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Search for "polymers" in Full Text gives 533 result(s) in Beilstein Journal of Nanotechnology. Showing first 200.
Recent advances in green carbon dots (2015–2022): synthesis, metal ion sensing, and biological applications
Beilstein J. Nanotechnol. 2022, 13, 1068–1107, doi:10.3762/bjnano.13.93
- synthesis of carbon dots Green synthesis of CDs mainly utilizes biomass. Biomass synthesis makes use of natural raw materials (organisms, waste material, protein products, or natural polymers), instead of reaction precursors usually used in the traditional methods, and also requires external energy supply
- materials, are summarized in Table 4. Natural polymer-based CDs Numerous natural polymers, including proteins and polysaccharides, have been used to obtain CDs (Table 5). Chen and co-workers used starch as a source to synthesize graphene quantum dots (CDs) via a one-pot hydrothermal method. They also
- for the bright blue fluorescence of CDs synthesized using citric acid and EDA. It has been established that the CDs are a mixture of IPCA, polymers, and carbon cores [132]. Essner and co-workers carried out the synthesis of CDs using citric acid (paired with urea or ethylenediamine as a nitrogen
Biomimetic chitosan with biocomposite nanomaterials for bone tissue repair and regeneration
Beilstein J. Nanotechnol. 2022, 13, 1051–1067, doi:10.3762/bjnano.13.92
- materials should be in the form of inorganic and organic composites. To mimic the inorganic portion, researchers have tried to utilize calcium phosphate materials due to their similarity to the native tissue. To mimic the organic portion of the bone, several materials including polymers, proteins, and
- and physically comparable microenvironment to that of the natural extracellular matrix, containing healing and stimulating components necessary for bone repair, making them a potential option for bone tissue regeneration. As carbon nanotubes are combined with natural polymers, such as chitosan and
- collagen, they develop an interlinked molecular framework with load-bearing applications and have superior mechanical qualities and biological advantages [57]. A further study reported that carbon nanotubes combined with synthetic polymers of poly-ʟ-lactide acid, polylactic acid
Analytical and numerical design of a hybrid Fabry–Perot plano-concave microcavity for hexagonal boron nitride
Beilstein J. Nanotechnol. 2022, 13, 1030–1037, doi:10.3762/bjnano.13.90
- a SPE (i.e., in-plane dipole) hosted by a 2D hBN layer inside the hybrid plano-concave microcavity. Keywords: Fabry–Perot; hBN; microcavities; plano-concave; polymers; Introduction Pure and indistinguishable SPEs are key components needed for their application in upcoming quantum technologies [1
- microcavities [8], microdisk resonators [9], and photonic crystals [10][11] have been designed and built around color centers in hBN to increase its spontaneous emission by means of Purcell effect. An alternative and low-cost approach to build photonic structures uses polymers to embed different types of SPEs
Bioselectivity of silk protein-based materials and their bio-inspired applications
Beilstein J. Nanotechnol. 2022, 13, 902–921, doi:10.3762/bjnano.13.81
- [97], and peptide isomers known as peptoids, (oligo N-substituted glycines) [98]. In addition, the transfer of the general molecular structure of AMPs/HDPs has led to peptide-mimicking polymers and surface-engineered polymeric-brush-tethered AMPs. These approaches are promising for establishing
Optimizing PMMA solutions to suppress contamination in the transfer of CVD graphene for batch production
Beilstein J. Nanotechnol. 2022, 13, 796–806, doi:10.3762/bjnano.13.70
- ., Cu or Ni) to the desired target substrate (e.g., SiO2/Si, glass, or flexible polymers) often introduces inconsistencies among devices [10]. Various approaches have been developed to address this issue and establish a reproducible transfer process [11][12][13][14][15][16][17]. Among the many, the poly
Recent advances in nanoarchitectures of monocrystalline coordination polymers through confined assembly
Beilstein J. Nanotechnol. 2022, 13, 763–777, doi:10.3762/bjnano.13.67
- Lingling Xia Qinyue Wang Ming Hu Engineering Research Center for Nanophotonics and Advanced Instrument (MOE), School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China 10.3762/bjnano.13.67 Abstract Various kinds of monocrystalline coordination polymers are
- available thanks to the rapid development of related synthetic strategies. The intrinsic properties of coordination polymers have been carefully investigated on the basis of the available monocrystalline samples. Regarding the great potential of coordination polymers in various fields, it becomes important
- to tailor the properties of coordination polymers to meet practical requirements, which sometimes cannot be achieved through molecular/crystal engineering. Nanoarchitectonics offer unique opportunities to manipulate the properties of materials through integration of the monocrystalline building
Fabrication and testing of polymer microneedles for transdermal drug delivery
Beilstein J. Nanotechnol. 2022, 13, 629–640, doi:10.3762/bjnano.13.55
- manufacturing processes for MNs is of considerable interest. This study reports a simple fabrication process for thermoplastic MNs from cycloolefin polymers (COP) using hot embossing on polydimethylsiloxane (PDMS) soft molds. COP has gained interest due to its high molding performance and low cost. The resin
- setting. Keywords: hot embossing; microneedles; penetration efficiency; thermoplastic polymers; two-photon polymerization; Introduction During the past two decades, MN devices have become a promising tool for transdermal drug delivery, vaccination, and point-of-care diagnostics [1][2]. MNs are a
- classified into solid, hollow, coated, hydrogel-forming, and dissolvable types, which depending on the specific medical applications [12][13], are fabricated using silicon, metal, ceramic, silica glass, carbohydrate, and polymers [7][14]. In recent years, polymeric MNs have gained a lot of interest due to
Influence of thickness and morphology of MoS2 on the performance of counter electrodes in dye-sensitized solar cells
Beilstein J. Nanotechnol. 2022, 13, 528–537, doi:10.3762/bjnano.13.44
- DSSCs, which has led researchers to explore efficient cathode materials for DSSCs beyond platinum. To date, Pt replacement materials are divided into three categories, namely carbonaceous materials [2][3][4][5], conductive polymers [5], and transition metal compounds [6][7][8]. Transition metal
Ciprofloxacin-loaded dissolving polymeric microneedles as a potential therapeutic for the treatment of S. aureus skin infections
Beilstein J. Nanotechnol. 2022, 13, 517–527, doi:10.3762/bjnano.13.43
- dissolving polymeric microneedles prepared by a two-layer centrifugation method as a potential treatment of skin infections such as cellulitis. The polymers used were polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP). Two formulations were investigated, namely CIP_MN1, composed of 10 mg ciprofloxacin
- techniques. These microneedles are manufactured of polymers incorporated with medicaments and are intended to dissolve completely in the skin, permitting the medicament to be distributed in deeper skin layers to treat local and systemic infections [5]. Previous studies have shown the advantages of dissolving
- microneedles are based on polymers such as PVA, PVP, chitosan, and poly(lactide-co-glycolide) [19]. In our study, polymer-based microneedles were optimized to achieve a formulation that can efficiently penetrate the skin. In this context, microneedles were studied regarding drug content and penetration of
Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy
Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39
- density of the dark spots is estimated to be (2.0 ± 1.0) × 1012 cm−2 and the corresponding area fraction is approximately 3.2%. Analogous to the formation of 2D polymers on a surface or interface [6], the cross-linking could proceed either by step-growth or chain-growth kinetics. In the step-growth
- . Brighter islands of 5–10 nm in size were still visible, separated by darker structures with a branched form, which can be considered remainders of the ordered layer. Many voids can be observed here. Unlike the dynamic free volume pores of polymers, these voids remain stable after multiple STM scans. By
Tubular glassy carbon microneedles with fullerene-like tips for biomedical applications
Beilstein J. Nanotechnol. 2022, 13, 455–461, doi:10.3762/bjnano.13.38
- most important role in determining the nature of the resulting glassy carbon” [9]. Sharma has also coined the term “polymer-derived carbons” for glassy carbon made by the thermal decomposition of polymers, which accounts for virtually all the glassy carbons found in the literature to date. In this
- article, we have followed the nanoarchitectonics [10] concept to fabricate our glassy carbon material by using methane as building unit and carbon source rather than polymers. There are earlier works on methane pyrolysis in a flow reactor by F. G. Billaud et al. [11] and Z. Bai and co-workers [12]. Bai et
- procedure utilising catalytic methane pyrolysis to fabricate glassy carbon microneedle electrodes for biomedical applications. Results and Discussion Growth of glassy carbon microneedles Previously, glassy carbon microneedles have been made by the pyrolysis of commercially available polymers. The polymer
The role of sulfonate groups and hydrogen bonding in the proton conductivity of two coordination networks
Beilstein J. Nanotechnol. 2022, 13, 437–443, doi:10.3762/bjnano.13.36
- materials are currently being discussed as potential alternatives. These include coordination polymers (CPs), covalent organic frameworks (COFs), polyoxometalates (POMs), hydrogen-bonded organic frameworks (HOFs), and mesoporous organosilica materials (MPOs) [3][9][10][11]. In particular, proton-conducting
- coordination polymers (CPs), such as (porous) metal-organic frameworks (MOFs) and (non-porous, yet cross-linked) coordination networks [12], may offer alternatives to Nafion because of their structural controllability and high crystallinity [13]. The quest to develop new proton-conducting network materials is
A non-enzymatic electrochemical hydrogen peroxide sensor based on copper oxide nanostructures
Beilstein J. Nanotechnol. 2022, 13, 424–436, doi:10.3762/bjnano.13.35
- electrodes by dip- or drop-coating techniques, using a porous substrate or binder polymers [69][76][77]. However, despite the widespread use and simplicity of this method of electrode preparation, it has a number of significant disadvantages. First, there is the problem of homogenization of the
A chemiresistive sensor array based on polyaniline nanocomposites and machine learning classification
Beilstein J. Nanotechnol. 2022, 13, 411–423, doi:10.3762/bjnano.13.34
- sensing mechanism of nanocomposite layers based on PANI was discussed in [10]. Polyaniline is known as one of the most famous p-type conductive polymers. During the exposure to a reducing gas (NH3), the emeraldine salt form of polyaniline is converted to the emeraldine base form leading to an increase in
Micro- and nanotechnology in biomedical engineering for cartilage tissue regeneration in osteoarthritis
Beilstein J. Nanotechnol. 2022, 13, 363–389, doi:10.3762/bjnano.13.31
- osteochondral defects can be overcome by the versatile and efficient methods developed by TE technologies and will be discussed in detail. 3.1 Development of biomaterials using micro and nanostructures for cartilage TE Since Vacanti et al. reported the application of bioabsorbable artificial polymers as
- purposes is the subject of many studies [19] in which natural polymers, synthetic polymers, or their combination were used to provide a biomimetic microenvironment, which not only includes biological cues, but also provides the desired mechanical properties. The progress in materials science has revealed
- . Nanomaterials are defined by the National Nanotechnology Initiative as manufactured or natural materials that have at least one dimension between 1 and 100 nm [33][34][35][36][37][38][39][40][41][42][43][44][45][46]. Nanomaterials are classified as metals, polymers, or ceramics according to their structure and
Alcohol-perturbed self-assembly of the tobacco mosaic virus coat protein
Beilstein J. Nanotechnol. 2022, 13, 355–362, doi:10.3762/bjnano.13.30
- assembly of macromolecular components is well-established with many other systems, including lipids, synthetic polymers, and peptides, but has been the subject of few studies with virus-like particles [28][29][30][31]. Lauffer and Shalaby reported that glycine-based molecules promoted the polymerization of
The effect of metal surface nanomorphology on the output performance of a TENG
Beilstein J. Nanotechnol. 2022, 13, 298–312, doi:10.3762/bjnano.13.25
- improve the surface charge density in the contact electrification process, it is necessary to expand the effective contact surface area by surface engineering of micro-/nanoscale structures [44][45][46]. There are various processes for the surface engineering of polymers with micro-/nanoscale structures
Coordination-assembled myricetin nanoarchitectonics for sustainably scavenging free radicals
Beilstein J. Nanotechnol. 2022, 13, 284–291, doi:10.3762/bjnano.13.23
- antioxidant peptides by proteases. The combination of liposomes or polymers with different payload materials has been reported, for example, PEG-modified liposomes loaded with resveratrol, layer-by-layer-coated gelatin nanoparticles, or Gelucire-based solid lipid and polymeric micelles [14][15][16][17][18][19
Effects of drug concentration and PLGA addition on the properties of electrospun ampicillin trihydrate-loaded PLA nanofibers
Beilstein J. Nanotechnol. 2022, 13, 245–254, doi:10.3762/bjnano.13.19
- different properties with many polymers and solvents [1][2][3][4]. Drug-loaded electrospun polymeric nanofibers have many unique properties, such as accelerating healing, controlled drug release, stimulation of cell growth and proliferation due to their similarity to the extracellular matrix, large surface
- area, high encapsulation efficiency, high porosity, and superior mechanical properties [5][6][7]. In our study, FDA-approved polylactic acid (PLA) and poly(lactic-co-glycolic acid) (PLGA), which are frequently preferred polymers in the production of polymeric nanofibers, were used because they are
- focused on drug-free or hydrophilic drug-loaded PLA/PLGA nanofibers produced with different polymers and solvent systems than those in the current study [8][11]. The current study is important since the effects of PLA/PLGA ratios on nanofiber morphology, nanofiber diameter, in vitro drug release, and
Piezoelectric nanogenerator for bio-mechanical strain measurement
Beilstein J. Nanotechnol. 2022, 13, 192–200, doi:10.3762/bjnano.13.14
- fluoride (PVDF) and other piezoelectric polymers are used in the form of fibers, filaments, and composites. In this research, PVDF nanofibers were developed and integrated onto a knitted fabric to fabricate a piezoelectric device for human body angle monitoring. Scanning electron microscopy and X-ray
- last couple of years. Textile-based sensors, being flexible, are easy to fit in a garment and create no barrier to the wearer. Nowadays, wearable sensors based on conductive threads and conductive polymers are capable of measuring vital signs of the human body [4][5]. Tognetti et al. [6] designed and
A comprehensive review on electrospun nanohybrid membranes for wastewater treatment
Beilstein J. Nanotechnol. 2022, 13, 137–159, doi:10.3762/bjnano.13.10
- provides the manufacturers with membranes of nanometer-scale fibers with high surface area to volume ratio. Also, the low start-up cost, the applicability to a wide range of polymers, the ability to deposit fibers on desired substrates such as metal, glass, microfibrous mats and membranes, and the simple
- polymers have shown a considerable enhancement of their properties and performances when compared to the as-spun fiber membranes [3][4]. The versatility of electrospinning has allowed for the fabrication of many synthetic and natural polymer membranes [5], and ceramic nanofibers as well [6]. The most
- common synthetic polymer membranes such as polycaprolactone (PCL), polyacrylonitrile (PAN), polyacrylic acid (PAA), polysulfones (PSF), polyimides (PI), polyvinyl alcohol (PVA), polystyrene (PS), polyethylene oxide (PEO), poly(vinylidene fluoride) (PVDF) and natural polymers such as gelatin, keratin
A photonic crystal material for the online detection of nonpolar hydrocarbon vapors
Beilstein J. Nanotechnol. 2022, 13, 127–136, doi:10.3762/bjnano.13.9
- ) formation of a sensitive polymer matrix, (b) impregnation of the reagent, (c) immobilization of the reagent and (d) preparation of the sensor elements from molecularly imprinted polymers. Organic solvents are usually detected by using polymer matrix sensors (Table 1) through matrix interaction [7][8][9][15
- ) [5][6][20][21][22][23][24][25][26][27]. The development of a sensor device with molecularly imprinted polymers allows for the determination of organic compounds (nicotinamide, sulfonamides, bisphenol A and diethylstilbestrol) with a more complex structure [12][13][28][29]. The color shift (blueshift
- filling of the structure, the structural heterogeneity within a volume, the presence of foreign chemical substances and the size variation of the matrix and particles during the chemical analysis process. However, one cannot ignore sensors based on molecularly imprinted polymers for the selective
Tin dioxide nanomaterial-based photocatalysts for nitrogen oxide oxidation: a review
Beilstein J. Nanotechnol. 2022, 13, 96–113, doi:10.3762/bjnano.13.7
- TiO2 and BiOBr, recent works reported the successful combination of SnO2 nanomaterials with conjugated polymers such as graphitic carbon nitride (g-C3N4) and polyaniline (PANI), yielding metal-free visible-light-driven photocatalysts for addressing NO gas pollution. Such combinations hold great
Theranostic potential of self-luminescent branched polyethyleneimine-coated superparamagnetic iron oxide nanoparticles
Beilstein J. Nanotechnol. 2022, 13, 82–95, doi:10.3762/bjnano.13.6
- sodium; superparamagnetic iron oxide nanoparticles; Introduction Luminescent materials are of great interest in biotechnology and medicine since they can be utilized in sensors, labelling, and imaging [1][2][3][4][5]. Luminescent proteins, luminescent synthetic polymers, and quantum dots are the most
- popular luminescent materials with advantages and disadvantages [6][7][8][9][10]. Luminescent polymers are either π-conjugated systems with delocalized electrons or polymers with conjugated fluorophores as pendant or end groups [11][12][13]. Conjugated polymers usually suffer from insolubility, which
- limits their processability and hence medical use [13][14]. However, in recent years, amine-containing branched polymers such as polyethyleneimine (PEI) [15][16][17][18][19] and dendrimers such as polyamidoamine (PAMAM) [20][21][22][23][24] are reported as weakly blue luminescing organic materials. The
Nanoscale friction and wear of a polymer coated with graphene
Beilstein J. Nanotechnol. 2022, 13, 63–73, doi:10.3762/bjnano.13.4
- Robin Vacher Astrid S. de Wijn Corrosion and tribology, SINTEF, Richard Birkelands vei 2B, 7034 Trondheim, Norway Institutt for maskinteknikk og produksjon, NTNU, Richard Birkelands vei 2B, 7034 Trondheim, Norway 10.3762/bjnano.13.4 Abstract Friction and wear of polymers at the nanoscale is a
- [5][9][10][11][12][13][14][15][16][17][18][19]. The effect of graphene coatings and their ability to protect against wear depend on the substrate underneath. So far, they have been studied almost exclusively on metals [20][21]. The tribological properties of polymers coated with graphene have barely
- layers of graphene oxide and polyethylenimine. The authors showed that a transfer film of graphene on the polymer leads to lower friction. While to our knowledge there have been no numerical studies of friction on graphene-coated polymers, the graphene–polymer interface has been studied. Rissanou et al
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