Microneedle-based ocular drug delivery systems – recent advances and challenges

• Piotr Gadziński,
• Anna Froelich,
• Monika Wojtyłko,
• Antoni Białek,
• Julia Krysztofiak and
• Tomasz Osmałek

Beilstein J. Nanotechnol. 2022, 13, 1167–1184, doi:10.3762/bjnano.13.98

• sclera, a membrane composed of randomly scattered collagen fibers, ranges from 0.5 to 1 mm, depending on the region of occurrence [41]. While the sclera is another barrier preventing drug permeation, the choroid is responsible for drug elimination. The blood–retinal barrier is connected to the retinal

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

• ]. Review Bone structure Bone is a hard tissue that contains different kinds of cells including osteoblasts, osteocytes, and osteoclasts (Figure 1) [26]. The inorganic hydroxyapatite and organic type I collagen components are vital to bone tissue. The bone biomineralisation activities are formed by

• nanosized hydroxyapatite crystals with connective collagen fibrils [27]. The bone possesses a unique combination of strength and stiffness, and it has excellent compressive strength and tensile strength due to the attribution of deep nanostructures of inorganic and organic components. Human bones are

• matrix structure (cancellous interior) [30]. Also, the mechanical properties of cancellous bones are controlled by the structural organization of the matrix [31]. The bone microstructure mainly comprises collagen threads of lamellae coiled around layers to form a 200–250 µm diameter osteon which can vary

Bioselectivity of silk protein-based materials and their bio-inspired applications

• Hendrik Bargel,
• Vanessa T. Trossmann,
• Christoph Sommer and
• Thomas Scheibel

Beilstein J. Nanotechnol. 2022, 13, 902–921, doi:10.3762/bjnano.13.81

• interacting with members of the integrin family of cell surface proteins. However, fibronectin is a multifunctional adhesion molecule, also binding to other protein constituents of the ECM such as fibrin, collagen, and heparin [24]. Thus, fibronectin is involved in several physiological events such as

• from the development of sophisticated synthetic polymer systems [26][27], protein-based and bioinspired materials have nowadays an enormous impact [28][29]. Biomaterials based on native collagen, keratin, elastin, silk, and their recombinant, engineered counterparts become increasingly popular in

• bioadhesiveness of a material is the tripeptide RGD, naturally occurring in various ECM proteins including fibronectin, vitronectin, laminin, and collagen [34][35][37][38][39][40][41]. This frequently used peptide has been shown to increase the bioadhesiveness of biomaterials by interacting with cellular integrin

Gelatin nanoparticles with tunable mechanical properties: effect of crosslinking time and loading

• Agnes-Valencia Weiss,
• Daniel Schorr,
• Julia K. Metz,
• Metin Yildirim,
• Saeed Ahmad Khan and
• Marc Schneider

Beilstein J. Nanotechnol. 2022, 13, 778–787, doi:10.3762/bjnano.13.68

• (10.000 µg/mL), Gibco™, Fisher Scientific, Waltham, MA, USA). All plastic devices used for hAELVi culture were precoated with a 1% v/v fibronectin (Corning, NY, USA)–collagen (Sigma-Aldrich, Darmstadt, Germany) solution. Methods Preparation of gelatin nanoparticles The preparation was based on the

Effects of substrate stiffness on the viscoelasticity and migration of prostate cancer cells examined by atomic force microscopy

• Xiaoqiong Tang,
• Yan Zhang,
• Jiangbing Mao,
• Yuhua Wang,
• Zhenghong Zhang,
• Zhengchao Wang and
• Hongqin Yang

Beilstein J. Nanotechnol. 2022, 13, 560–569, doi:10.3762/bjnano.13.47

• sterile water, and stored at 4 °C. The stiffness of the hydrogels with different proportions were shown in Table 1. Next, the gels were coated with a sulfo-SANPAH solution and activated in UV light at 365 nm for 10 min. These gels were then coated with type I collagen (0.1 mg·mL−1) and incubated overnight

• at 4 °C. On the second day, the excess collagen solution was removed with sterile water, and then HPV-PZ-7 and PC-3 cells were inoculated onto PPA substrates with different stiffness for 12, 24, 48, and 72 h. The schematic diagram regarding this process is shown in Figure 1a. Cell death assay Cells

Ciprofloxacin-loaded dissolving polymeric microneedles as a potential therapeutic for the treatment of S. aureus skin infections

• Sharif Abdelghany,
• Walhan Alshaer,
• Yazan Al Thaher,
• Maram Al Fawares,
• Amal G. Al-Bakri,
• Saja Zuriekat and
• Randa SH. Mansour

Beilstein J. Nanotechnol. 2022, 13, 517–527, doi:10.3762/bjnano.13.43

• generally less than 10–80 µm. Microneedles that can reach deeper than 80 µm can potentially deliver the incorporated drug for the treatment of local and systemic infections [55]. The dermis is a viable layer that is rich in water, blood capillaries, and connective tissues including collagen and elastin [56

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

• responsible for the elasticity and resistance of the skin in the dermis, (i.e., the middle layer of the skin) are collagen and elastin, and the changes in these two components play an important role in the skin aging process [1][2]. The production of reactive oxygen species (ROS) or free radicals through

• ultraviolet (UV) radiation, smoking, pollution, and normal endogenous metabolic processes triggers the skin aging process. Elastase and collagenase enzymes induced by the formation of ROS accelerate the aging process and cause loss of collagen and elastin fibrils. With the formation of free radicals, lipid

• by UV radiation was investigated. The inhibitory effect on MMP-2 and MMP-9 enzymes, which are responsible for the degradation of type IV and type VII collagen, respectively, was measured in HaCaT cells, and a higher inhibition of MMP enzymes was achieved with higher penetration against unformulated

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

• responsible for the synthesis and maintenance of hyaline cartilage matrix [8]. Chondrocytes are embedded in a dense ECM composed mainly of water, glycosaminoglycans (GAGs), and collagen fibers. Collagen comprises 60–85% of adult articular cartilage and has a fibrous structure, which extensively contributes to

• 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

• 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

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

• the main connective tissue cells that secrete the collagen-rich extracellular matrix (ECM) for generating soft tissues that bind with the implants. Wang and co-workers reported that the super hydrophilic nanotubular structure of hydrogenated TiO2 prepared by anodic oxidation and thermal hydrogenation

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

• . demonstrated enhanced proliferation and chondrogenic differentiation of human mesenchymal stem cells by applying lipid-coated MBs plus low-intensity pulsed US. After treatment, cell proliferation was increased by 40%, and the production of glycosaminoglycan and type II collagen was increased by 17% and 78

The nanomorphology of cell surfaces of adhered osteoblasts

• Christian Voelkner,
• Mirco Wendt,
• Regina Lange,
• Max Ulbrich,
• Martina Gruening,
• Susanne Staehlke,
• Barbara Nebe,
• Ingo Barke and
• Sylvia Speller

Beilstein J. Nanotechnol. 2021, 12, 242–256, doi:10.3762/bjnano.12.20

• the initial phase of adhesion well before the release of matrix vesicles in the collagen matrix. Our results include characteristic sheet-like protrusions, so-called ruffles. Their appearance on the osteoblast cell rims mostly vanishes when a large adhesion area is established, resulting in a smooth

Bio-imaging with the helium-ion microscope: A review

• Matthias Schmidt,
• James M. Byrne and
• Ilari J. Maasilta

Beilstein J. Nanotechnol. 2021, 12, 1–23, doi:10.3762/bjnano.12.1

• particularly powerful for imaging the three-dimensional articular cartilage collagen networks at a resolution of down to 0.81 nm (Figure 5). Another application benefiting from the large depth of field and the possibility to work without coating the sample with metal is the use of HIM for the investigation of

Triboelectric nanogenerator based on Teflon/vitamin B1 powder for self-powered humidity sensing

• Liangyi Zhang,
• Huan Li,
• Yiyuan Xie,
• Jing Guo and
• Zhiyuan Zhu

Beilstein J. Nanotechnol. 2020, 11, 1394–1401, doi:10.3762/bjnano.11.123

• -free humidity sensors by using biocompatible collagen nanofibrils [43]. More recently, Zhang et al. developed a TENG-driven self-powered flexible humidity sensor based on a tin disulfide nanoflower/reduced graphene oxide (SnS2/rGO) hybrid nanomaterial [44]. However, the large-scale application of TENGs

• the TVB-TENG is shown in Figure 5b. Table 1 presents the humidity-sensing characteristics of the proposed humidity sensor in comparison with previously published studies [42][43][44][48][49]. The response and measurement range of the manufactured sensor are comparable to the sensor made from collagen

Wet-spinning of magneto-responsive helical chitosan microfibers

• Dorothea Brüggemann,
• Johanna Michel,
• Naiana Suter,
• Matheus Grande de Aguiar and
• Michael Maas

Beilstein J. Nanotechnol. 2020, 11, 991–999, doi:10.3762/bjnano.11.83

• of nanometers to a few micrometers [21]. Blends of chitosan with alginate, silk, fibroin, cellulose or collagen can also be processed into composite fibers by electrospinning [22]. Wet-spinning is another well-established method of fabricating chitosan fibers with a diameter in the micrometer range

Identification of physicochemical properties that modulate nanoparticle aggregation in blood

• Ludovica Soddu,
• Duong N. Trinh,
• Eimear Dunne,
• Dermot Kenny,
• Giorgia Bernardini,
• Ida Kokalari,
• Arianna Marucco,
• Marco P. Monopoli and
• Ivana Fenoglio

Beilstein J. Nanotechnol. 2020, 11, 550–567, doi:10.3762/bjnano.11.44

• aggregation was monitored by light transmission aggregometry (LTA) in a Chronolog-490D aggregometer (CHRONO-LOG® Corporation, Havertown, PA). Adenosine diphosphate (ADP) and collagen were used as activators of platelet aggregation. The NPs were first suspended in phosphate buffered saline (PBS) and then they

• of CNP-L the concentration was lower to avoid interference (7.25 × 10−5 m2/mL). 2.5 μL of 10 μM ADP or 12.5 μL of 10 μM collagen was then added and aggregation was monitored for 5 min with the suspension continuously stirred. The optical density was also measured for NPs suspended in PRP in the

• observed for all concentrations of plasma tested. Platelet aggregation The effect of the NPs on platelet aggregation was measured using LTA. The NPs were added to platelet-rich plasma (PRP) in the absence or presence of two platelet activators, collagen and ADP. In Figure 9a,b, we show the percent of

Facile biogenic fabrication of hydroxyapatite nanorods using cuttlefish bone and their bactericidal and biocompatibility study

• Satheeshkumar Balu,
• Manisha Vidyavathy Sundaradoss,
• Swetha Andra and
• Jaison Jeevanandam

Beilstein J. Nanotechnol. 2020, 11, 285–295, doi:10.3762/bjnano.11.21

• after annealing which may be due to the removal of organic products such as collagen and protein. Chemicals and reagents Marine waste cuttlefish bones were collected as a source of calcium from Kasimedu fish market, which is located in Chennai, Tamil Nadu, India. All chemicals used for this study were

Lipid nanostructures for antioxidant delivery: a comparative preformulation study

• Elisabetta Esposito,
• Maddalena Sguizzato,
• Markus Drechsler,
• Paolo Mariani,
• Federica Carducci,
• Claudio Nastruzzi,
• Giuseppe Valacchi and
• Rita Cortesi

Beilstein J. Nanotechnol. 2019, 10, 1789–1801, doi:10.3762/bjnano.10.174

• oxidative stress [7]. The release of reactive oxygen species from tobacco smoke provokes a series of systemic immunomodulatory effects that leads to a compromised inflammatory response. These destructive mechanisms also affect collagen synthesis and the skin cellular reparative effects [8][9]. It has been

Serum type and concentration both affect the protein-corona composition of PLGA nanoparticles

• Katrin Partikel,
• Robin Korte,
• Dennis Mulac,
• Hans-Ulrich Humpf and
• Klaus Langer

Beilstein J. Nanotechnol. 2019, 10, 1002–1015, doi:10.3762/bjnano.10.101

• Analysis Imaging System (Essen Bioscience, Inc., Michigan, USA) was used. Therefore, 1 × 105 cells/well were seeded into a collagen coated 24-well plate and cultivated under serum-containing conditions as described above. After four days, the medium was replaced by 500 µL serum-free medium containing

Mechanical and thermodynamic properties of Aβ₄₂, Aβ₄₀, and α-synuclein fibrils: a coarse-grained method to complement experimental studies

• Adolfo B. Poma,
• Horacio V. Guzman,
• Mai Suan Li and
• Panagiotis E. Theodorakis

Beilstein J. Nanotechnol. 2019, 10, 500–513, doi:10.3762/bjnano.10.51

• . In the context of mechanical properties of various fibrils, for example, β-amyloids [4][5], cellulose [6] and collagen [7], all-atom models have been used to estimate the elastic moduli based on the response of the system, but mostly approximately. Still, molecular-level methods are necessary to

• the case of collagen fibrils [55], but it still relies on the correct estimation of the fibril diameter. As above, the CG model helps to devise a protocol where simple shear planes can be applied on a set of atoms and the typical response allows, in a straightforward manner, for the calculation of S

• , while for Aβ42 this value is 2.4 GPa. The value YL = 2.3 GPa in the case of α-syn seems to be half way between the values for Aβ40 and Aβ42 fibrils. Moreover, our YL values are close to the experimental values of collagen fibrils equal to 1.9–3.4 GPa [61]. The bottom panels in Figure 4 illustrate the

Targeting strategies for improving the efficacy of nanomedicine in oncology

• Gonzalo Villaverde and
• Alejandro Baeza

Beilstein J. Nanotechnol. 2019, 10, 168–181, doi:10.3762/bjnano.10.16

• into the tumour [12]. Another strong barrier that hampers the efficacy of nanomedicines is the dense extracellular matrix (ECM), which is usually present in many solid tumours. ECM is commonly denser in solid tumours than in healthy tissues due to a higher content in collagen and other structural

Nanoscale characterization of the temporary adhesive of the sea urchin Paracentrotus lividus

• Ana S. Viana and
• Romana Santos

Beilstein J. Nanotechnol. 2018, 9, 2277–2286, doi:10.3762/bjnano.9.212

• demonstrate that the adhesive from the tubules of the sea cucumber Holothuria forskali were made up of long fibres deposited on a homogeneous film. These fibres contain collagen as evidenced by their 70 nm periodicity, while the homogeneous film appears to be made up of globular nanostructures measuring about

The structural and chemical basis of temporary adhesion in the sea star Asterina gibbosa

• Birgit Lengerer,
• Marie Bonneel,
• Mathilde Lefevre,
• Elise Hennebert,
• Philippe Leclère,
• Emmanuel Gosselin,
• Peter Ladurner and
• Patrick Flammang

Beilstein J. Nanotechnol. 2018, 9, 2071–2086, doi:10.3762/bjnano.9.196

• of A. gibbosa was slightly broader than the flexible stem and full of collagenous fibres (Figure 2B). The collagen fibres were arranged in thick bundles and alternated with clusters of secretory gland cells (Figure 2B and Figure 3A). In asteroids, three tube foot morphotypes have been described – i.e

• depths (Figure 3A). In the basal area of the disc, the connective tissue (CT) formed branched septa, enclosing bundles of secretory gland cells (Figure 3B). The connective tissue consisted mainly of collagen fibres, which are bearing the force during attachment (Figure 3C). The collagen fibres were

• disc. Arrow in (C) highlights the collagen fibres of the connective tissue. AC - adhesive gland cell; CI - cilia; CL - cuticular layer; CT - connective tissue; DAC - de-adhesive gland cell; IF - intermediate filaments; MV - microvilli; SC - supportive cell; SEC - sensory cell; SMV - specialized

Defect formation in multiwalled carbon nanotubes under low-energy He and Ne ion irradiation

• Santhana Eswara,
• Jean-Nicolas Audinot,
• Brahime El Adib,
• Maël Guennou,
• Tom Wirtz and
• Patrick Philipp

Beilstein J. Nanotechnol. 2018, 9, 1951–1963, doi:10.3762/bjnano.9.186

• improved mechanical properties which is similar to the one of collagen found in nature [7]. Vacancy formation and interconnections forming between CNTs have also been observed in molecular dynamics (MD) simulations during the irradiation of SWCNTs supported by silica [8]. MD simulations have been used to

Preparation of micro/nanopatterned gelatins crosslinked with genipin for biocompatible dental implants

• Reika Makita,
• Tsukasa Akasaka,
• Seiichi Tamagawa,
• Yasuhiro Yoshida,
• Saori Miyata,
• Hirofumi Miyaji and
• Tsutomu Sugaya

Beilstein J. Nanotechnol. 2018, 9, 1735–1754, doi:10.3762/bjnano.9.165

• : Collagen is a basic component of the periodontium and plays an important role in the function of the periodontal unit. Therefore, coating with collagen/gelatin has been applied to enable dental implants to positively interact with peri-implant tissues. Although the micro/nanoscale topography is an

• important property of the surface of dental implants, smaller collagen/gelatin surface patterns have not been sufficiently developed. Furthermore, only few reports on the behavior of cells on gelatin surfaces with different patterns and sizes exist. In this study, we developed micro/nanometer-scaled gelatin

• natural tooth and periodontium, or their biomimetic equivalents. Collagen is a basic component of the periodontium and plays an important role in the function of the periodontal unit [15]. Bundles of collagen fibers in the periodontal ligament, including Sharpey’s fibers, are vertically arranged from the

Review on nanoparticles and nanostructured materials: history, sources, toxicity and regulations

• Jaison Jeevanandam,
• Ahmed Barhoum,
• Yen S. Chan,
• Alain Dufresne and
• Michael K. Danquah

Beilstein J. Nanotechnol. 2018, 9, 1050–1074, doi:10.3762/bjnano.9.98

• , proteins, antibodies and DNA. A list of nanostructures that exist in the human body is presented in Table 1. Even some works categorize bone as a nanomaterial comprised of hierarchical inorganic nano-hydroxyapatite and organic collagen [243]. Additionally, micro-organisms such as viruses and bacteria are

• with the extracellular matrix (ECM) within the stem cells includes influential stem cell behavior through sources of passive mechanical force. A wide structural protein spectrum and polysaccharides of different length scales with dominating nanometer-sized collagen fibrils strands of 35–60 nm diameter