then disperses into the medium in the next 4–6 weeks. Such degradation obviously leads to a ramp up

• in the release mechanism due to the hydrogel transition phase. Of note, the experiment had to be cancelled after 2 weeks due to contamination: the vials became infected by fungi, gradually digesting the nanoparticles (data not shown). Conclusion We presented the combination of two laser processing

• and degradation of HA NP-incorporated polymer scaffolds are presented during its degradation in DMEM. The scaffold becomes hydrogel, swells and releases the HA NPs. The plot shows the released fraction in percent as a function of the time, estimated by inductively coupled spectrometry (ICP-EOS). a

Self-assembled anchor layers/polysaccharide coatings on titanium surfaces: a study of functionalization and stability

• Ognen Pop-Georgievski,
• Dana Kubies,
• Josef Zemek,
• Neda Neykova,
• Roman Demianchuk,
• Eliška Mázl Chánová,
• Miroslav Šlouf,
• Milan Houska and
• František Rypáček

Beilstein J. Nanotechnol. 2015, 6, 617–631, doi:10.3762/bjnano.6.63

• and a thin, alginate hydrogel could be used in bone tissue engineering as a scaffold material that provides biologically active molecules. The main objective of this contribution is to characterize the activation and the functionalization of titanium surfaces by the covalent immobilization of

• a long-term immersion. Based on the stability observations, the alginate monolayers bound to the neridronate or PDA anchor layers can be potentially used for the immobilization of a thin alginate hydrogel carrier of bioactive compounds (such as calcium phosphates or other biologically active

• siloxane network led to a higher deterioration tendency of the ALG/APTES double layer. The presented surface modification strategy of titanium can be an effective path for the formation of ALG-based hydrogel coatings enriched with bioactive compounds for bone tissue engineering applications. Experimental

Multifunctional layered magnetic composites

• Maria Siglreitmeier,
• Baohu Wu,
• Tina Kollmann,
• Martin Neubauer,
• Gergely Nagy,
• Dietmar Schwahn,
• Vitaliy Pipich,
• Damien Faivre,
• Dirk Zahn,
• Andreas Fery and
• Helmut Cölfen

Beilstein J. Nanotechnol. 2015, 6, 134–148, doi:10.3762/bjnano.6.13

• material is based on an already established three step protocol [34]. In the first step, the gelatin hydrogel is infiltrated into the demineralized nacre matrix through a vacuum infiltration process [35], in the second step this chitin–gelatin composite is introduced into a solution of ferrous (FeCl2 0.1 M

• ) and ferric ions (FeCl3 0.2 M) in a molar ratio of 1:2. After complete diffusion of the ions inside the hydrogel template magnetite is precipitated in the third step by introducing the template in a base (NaOH 0.1 M). The magnetite nanoparticles are synthesized through a so-called co-precipitation

• magnetite nanoparticles, which act as additional crosslinkers in the gelatin hydrogel. This effect was discovered before for the studies of magnetic hydrogels [34] and shows similar values for the swelling degree. We can conclude that the gelatin hydrogel as well as the magnetic hydrogel do not change their

Biopolymer colloids for controlling and templating inorganic synthesis

• Laura C. Preiss,
• Katharina Landfester and
• Rafael Muñoz-Espí

Beilstein J. Nanotechnol. 2014, 5, 2129–2138, doi:10.3762/bjnano.5.222

• supports (e.g., metallization or mineralization of DNA) or by using particle systems. Hydrogel approaches can also be confined to the spaces of particles. Clearly, synthetic polymers are often a more economic and versatile alternative, but biopolymers can be especially interesting in those applications in

Effect of silver nanoparticles on human mesenchymal stem cell differentiation

• Christina Sengstock,
• Jörg Diendorf,
• Matthias Epple,
• Thomas A. Schildhauer and
• Manfred Köller

Beilstein J. Nanotechnol. 2014, 5, 2058–2069, doi:10.3762/bjnano.5.214

• nanomaterials have been used in numerous devices and products, such as silver sulfadiazine in the treatment of burns to reduce skin infections. Furthermore, silver has been used to coat a variety of different surfaces, such as catheters [4][5][6][7], or it has been incorporated into a hydrogel network for wound

Influence of the PDMS substrate stiffness on the adhesion of Acanthamoeba castellanii

• Sören B. Gutekunst,
• Carsten Grabosch,
• Alexander Kovalev,
• Stanislav N. Gorb and
• Christine Selhuber-Unkel

Beilstein J. Nanotechnol. 2014, 5, 1393–1398, doi:10.3762/bjnano.5.152

• the adhesion of A. castellanii to hydrogel materials used in contact lenses [39]. We determined a very strong dependence of A. castellanii adhesion on the water content of contact lens materials, i.e., a strong increase in adhesion with increasing water content. In the study presented here, the PDMS

Controlling mechanical properties of bio-inspired hydrogels by modulating nano-scale, inter-polymeric junctions

• Seonki Hong,
• Hyukjin Lee and
• Haeshin Lee

Beilstein J. Nanotechnol. 2014, 5, 887–894, doi:10.3762/bjnano.5.101

• quinone tanning. The hydrogels produced by catecholamine crosslinking using 6Arm-PEG-NH-catechol exhibited enhanced mechanical properties and rapid gelation compared to the hydrogel prepared by PEGs that can only use catechol-catechol crosslinking. This study demonstrates that the chemical configuration

• the effect of the amine group in PEG gelation, we prepared 6Arm-PEG-NH-catechol and 6Arm-PEG-catechol (control). Both were dissolved in PBS pH 8.0 with a final concentration of 3% (w/v). It is expected that the hydrogel formed by amine-catechol involved tanning (6Arm-PEG-NH-catechol) may exhibit

• completed within 10 min. The elastic modulus of the hydrogel made of 6Arm-PEG-NH-catechol was about 1,000 Pa, but the G’ of the hydrogel prepared by 6Arm-PEG-catechol was low, as expected (about 500 Pa). The two-times increase in the elastic modulus indicates that amine-catechol quinone tanning is more

Biocalcite, a multifunctional inorganic polymer: Building block for calcareous sponge spicules and bioseed for the synthesis of calcium phosphate-based bone

• Xiaohong Wang,
• Heinz C. Schröder and
• Werner E. G. Müller

Beilstein J. Nanotechnol. 2014, 5, 610–621, doi:10.3762/bjnano.5.72

• cells retain their capacity to synthesize HA crystallites. Furthermore, the mechanical properties, including surface roughness and hardness, of the hydrogel were determined. If silica is included in the hydrogel matrix, the encapsulated SaOS-2 cells were found to increasingly express the gene encoding

• liberation of both orthophosphate (pink filled triangles) and Ca2+, both components are required for the synthesis of HA [(Ca5(PO4)3(OH)]. Partially taken from [58] with permission. Computer-aided rapid prototyping bioprinting. (A-a) A sketch outlining the computer-guided extrusion of Na alginate hydrogel

Growth behaviour and mechanical properties of PLL/HA multilayer films studied by AFM

• Cagri Üzüm,
• Johannes Hellwig,
• Narayanan Madaboosi,
• Dmitry Volodkin and
• Regine von Klitzing

Beilstein J. Nanotechnol. 2012, 3, 778–788, doi:10.3762/bjnano.3.87

• , back in 1993 [9]. Further measurements include different strains of E. coli with a colloidal probe [10], elastic modulus of human platelet cells [11], human bone cell or skeletal muscle cells [12], breast cancer cells [13][14], hydrogel films [15][16][17], or nanoribbons [18], as well as single

• hydrogel particles [19][20][21][22]. Recent advances in the area have been summarized by Picart and co-workers [23][24]. Several studies on the bio-applicability of polymer-based films showed that if cells are deposited on a surface with an elasticity gradient, they move from the softer region to a

Determination of object position, vortex shedding frequency and flow velocity using artificial lateral line canals

• Adrian Klein and
• Horst Bleckmann

Beilstein J. Nanotechnol. 2011, 2, 276–283, doi:10.3762/bjnano.2.32

• (cf. Equation 2). According to a recent study an artificial cupula made out of hydrogel can improve the performance of artificial sensory hairs (ANs) by about two orders of magnitude. Minimal thresholds were as low as 2.5 μm/s [33]. Thus, one should be able to increase further the sensitivity of ALLCs