Design and characterization of polymeric microneedles containing extracts of Brazilian green propolis

• Camila Felix Vecchi,
• Rafaela Said dos Santos,
• Jéssica Bassi da Silva and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2022, 13, 503–516, doi:10.3762/bjnano.13.42

• mechanically characterized. The results of the mechanical analysis showed that formulations containing 3% of P407 presented the highest compression values in a hard surface, which was also confirmed by the height and base values of the morphological analysis and by the microscopy images. It was possible to

• : development; mechanical; microneedles; propolis extract; technology; Introduction In recent decades, microneedle devices have been widely used for non-invasive dermal delivery of various drugs [1][2][3]. Microneedles (MNs) are large enough to penetrate and open small holes only in the stratum corneum and the

• ethanolic or glycolic extracts of Brazilian green PRP. A 32 full-factorial design was utilized to determine the influence of P407 and PRP extract on the morphology and mechanical characteristics of MNs. They were characterized macroscopically, microscopically, and regarding size and texture, yielding an

Ethosomal (−)-epigallocatechin-3-gallate as a novel approach to enhance antioxidant, anti-collagenase and anti-elastase effects

• Çiğdem Yücel,
• Gökçe Şeker Karatoprak,
• Sena Yalçıntaş and
• Tuğba Eren Böncü

Beilstein J. Nanotechnol. 2022, 13, 491–502, doi:10.3762/bjnano.13.41

• ethosomal formulations containing a potent antioxidant, epigallocatechin-3-gallate (EGCG), and to evaluate their potential for use in cosmetics by determining their antioxidant and antiaging effects. Ethosomes (ETHs) were prepared via mechanical dispersion and characterized in vitro in terms of particle

• was prepared using mechanical dispersion [22][24]. The prepared ETHs consisted of 2–4% (w/v) phospholipids, 15–45% (v/v) ethanol and the effects of phospholipid and ethanol concentration on the characterization properties of the formulations were investigated. The SPC was added to the round-bottomed

Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy

• Patrick Stohmann,
• Sascha Koch,
• Yang Yang,
• Christopher David Kaiser,
• Julian Ehrens,
• Jürgen Schnack,
• Niklas Biere,
• Dario Anselmetti,
• Armin Gölzhäuser and
• Xianghui Zhang

Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39

• create ultrathin carbon nanomembranes (CNMs) [25][26]. Depending on the precursor molecules and the exposure conditions, thickness [27], mechanical stiffness [28], and electronic transport characteristics [29][30] of CNMs can be tailored. Carbon nanomembranes have been applied as electron microscopy

• supports [31][32], mechanical resonators [33], and dielectrics in nanocapacitors [34][35]. It has been shown that CNMs possess subnanometer pores, which can block the passage of most molecules and ions, but let water and helium pass through, enabling the use of CNMs in molecular filtration and ion

A non-enzymatic electrochemical hydrogen peroxide sensor based on copper oxide nanostructures

• Irena Mihailova,
• Vjaceslavs Gerbreders,
• Marina Krasovska,
• Eriks Sledevskis,
• Valdis Mizers,
• Andrejs Bulanovs and
• Andrejs Ogurcovs

Beilstein J. Nanotechnol. 2022, 13, 424–436, doi:10.3762/bjnano.13.35

• response and, as a consequence, the selectivity of the sensor. This type of sensor is characterized by good reproducibility of measurement, low production cost, fast response, high sensitivity and selectivity, and chemical and mechanical stability in aggressive environments [40][41][42][43][44][45][46

• mechanical stability, and can, thus, be easily damaged during production, storage, and measurement. These disadvantages can be avoided by using an in situ growth process of CuO nanostructures directly on a copper substrate, in the presence of certain surfactants or additives. This method makes it possible to

• describes the preparation of a nanostructured coating of CuO and its application as a working electrode for the electrochemical determination of H2O2. The resulting coating is distinguished by high homogeneity and adhesion to the copper wire, which ensures high mechanical and chemical resistance of the

Effect of sample treatment on the elastic modulus of locust cuticle obtained by nanoindentation

• Chuchu Li,
• Stanislav N. Gorb and
• Hamed Rajabi

Beilstein J. Nanotechnol. 2022, 13, 404–410, doi:10.3762/bjnano.13.33

• Chuchu Li Stanislav N. Gorb Hamed Rajabi Functional Morphology and Biomechanics, Institute of Zoology, Kiel University, Kiel, Germany Division of Mechanical Engineering and Design, School of Engineering, London South Bank University, London, UK 10.3762/bjnano.13.33 Abstract Cuticle is one of the

• most abundant, but least studied, biological composites. As a result, it has contributed very little to the field of biomimetics. An important step to overcome this problem is to study cuticle biomechanics by means of accurate mechanical measurements. However, due to many reasons, mechanical testing on

• : biomimetics; cuticle; locust; material properties; mechanical testing; nanoindentation; water content; Introduction Cuticle is a lightweight material that forms the whole exoskeleton of insects, from the flexible intersegmental membrane to the stiff jaws and claws. Cuticle of each insect body part has

Electrostatic pull-in application in flexible devices: A review

• Teng Cai,
• Yuming Fang,
• Yingli Fang,
• Ruozhou Li,
• Ying Yu and
• Mingyang Huang

Beilstein J. Nanotechnol. 2022, 13, 390–403, doi:10.3762/bjnano.13.32

• pull-in as the working mechanism have attracted researcher’s attention because of the low cost and the simple structures. Extensive research has shown that modeling the bending of the flexible devices is only limited to the mechanical behavior of the flexible interconnect lines, and hardly involves the

• . The voltage between the plates creates an electrostatic force that causes the upper plate to move down, and the spring provides a restoring force that prevents it from moving. When the applied voltage is lower than the pull-in voltage, the electrostatic force and mechanical recovery force on the upper

• should be considered first. Electrostatic NEM switches The simplest application of the pull-in phenomenon are NEM switches, which are the basis for the other component or system level applications. NEM switches represent a class of nanoscale devices, integrating both electrical and mechanical

Micro- and nanotechnology in biomedical engineering for cartilage tissue regeneration in osteoarthritis

• Zahra Nabizadeh,
• Mahmoud Nasrollahzadeh,
• Hamed Daemi,
• Mohamadreza Baghaban Eslaminejad,
• Ali Akbar Shabani,
• Mehdi Dadashpour,
• Majid Mirmohammadkhani and
• Davood Nasrabadi

Beilstein J. Nanotechnol. 2022, 13, 363–389, doi:10.3762/bjnano.13.31

• the mechanical properties of cartilage [7][9]. Collagen type II is believed to account for 75% of fetal collagen. This amount increases to 90% in mature adults. Collagen type II is found in articular cartilage and the eyes and is considered an indicator of hyaline cartilage [7]. Collagen synthesis is

• slow and plays a critical role in cartilage functionality and homeostasis. Therefore, any degradation would result in the damage and failure of cartilage to withstand mechanical loads. Hyaluronic acid (HA) is an unbranched polysaccharide with a high molecular weight, which plays a major role in

• gathering and aggregating proteoglycans due to the high affinity of aggrecan for it [10] (Figure 2). Hence, articular cartilage is a negatively charged complex of collagen fibers and HA conjugated proteoglycans highly organized into a stratified structure, which can withstand mechanical stresses [6]. The

Selected properties of Al_xZn_yO thin films prepared by reactive pulsed magnetron sputtering using a two-element Zn/Al target

• Witold Posadowski,
• Artur Wiatrowski,
• Jarosław Domaradzki and
• Michał Mazur

Beilstein J. Nanotechnol. 2022, 13, 344–354, doi:10.3762/bjnano.13.29

• manufacturing transparent electrodes, the TCO films should have relatively low resistivity, ρTCO ≤ 10−3 Ω·cm, and optical transmittance, preferably over 80%, for films with thicknesses not exceeding 200 nm. In addition, parameters such as high resistance to mechanical exposure and good adhesion to the substrate

Interfacial nanoarchitectonics for ZIF-8 membranes with enhanced gas separation

• Season S. Chen,
• Zhen-Jie Yang,
• Chia-Hao Chang,
• Hoong-Uei Koh,
• Sameerah I. Al-Saeedi,
• Kuo-Lun Tung and
• Kevin C.-W. Wu

Beilstein J. Nanotechnol. 2022, 13, 313–324, doi:10.3762/bjnano.13.26

• current membrane separation market in chemical engineering is dominated by polymeric membranes because of their low cost, ease of production, and mechanical flexibility [6][7][8][9]. However, applications of polymeric membranes in the separation processes are limited by their short lifetime and inferior

• substrate, the pore size of which is larger than 100 nm (Figure 6a,b) [42]. These embedded ZIF-8 membranes indicated a greater mechanical strength and thermal stability owing to the intrinsic properties of the porous ceramic support [43]. Counter-diffusion synthesis was also adopted in this study to be

The effect of metal surface nanomorphology on the output performance of a TENG

• Yiru Wang,
• Xin Zhao,
• Yang Liu and
• Wenjun Zhou

Beilstein J. Nanotechnol. 2022, 13, 298–312, doi:10.3762/bjnano.13.25

• Yiru Wang Xin Zhao Yang Liu Wenjun Zhou School of Mechanical Engineering, Chengdu University, Chengdu 610100, China Institute for Advanced Study, Chengdu University, Chengdu, 610106, PR China Officers College of PAP, Chengdu, 610213, China School of Chemistry and Chemical Engineering, Neijiang

• can replace non-renewable resources such as coal and oil [3]. In order to convert mechanical energy into electrical energy, various methods were developed, such as electromagnetic generators [4][5][6], piezoelectric materials [7][8][9][10], and pyroelectric materials [11][12]. The underlying

• principles of TENGs converting mechanical energy into electrical energy are the friction electrification effect and the electrostatic induction principle. When two materials with different electronegativity are physically contacted, positive and negative electrostatic charges are generated on each material

Effects of drug concentration and PLGA addition on the properties of electrospun ampicillin trihydrate-loaded PLA nanofibers

• Tuğba Eren Böncü and
• Nurten Ozdemir

Beilstein J. Nanotechnol. 2022, 13, 245–254, doi:10.3762/bjnano.13.19

• concentration (4–12%) and addition of PLGA (20–80%) on the spinnability of the solutions, morphology, average nanofiber diameter, encapsulation efficiency, drug release, and mechanical properties of PLA and PLA/PLGA nanofibers were examined. All nanofibers were bead-free and uniform. They had favorable

• encapsulation efficiency (approx. 90%) and mechanical properties. The increase in the amount of ampicillin trihydrate caused an increase in the diameter and burst effect of the nanofibers. The drug release ended on the 7th and 3rd day with nanofibers containing 4% and 12% of drug, respectively. The prolonged

• produced with enhanced encapsulation efficiency and mechanical properties, resulting in controlled and tailored release of ampicillin trihydrate for at least ten days. In conclusion, it was demonstrated that the addition of PLGA in different ratios and the amount of drug can be manipulated to obtain the

Relationship between corrosion and nanoscale friction on a metallic glass

• Haoran Ma and
• Roland Bennewitz

Beilstein J. Nanotechnol. 2022, 13, 236–244, doi:10.3762/bjnano.13.18

• surface dissolution at the interface of the two layers. The findings contribute to the understanding of mechanical contacts with metallic glasses under corrosive conditions by exploring the interrelation of microscopic corrosion mechanisms and nanoscale friction. Keywords: atomic force microscopy (AFM

• ); corrosion; friction; metallic glass; passive film; Introduction Metallic glasses (MGs) exhibit excellent mechanical properties including extraordinary hardness and strength [1][2]. Thus, MGs have emerged as novel wear-resistant materials with high potential in tribological applications [3][4][5][6][7][8

• surface, and the competition between diffusion of hydrates into solution and their precipitation into a growing outer layer. Understanding the mechanisms of nanoscale friction on metallic glasses is a basis for applications involving mechanical contacts under corrosive conditions. Also, nanotribology

Engineered titania nanomaterials in advanced clinical applications

• Padmavati Sahare,
• Paulina Govea Alvarez,
• Juan Manual Sanchez Yanez,
• Gabriel Luna-Bárcenas,
• Samik Chakraborty,
• Sujay Paul and
• Miriam Estevez

Beilstein J. Nanotechnol. 2022, 13, 201–218, doi:10.3762/bjnano.13.15

• , and low toxicity [1]. TiO2 nanomaterials can be applied in a host of applications, including biomedical, optical, electronic, mechanical, and chemical fields, amongst other scenarios [2]. The application of titania nanomaterials in the pharmaceutical field has brought revolutionary changes by

• , proliferation, and differentiation of the osteoblasts. However, the low fracture toughness and brittleness of akermanite have limited its use in load-bearing sites of bone tissue. To strengthen the mechanical properties nanoscale titania (nano-TiO2) was distributed into the ceramic matrix. A remarkable

• improvement in the mechanical properties was observed after the incorporation of 5 wt of nano-TiO2 and a bone-like apatite structure was formed in simulated body fluid (SBF), which supported cell attachment and growth, showing the potential for bone TE applications [73]. Human gingival fibroblasts (HGFs) are

Piezoelectric nanogenerator for bio-mechanical strain measurement

• Zafar Javed,
• Lybah Rafiq,
• Muhammad Anwaar Nazeer,
• Saqib Siddiqui,
• Muhammad Babar Ramzan,
• Muhammad Qamar Khan and
• Muhammad Salman Naeem

Beilstein J. Nanotechnol. 2022, 13, 192–200, doi:10.3762/bjnano.13.14

Theoretical understanding of electronic and mechanical properties of 1T′ transition metal dichalcogenide crystals

• Seyedeh Alieh Kazemi,
• Sadegh Imani Yengejeh,
• Vei Wang,
• William Wen and
• Yun Wang

Beilstein J. Nanotechnol. 2022, 13, 160–171, doi:10.3762/bjnano.13.11

• of layered 1T′ TMD crystals have rarely been studied. As TMD monolayers do not have interlayer interactions, their physicochemical properties will differ from those of layered TMD materials. In this study, the electronic and mechanical characteristics of a range of 1T′ TMDs are systematically

• properties of the monolayers shows that the interlayer van der Waals forces can slightly weaken the TM–X covalent bonding strength, which can further influence the mechanical properties. These insights revealed by our theoretical studies may boost more applications of 1T′ TMD materials. Keywords: 1T

• that the performance of 1T′ TMDs is strongly determined by their electronic and mechanical characteristics [11][12][13][14][15][16][17][18][19][20][21]. A lot of work has been devoted to the understanding of the properties of two-dimensional (2D) TMD monolayers [22][23][24][25][26][27]. Multilayered

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

• recent years. On account of the unique properties such as high surface area, high porosity, mechanical strength, and controllable surface morphologies, electrospun nanofiber membranes have been found to have a great potential in many disciplines. Pure electrospun fiber mats modified with different

• fibers with plenty of exciting properties. The distinctive, exciting properties such as a high surface area to volume ratio, high porosity, interconnected pores, narrow pore size distribution, excellent mechanical, electrical and chemical properties and the tunability of the properties by precise

• bioactive products. Patel et al. fabricated bioactive electrospun nanocomposite scaffolds of poly(lactic acid) for bone tissue engineering by incorporating cellulose nanocrystals and observed that the nanohybrid has excellent properties in terms of mechanical strength and thermal stability compared to the

Nanoscale friction and wear of a polymer coated with graphene

• Robin Vacher and
• Astrid S. de Wijn

Beilstein J. Nanotechnol. 2022, 13, 63–73, doi:10.3762/bjnano.13.4

• the polymer chains and reduces the indentation depth. Keywords: friction; graphene; molecular dynamics; polymer; Introduction Graphene is a two dimensional material that has remarkable properties, both electronic [1][2] and mechanical [3][4]. Even before anything was known about graphene, the

• mechanical properties were already being utilised in engineering applications. Graphite powder, essentially thick flakes of graphene, has been used as a lubricant additive for over a century to reduce wear and friction during sliding [5][6][7]. Nevertheless, we still do not understand the wide variety of

• local frictional heating leading to a change in mechanical properties of the polymer below the tip. In the case of the crumpled graphene sheet (Figure 12), the frictional curve is subject to more fluctuations. The calculation of the average frictional force taken between support displacements of 50 and

Effect of lubricants on the rotational transmission between solid-state gears

• Huang-Hsiang Lin,
• Jonathan Heinze,
• Alexander Croy,
• Rafael Gutiérrez and
• Gianaurelio Cuniberti

Beilstein J. Nanotechnol. 2022, 13, 54–62, doi:10.3762/bjnano.13.3

• Huang-Hsiang Lin Jonathan Heinze Alexander Croy Rafael Gutierrez Gianaurelio Cuniberti Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, Dresden, Germany 10.3762/bjnano.13.3 Abstract Lubricants are widely used in macroscopic mechanical systems to reduce friction

• formation process between gears. Keywords: lubricants; MD simulation; rotational transmission; solid-state gears; Introduction In mechanical systems, lubrication is the most common way to reduce friction and wear [1][2][3][4]. The idea of lubricants is preventing direct contact between surfaces to avoid

• mechanical systems such as nanorobots [28] or mechanical calculators such as the Pascaline [29]. This draws a lot of attention to issues such as triggering rotations on a surface [30][31][32][33][34][35][36][37][38][39][40], collective rotations [41][42][43][44][45][46][47][48] and rotational dissipation [49

Sputtering onto liquids: a critical review

• Anastasiya Sergievskaya,
• Adrien Chauvin and
• Stephanos Konstantinidis

Beilstein J. Nanotechnol. 2022, 13, 10–53, doi:10.3762/bjnano.13.2

• methods are based on physical transformations of matter. These methods mainly operate with a “top-down” strategy where bulk materials are reduced in size, down to the nanoscale, via their interaction with photons, heat, or ions or via mechanical milling. Those methods are valuable as they are free from

Measurement of polarization effects in dual-phase ceria-based oxygen permeation membranes using Kelvin probe force microscopy

• Kerstin Neuhaus,
• Christina Schmidt,
• Liudmila Fischer,
• Wilhelm Albert Meulenberg,
• Ke Ran,
• Joachim Mayer and
• Stefan Baumann

Beilstein J. Nanotechnol. 2021, 12, 1380–1391, doi:10.3762/bjnano.12.102

• temperature range above 800 °C [10][11][12], and microstructural as well as mechanical investigations and optimizations have been performed [13][14][15]. Especially for FeCo2O4 addition, the development of an additional electron-conductive phase (namely (Ce,Gd)(Fe,Co)O3), whose composition and abundance

• environment are the strong decrease in oxygen ion mobility below 600 °C, mechanical stability and chemical stability against the used reactive gases, and local chemical reactions at the triple-phase boundaries (ceria|electron conductor|gas) as well as at the interfaces between the different components (ceria

Alteration of nanomechanical properties of pancreatic cancer cells through anticancer drug treatment revealed by atomic force microscopy

• Xiaoteng Liang,
• Shuai Liu,
• Xiuchao Wang,
• Dan Xia and
• Qiang Li

Beilstein J. Nanotechnol. 2021, 12, 1372–1379, doi:10.3762/bjnano.12.101

• Chemistry of Ministry of Education, And School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, Shandong, China Tianjin Medical University Cancer Institute & Hospital, Tianjin, 300060, China 10.3762/bjnano.12.101 Abstract The mechanical properties of cells are key to the

• regulation of cell activity, and hence to the health level of organisms. Here, the morphology and mechanical properties of normal pancreatic cells (HDPE6-C7) and pancreatic cancer cells (AsPC-1, MIA PaCa-2, BxPC-3) were studied by atomic force microscopy. In addition, the mechanical properties of MIA PaCa-2

• development of early diagnosis methods is of importance. The traditional biological methods to research pancreatic cancer are based on molecular genetics and gene signaling. However, the mechanical properties of cells, which can enable cells to express various biological functions have been ignored [4

Polarity in cuticular ridge development and insect attachment on leaf surfaces of Schismatoglottis calyptrata (Araceae)

• Venkata A. Surapaneni,
• Tobias Aust,
• Thomas Speck and
• Marc Thielen

Beilstein J. Nanotechnol. 2021, 12, 1326–1338, doi:10.3762/bjnano.12.98

• reducing the frictional forces experienced when they walk on the leaves and might also provide mechanical stability to the growing plant organs. Here, we have studied the development of cuticular ridges on adaxial leaf surfaces of the tropical Araceae Schismatoglottis calyptrata. We used polymer replicas

• mechanical stability to the growing organs by possibly avoiding cuticle cracking and maintaining structural integrity during rapid leaf area expansion [13][14]. Recently, a study of 75 different eudicot species has shown that their leaf growth is polar (or direction-dependent) and diverse and has identified

• ][18][19][20][21]. One aspect that would be interesting to know is whether cuticular structures such as ridges also display such polarity during growth in the proximodistal or mediolateral axes. This is the focus of the present study. Such knowledge will help in understanding the mechanical basis of

Cantilever signature of tip detachment during contact resonance AFM

• Devin Kalafut,
• Ryan Wagner,
• Maria Jose Cadena,
• Anil Bajaj and
• Arvind Raman

Beilstein J. Nanotechnol. 2021, 12, 1286–1296, doi:10.3762/bjnano.12.96

• Devin Kalafut Ryan Wagner Maria Jose Cadena Anil Bajaj Arvind Raman School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA 10.3762/bjnano.12.96 Abstract Contact resonance atomic force microscopy, piezoresponse force microscopy, and electrochemical strain microscopy are

• methods provide information on important mechanical and electrical properties across a wide variety of samples. CR-AFM, PFM, and ESM are built upon the fundamental assumption that as the cantilever is excited, the probe tip remains in contact with the sample. Signal-to-noise ratios in these measurements

Enhancement of the piezoelectric coefficient in PVDF-TrFe/CoFe₂O₄ nanocomposites through DC magnetic poling

• Marco Fortunato,
• Alessio Tamburrano,
• Maria Paola Bracciale,
• Maria Laura Santarelli and
• Maria Sabrina Sarto

Beilstein J. Nanotechnol. 2021, 12, 1262–1270, doi:10.3762/bjnano.12.93

• poling; piezoelectric effect; piezoresponse force microscopy (PFM); poly(vinylidene fluoride-co-trifluoroethylene); PVDF-TrFe; PVDF-TrFe nanocomposites; Introduction In the last years, innovative energy harvesting systems based on the piezoelectric effect, able to convert vibrational mechanical energy

• piezoelectric and ferroelectric properties, high chemical resistance, high thermal stability, large polarization, short switching time, and mechanical flexibility. All these combined characteristics make it suitable for a wide range of advanced applications, from sensing to energy harvesting [8][9][10][11]. It

• fluoride-co-trifluoroethylene) (PVDF-TrFE) [15][16][17]. This copolymer shows a higher piezoelectric coefficient than PVDF, while still maintaining a high flexibility, sensitivity, and mechanical durability. It is also, like PVDF, a biocompatible polymer. In order to obtain the best piezoelectric response

Electrical, electrochemical and structural studies of a chlorine-derived ionic liquid-based polymer gel electrolyte

• Ashish Gupta,
• Amrita Jain,
• Manju Kumari and
• Santosh K. Tripathi

Beilstein J. Nanotechnol. 2021, 12, 1252–1261, doi:10.3762/bjnano.12.92

• in the polymer which assists in the rapid ion motion while keeping its mechanical stability. The second aim is to increase the ionic conductivity of the electrolytes, which is generally insufficient for practical applications in electrochemical energy storage devices. Hence, different kinds of

• predominantly crystalline PVdF phase and an amorphous HFP phase, which provides necessary mechanical strength and good ion transport matrix. Magnesium-based electrochemical devices are emerging as an alternative to lithium-based devices [26][27][28][29][30]. Magnesium can be an alternative due to its

• polymer system. Along with the ionic liquid, magnesium salt was also used to prepare the final polymer films. The prepared films possess good dimensional and mechanical stability with acceptable parameters. Impedance spectroscopic studies confirmed that there is an increase in the room-temperature ionic