Enhancing mechanical properties of chitosan/PVA electrospun nanofibers: a comprehensive review

• Nur Areisman Mohd Salleh,
• Amalina Muhammad Afifi,
• Fathiah Mohamed Zuki and
• Hanna Sofia SalehHudin

Beilstein J. Nanotechnol. 2025, 16, 286–307, doi:10.3762/bjnano.16.22

• current techniques and methods for improving the mechanical properties of electrospun nanofibers, thereby enhancing their application in various fields. Materials composition Chitosan is an intriguing material derived from chitin. Because of its promising properties, it has attracted significant attention

Orientation-dependent photonic bandgaps in gold-dust weevil scales and their titania bioreplicates

• Norma Salvadores Farran,
• Limin Wang,
• Primoz Pirih and
• Bodo D. Wilts

Beilstein J. Nanotechnol. 2025, 16, 1–10, doi:10.3762/bjnano.16.1

• 10.3762/bjnano.16.1 Abstract The scales of the gold-dust weevil Hypomeces squamosus are green because of three-dimensional diamond-type chitin–air photonic crystals with an average periodicity of about 430 nm and a chitin fill fraction of about 0.44. A single scale usually contains one to three

• prohibited, is generally not possible with biological photonic crystals, as the refractive index contrast (approx. 1.55) between chitin and air is too low to achieve this condition [4][5]. The intriguing properties of photonic bandgap materials extend beyond coloration, as they can be used for manipulating

• scales are composed of chitin and an undetermined short-wavelength absorbing pigment. To investigate whether the origin of the coloration is structural, we examined the external and internal structure of intact and plasma-etched elytral scales using scanning electron microscopy (Figure 2). Using a

Ultrablack color in velvet ant cuticle

• Vinicius Marques Lopez,
• Wencke Krings,
• Juliana Reis Machado,
• Stanislav Gorb and
• Rhainer Guillermo-Ferreira

Beilstein J. Nanotechnol. 2024, 15, 1554–1565, doi:10.3762/bjnano.15.122

• resilin [18]. Insect cuticle with protein-dominated regions, which can include resilin, an elastic protein present in arthropod cuticles, or unsclerotized chitin exhibits autofluorescence when excited with a laser of 405 nm wavelength. Regions with a low degree or high degree of sclerotization emit

• longitudinal absorptive bands. These are often rods of chitin embedded in a protein matrix [23]. The authors also suggested that there is a proteinaceous filling material, which tends to leach out during preparation of the specimens for SEM, leaving behind empty lacunae. Modelled reflectance of V. orientalis

• on top of each other (E and F). There are also dark transverse bands that interconnect two consecutive longitudinal bands of the same lamellae (arrow), or of two separate lamellae (A and B). Legend: L = lamellae; P = pillars; R = rugosity of chitin fibers embedded in a protein matrix. Scale bars: 100

Functional morphology of cleaning devices in the damselfly Ischnura elegans (Odonata, Coenagrionidae)

• Silvana Piersanti,
• Gianandrea Salerno,
• Wencke Krings,
• Stanislav Gorb and
• Manuela Rebora

Beilstein J. Nanotechnol. 2024, 15, 1260–1272, doi:10.3762/bjnano.15.102

• flexible because of the lower degree of sclerotization, and (3) blue areas are rubber-like with a relatively high proportion of resilin-like proteins or unsclerotized chitin. This method has already been widely applied in the literature [37][38][39][40]. The insects to be observed were frozen in a

• hair to the cuticular lamina (Figure 2a,b). The flag-shaped grooming devices are set in a very soft socket, which appears blue, thus indicating a higher amount of resilin or unsclerotized chitin (Figure 2a). The base of the flag is very sclerotized in its basal portion appearing red and yellow, but

• tends to become richer in resilin or is unsclerotized in its apical portion, where more blue autofluorescence signal is visible (Figure 2a). The cuticular lamina appears blue, thus exhibiting large proportions of resilin or unsclerotized chitin (Figure 2b). Grooming behavior The grooming of damselfly

Functional fibrillar interfaces: Biological hair as inspiration across scales

• Guillermo J. Amador,
• Brett Klaassen van Oorschot,
• Caiying Liao,
• Jianing Wu and
• Da Wei

Beilstein J. Nanotechnol. 2024, 15, 664–677, doi:10.3762/bjnano.15.55

• underwater to generate adhesion [51]. Mechanical protection While hairs provide protection via their thermal and chemical properties, they also offer protection based on their mechanical properties. Hairs are typically made of stiff materials, such as keratin and chitin, that have Young’s moduli of the order

The origin of black and white coloration of the Asian tiger mosquito Aedes albopictus (Diptera: Culicidae)

• Manuela Rebora,
• Gianandrea Salerno,
• Silvana Piersanti,
• Alexander Kovalev and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2023, 14, 496–508, doi:10.3762/bjnano.14.41

• only in dry specimens under reflected light, while the white scales observed under transmitted light appear transparent. Moreover, the white scales immersed in oil with a refractive index close that of chitin do not appear white, but rather transparent, while the black scales appear dark due to the

• , which modulates the reflection spectra. Its contribution is about 11% (considering the refractive index of chitin of 1.56 and an illumination angle of 45°), and it is visible as faint colours on the white background in microscopic observations (Figure 5a). A similar but weaker interference is present in

• enhance this effect. Collective effects of the overlapping scales Finally, the fact that the scales overlap each other (Figure 5d) may lead to an increase of both reflection and scattering. Thus, the specular reflection from four overlapping chitin scales at 45° should be three times stronger than the

Interaction between honeybee mandibles and propolis

• Leonie Saccardi,
• Franz Brümmer,
• Jonas Schiebl,
• Oliver Schwarz,
• Alexander Kovalev and
• Stanislav Gorb

Beilstein J. Nanotechnol. 2022, 13, 958–974, doi:10.3762/bjnano.13.84

• mandibles is particularly strong due to bonding of long chitin chains and sclerotization (crosslinking of proteins in the cuticle) [6]. Foraging and handling of propolis Worker bees exhibit a division of labour based on age (polyethism) [9] in which duties such as brood rearing are usually performed by

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

• changes in the interaction of water molecules with the chitin of the cuticle after rehydration. Insect cuticle is a biological composite with a protein matrix and embedded chitin fibers [17]. It is the only biological composite that has been modelled successfully using the modified Voigt estimate of the

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

• , modified chitin, cellulose acetate (CA) and chitosan (CS) have been electrospun as nanohybrids and have been used in a variety of applications [7][8]. Regarding the health sector, the enhanced biocompatibility, antibacterial properties, and cell compatibility has made ENHs great candidates to deliver

• achieved. The membrane also showed antifouling properties and was reusable for several dye removing cycles [77]. Furthermore, Gopi and co-workers reported a PVDF electrospun nanomembrane functionalized with chitin nanowhiskers (ChNW) using a needleless electrospinning technique. ChNW transforms the

The role of deep eutectic solvents and carrageenan in synthesizing biocompatible anisotropic metal nanoparticles

• Nabojit Das,
• Akash Kumar and
• Raja Gopal Rayavarapu

Beilstein J. Nanotechnol. 2021, 12, 924–938, doi:10.3762/bjnano.12.69

• for dissolving many species of high polarity, for example, amino acids, metal salts, glycerol, benzoic acid, citric acid, and glucose [26][76]. They are also promising in the dissolution of different polymers, such as starch, cellulose, lignin, chitin, and are also used in the pre-treatment of

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

Mapping the local dielectric constant of a biological nanostructured system

• Wescley Walison Valeriano,
• Rodrigo Ribeiro Andrade,
• Juan Pablo Vasco,
• Angelo Malachias,
• Bernardo Ruegger Almeida Neves,
• Paulo Sergio Soares Guimarães and
• Wagner Nunes Rodrigues

Beilstein J. Nanotechnol. 2021, 12, 139–150, doi:10.3762/bjnano.12.11

• ion mass spectrometry (TOF-SIMS), Carr et al. [18] concluded that the wing layers consist of mostly chitin with an alternating content of melanin. Chitin forms the structure and melanin modulates the relative permittivity along the cross section. From the results shown in Figure 7, we can see that, in

• the crystal. The Lyddane–Sachs–Teller relation has been extended to other crystalline systems and disordered materials [24][25][26] but its application for the present case, chitin with a varying concentration of melanin, is not straightforward. There is a direct relation between the refractive index

• obtained with the refraction index profiles shown on the left. According to the results shown in Figure 8, the refraction index along the cross section of the damselfly wings varies from 1.52 ± 0.02 to 1.72 ± 0.02. The layers are essentially composed of chitin with varying melanin concentration from layer

Antimicrobial metal-based nanoparticles: a review on their synthesis, types and antimicrobial action

• Matías Guerrero Correa,
• Fernanda B. Martínez,
• Cristian Patiño Vidal,
• Camilo Streitt,
• Juan Escrig and
• Carol Lopez de Dicastillo

Beilstein J. Nanotechnol. 2020, 11, 1450–1469, doi:10.3762/bjnano.11.129

• protection to the cell against osmotic rupture and mechanical damage. It is the first barrier against any harmful particles from the environment, such as oxidative molecules. Every type of microorganism has a different cell wall composition: i) fungi and yeast are mainly composed of chitin and

Biocatalytic oligomerization-induced self-assembly of crystalline cellulose oligomers into nanoribbon networks assisted by organic solvents

• Yuuki Hata,
• Yuka Fukaya,
• Toshiki Sawada,
• Masahito Nishiura and
• Takeshi Serizawa

Beilstein J. Nanotechnol. 2019, 10, 1778–1788, doi:10.3762/bjnano.10.173

• nanoarchitectonics [1][4][11]. Achievements include nanopatterning [12], drug delivery [13], molecular sensing [14], nanodevices [15][16], and cell architectures [17][18]. On the other hand, crystalline poly- and oligosaccharides, such as cellulose and chitin, lag behind in nanoarchitectonics despite the superiority

Scavenging of reactive oxygen species by phenolic compound-modified maghemite nanoparticles

• Małgorzata Świętek,
• Yi-Chin Lu,
• Rafał Konefał,
• Liliana P. Ferreira,
• M. Margarida Cruz,
• Yunn-Hwa Ma and
• Daniel Horák

Beilstein J. Nanotechnol. 2019, 10, 1073–1088, doi:10.3762/bjnano.10.108

• ][10][11]. To enhance the antioxidant properties of inorganic particles, they should be surface-modified with antioxidants or antioxidant-modified polymers. These types of polymers include chitosan, which is a product of chitin deacetylation and is composed of D-glucosamine and N-acetyl-D-glucosamine

Biomimetic synthesis of Ag-coated glasswing butterfly arrays as ultra-sensitive SERS substrates for efficient trace detection of pesticides

• Guochao Shi,
• Mingli Wang,
• Yanying Zhu,
• Yuhong Wang,
• Xiaoya Yan,
• Xin Sun,
• Haijun Xu and
• Wanli Ma

Beilstein J. Nanotechnol. 2019, 10, 578–588, doi:10.3762/bjnano.10.59

• hybrids (Ag-G.b.) by magnetron sputtering technology. The 3D surface-enhanced Raman scattering (SERS) substrate is fabricated from an original chitin-based nanostructure, which serves as a bio-scaffold for Ag nanofilms to be coated on. The novel crisscrossing plate-like nanostructures of 3D Ag-G.b

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

• building materials with 0.5 µm to 1 mm thickness [212]. Additionally, the insect wings are formed by a complex vein system which gives superior stability to the entire wing structure [213][214][215]. Long chain crystalline chitin polymer is the basic framework of insect wings that provides membrane support

Bioinspired self-healing materials: lessons from nature

• Joseph C. Cremaldi and
• Bharat Bhushan

Beilstein J. Nanotechnol. 2018, 9, 907–935, doi:10.3762/bjnano.9.85

• typically from chitin, cuticle (a chitin–protein composite material), or calcium carbonate [67]. Figure 5A shows the various layers that compose the epidermis and exoskeleton [68]. Secretion of exoskeletal material adds to the exoskeleton’s thickness, growing the exoskeleton from within [26]. This very

Liquid-crystalline nanoarchitectures for tissue engineering

• Baeckkyoung Sung and
• Min-Ho Kim

Beilstein J. Nanotechnol. 2018, 9, 205–215, doi:10.3762/bjnano.9.22

• DNA, collagen, chitin, viruses, as well as phospholipids and cellulose [23][24]. In test tubes, biocolloidal systems can be finely tuned to form self-organized structures by complex interplays between entropic and enthalpic driving forces, electrostatic and viscoelastic effects, and hydrophilic and

• [36] and drug delivery systems [37]. For tissue regeneration, the mostly studied biomaterials are collagen and chitin, which are, respectively, protein-based and glucose-based biopolymers [38][39]. When denatured, collagen and chitin can be transformed into gelatin and chitosan, respectively, which

• cholesteric droplets of concentrated suspensions of α-chitin and chitosan have been reported [45], and nematic order was also confirmed in the solutions of collagen type IV [46]. Similarly, the cholesteric phase behavior of cellulose fibrils is well established. For all these cases, the isotropic–nematic

Development of polycationic amphiphilic cyclodextrin nanoparticles for anticancer drug delivery

• Gamze Varan,
• Juan M. Benito,
• Carmen Ortiz Mellet and
• Erem Bilensoy

Beilstein J. Nanotechnol. 2017, 8, 1457–1468, doi:10.3762/bjnano.8.145

• bioactive cationic polysaccharide derived from deacetylation of chitin and is well-characterized for its mucosal penetration enhancer property and apoptotic activity against cancer cells [42]. To alter the surface charge of nanomaterials, chitosan can be used as coating material in nanoparticles [43][44

Cationic PEGylated polycaprolactone nanoparticles carrying post-operation docetaxel for glioma treatment

• Cem Varan and
• Erem Bilensoy

Beilstein J. Nanotechnol. 2017, 8, 1446–1456, doi:10.3762/bjnano.8.144

• polymer with optimal results. CS, which is produced commercially by deacetylation of chitin, is a linear polysaccharide. It is a biocompatible and nontoxic natural polymer [33][34][35][36][37][38][39] which is known to act as a penetration enhancer, mucoadhesive [40], antitumor [41] and immune-adjuvant

Biological and biomimetic materials and surfaces

• Stanislav Gorb and
• Thomas Speck

Beilstein J. Nanotechnol. 2017, 8, 403–407, doi:10.3762/bjnano.8.42

• siliceous teeth consist of composite materials with silica-based cap-like structures situated on chitin-bearing cuticle sockets that are connected through flexible resilient areas containing resilin protein. This composite architecture contributes to the performance of the siliceous teeth in damaging

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

• . Additional examples for materials are listed in Table 1 and in some other review articles [4][5][46][47][71][86][87] Polymers from natural sources can be divided in either protein-based (e.g., collagen, fibrin, matrigel, elastin), polysaccharide-based (e.g., hyaluronic acid, chitin, agar, dextran, alginate

Functional diversity of resilin in Arthropoda

• Jan Michels,
• Esther Appel and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1241–1259, doi:10.3762/bjnano.7.115

• chitin fibres. In the last decades, numerous exoskeleton structures with large proportions of resilin and various resilin functions have been described. Today, resilin is known to be responsible for the generation of deformability and flexibility in membrane and joint systems, the storage of elastic

• assumed. The properties of resilin-containing exoskeletons can strongly differ between structures and organisms. The reason is that in biological structures resilin seems to be rarely present in pure or nearly pure form but is known to commonly exist together with other proteins and/or chitin fibres in

• , which can be tested with a number of methods [5]. Resilin is colourless, transparent and amorphous. Accordingly, structures with very large resilin proportions can be easily distinguished from structures with relatively large proportions of chitin that are typically pigmented and only slightly

Green and energy-efficient methods for the production of metallic nanoparticles

• Mitra Naghdi,
• Mehrdad Taheran,
• Satinder K. Brar,
• M. Verma,
• R. Y. Surampalli and
• J. R. Valero

Beilstein J. Nanotechnol. 2015, 6, 2354–2376, doi:10.3762/bjnano.6.243

• reaction medium [104]. Renewable feedstock: Increasing the share of renewable sources either for raw material and energy are very important. The largest renewable source for energy is biomass [129]. There are also many examples for using renewable material in synthesis of NPs including cellulose, chitin