Nanotechnology-based approaches for the removal of microplastics from wastewater: a comprehensive review

• Nayanathara O Sanjeev,
• Manjunath Singanodi Vallabha and
• Rebekah Rubidha Lisha Rabi

Beilstein J. Nanotechnol. 2025, 16, 1607–1632, doi:10.3762/bjnano.16.114

• leading to mass mortality. Such interactions amplify the ecological consequences of MPs in the environment. Consequently, the ingestion of MPs embedded with contaminants can contribute to the transfer of toxic substances across terrestrial and aquatic food webs [46]. In freshwater ecosystems, MPs can

• the process. The removal of MPs by adsorbents primarily relies on hydrophobic interactions, electrostatic attraction and hydrogen bonding, which are influenced by their surface characteristics. Among various adsorbents, activated carbon and biochar have gained wide attention for treating water

• capabilities due to electrostatic interactions, making them highly effective in capturing MPs. Their fast adsorption kinetics support rapid water purification, and surface modifications can further enhance their performance and selectivity. These membranes are also versatile and applicable in various treatment

Few-photon microwave fields for superconducting transmon-based qudit control

• Irina A. Solovykh,
• Andrey V. Pashchenko,
• Natalya A. Maleeva,
• Nikolay V. Klenov,
• Olga V. Tikhonova and
• Igor I. Soloviev

Beilstein J. Nanotechnol. 2025, 16, 1580–1591, doi:10.3762/bjnano.16.112

• the highest possible excited transmon state with n = k0. An increase in the nonlinearity of the transmons leads to a significant reduction in the period of Rabi oscillations, tR, and the beat frequency, tbeat, as shown in Figure 2a. When nonlinear interactions dominate, high-energy excitations are

Photocatalytic degradation of ofloxacin in water assisted by TiO₂ nanowires on carbon cloth: contributions of H₂O₂ addition and substrate absorbability

• Iram Hussain,
• Lisha Zhang,
• Zhizhen Ye and
• Jin-Ming Wu

Beilstein J. Nanotechnol. 2025, 16, 1567–1579, doi:10.3762/bjnano.16.111

• unsatisfactory interaction with target contaminants diminishes photocatalytic degradation efficiency in water. Here, we present a mild solution method to precipitate anatase TiO2 nanowire arrays, measuring 1.5 μm in thickness, over carbon cloth to ensure substantial interactions with target pollutants and, in

• (pH 2) and highly basic (pH 12) conditions reduce the degradation efficiency, likely due to reduced ROS stability or altered surface interactions. It demonstrates that the carbon cloth-supported TiO2 nanowires are capable of functioning in wastewater with a wide pH range. The active radical species

Modeling magnetic properties of cobalt nanofilms used as a component of spin hybrid superconductor–ferromagnetic structures

• Aleksey Fedotov,
• Olesya Severyukhina,
• Anastasia Salomatina and
• Anatolie Sidorenko

Beilstein J. Nanotechnol. 2025, 16, 1557–1566, doi:10.3762/bjnano.16.110

• ., Dolgoprudny, 141701, Russia 10.3762/bjnano.16.110 Abstract The paper presents a mathematical model for studying the magnetic behavior of atoms, which takes into account spin and interatomic interactions. Two problems were solved by means of mathematical modeling. At the first stage, the problem of modeling a

• the reliability level (i.e., 0.8848). Conclusion The mathematical model considered in this work allows us to investigate the magnetic behavior of a nanoscale system taking into account spin and interatomic interactions. The mathematical model is based on the joint solution of the Langevin and Landau

Transient electronics for sustainability: Emerging technologies and future directions

• Jae-Young Bae,
• Myung-Kyun Choi and
• Seung-Kyun Kang

Beilstein J. Nanotechnol. 2025, 16, 1545–1556, doi:10.3762/bjnano.16.109

• environments, these devices maintain their ability to decompose through interactions with naturally occurring water and enzymes (Figure 1f) [32]. Thus, transient electronics present a compelling vision for sustainable electronics, that is, devices that fulfill their intended function and then seamlessly

Dendrimer-modified carbon nanotubes for the removal and recovery of heavy metal ions from water

• Thao Quynh Ngan Tran,
• Huu Trung Nguyen,
• Subodh Kumar and
• Xuan Thang Cao

Beilstein J. Nanotechnol. 2025, 16, 1522–1532, doi:10.3762/bjnano.16.107

• the CNTs was found to be increased with the successive growth of dendrimers resulting in dense carbon nanotubes. It could be due to the interactions such as hydrogen bonding between the growing number of functional groups on the surface of CNTs because of successive growth of dendrimers. Moreover

• for further adsorption studies. The removal of metal ions (Pb2+ and Cd2+) by dendrimer-functionalized CNTs is primarily governed by physical interactions. However, the nitrogen-rich surface of the poly(amidoamine) (PAMAM) dendrimers offers multiple coordination sites, which might facilitate the

• controlled by chemical interactions rather than physical interactions alone [49][50]. Although the pseudo-second order model is often associated with surface-controlled or chemical interactions, its application does not necessarily confirm chemisorption. In this study, thermodynamic analysis (Supporting

Cross-reactivities in conjugation reactions involving iron oxide nanoparticles

• Shoronia N. Cross,
• Katalin V. Korpany,
• Hanine Zakaria and
• Amy Szuchmacher Blum

Beilstein J. Nanotechnol. 2025, 16, 1504–1521, doi:10.3762/bjnano.16.106

• . Through the judicious use of controls, we demonstrate significant cross-reactivities of amines, thiols, maleimides, and common disulfide reducing agents with surface Fe of IONPs and show how these unwanted interactions can produce false positive results. Without proper controls, these can lead to

• reducing agents with the IONP surface, and how these unwanted interactions can influence the interpretation of conjugation results. We use IONPs capped with 3,4-dihydroxybenzoic acid (IONP-3,4-DHBA) as a platform upon which we can perform common conjugation reactions. 3,4-DHBA (Figure 1a) is a catechol

• presence of amide bonds in IONP-PPA, but not in the EDC-free control, in agreement with the FTIR findings. The N 1s spectra, in contrast, are inconclusive for determining the interactions of the amine group with the IONPs. Together, the FTIR, UV–vis, and XPS evidence suggests successful EDC coupling of PPA

Laser processing in liquids: insights into nanocolloid generation and thin film integration for energy, photonic, and sensing applications

• Akshana Parameswaran Sreekala,
• Pooja Raveendran Nair,
• Jithin Kundalam Kadavath,
• Bindu Krishnan,
• David Avellaneda Avellaneda,
• M. R. Anantharaman and
• Sadasivan Shaji

Beilstein J. Nanotechnol. 2025, 16, 1428–1498, doi:10.3762/bjnano.16.104

• al. [2] in one of the first reviews on laser ablation published in 2004. Their discussion addresses the physicochemical insights into key stages of these processes, including the behavior of the laser target, the formation of the plume, and the initial laser–target interactions. It offers a

• combinatorial library of constituents and interactions [15], understanding of these processes remains insufficient. Yan et al. outline a comprehensive mechanistic scenario of PLAL, highlighting the interactions between photons, liquid molecules, solid targets, and laser-induced particles [8]. The formation

• , and catalysis. However, challenges remain, such as the need for improved productivity, narrower size distributions, and better understanding of the dynamic processes involved in laser interactions with liquid media. 1.5 Laser-induced defect engineering in liquids Laser-based techniques have unlocked

The role of biochar in combating microplastic pollution: a bibliometric analysis in environmental contexts

• Tuan Minh Truong Dang,
• Thao Thu Thi Huynh,
• Guo-Ping Chang-Chien and
• Ha Manh Bui

Beilstein J. Nanotechnol. 2025, 16, 1401–1416, doi:10.3762/bjnano.16.102

• . This underscores the necessity of interdisciplinary research integrating material science, agriculture, and microbiology in biochar–MP–plant interactions. Three primary research trajectories emerge from the keyword analysis: Investigating how different biochar synthesis methods influence

• , enhanced diffusion, surface adsorption, and cation–π electron interactions were observed at 550 °C in Polygonum amphibium L. biochar. However, pyrolysis temperatures above 550 °C led to reduced stability [42]. Similarly, pyrolysis at 700 °C can increase SSA but may degrade oxygen-containing functional

• groups, affecting biochar stability [43]. The goal of modified biochar synthesis is to enhance its wastewater treatment and soil remediation capabilities by improving electrostatic and chemical bonding interactions with MPs, beyond the limitations of physical adsorption governed by specific surface area

Synthesis and antibacterial properties of nanosilver-modified cellulose triacetate membranes for seawater desalination

• Lei Wang,
• Shizhe Li,
• Kexin Xu,
• Wenjun Li,
• Ying Li and
• Gang Liu

Beilstein J. Nanotechnol. 2025, 16, 1380–1391, doi:10.3762/bjnano.16.100

• surface properties, and quantum effects, collectively enhance their antimicrobial efficacy [17]. The high surface area-to-volume ratio of nanomaterials facilitates efficient interactions with microorganisms, thereby enhancing their antimicrobial efficacy [18]. Additionally, the surface properties of

• the C/O ratio of the PCTA film. This decrease in the C/O ratio is likely attributed to hydrogen bonding interactions between the –OH groups in Ag(NH3)2OH and the PDA layer. These interactions enhance the oxygen content relative to carbon, thereby reducing the C/O ratio. Collectively, these results

• , evidenced by a pronounced inhibitory ring. Notably, bacteria surrounding the Ag@PCTA membrane are unable to grow, indicating the membrane’s potent antibacterial activity. The antibacterial activity of Ag ions was attributed to their interactions with S-, O-, and N-containing groups in the bacteria [48]. Dai

Enhancing the therapeutical potential of metalloantibiotics using nano-based delivery systems

• Alejandro Llamedo,
• Marina Cano,
• Raquel G. Soengas and
• Francisco J. García-Alonso

Beilstein J. Nanotechnol. 2025, 16, 1350–1366, doi:10.3762/bjnano.16.98

• hinder the delivery of sufficient drug concentrations to the infection site [33]. Systemic barriers refer to challenges associated with the pharmacokinetics of antibiotics, such as rapid clearance, nonspecific distribution, and interactions with healthy tissues [35]. These factors are responsible for

• receptors and ligands, as well as the number of interactions necessary to overcome the energy barrier for cellular uptake. Properly balancing these factors ensures efficient binding and internalization of the nanoparticles by the target cells [50][51]. For example, nanoparticles can be engineered to

• modifications prevent rapid uptake by the reticuloendothelial system, prolonging the presence of the drug in the bloodstream and increasing drug levels in the central nervous system [62]. Additionally, functionalizing liposomes with ligands or antibodies can facilitate specific interactions with cell surface

Ferroptosis induction by engineered liposomes for enhanced tumor therapy

• Alireza Ghasempour,
• Mohammad Amin Tokallou,
• Mohammad Reza Naderi Allaf,
• Mohsen Moradi,
• Hamideh Dehghan,
• Mahsa Sedighi,
• Mohammad-Ali Shahbazi and
• Fahimeh Lavi Arab

Beilstein J. Nanotechnol. 2025, 16, 1325–1349, doi:10.3762/bjnano.16.97

• plays a crucial role in determining their stability and interactions with biological systems. EE can be determined by separating the liposomes from the non-encapsulated drug using techniques such as size exclusion chromatography or centrifugation, followed by quantification of the encapsulated drug

• . Other characterization techniques include nuclear magnetic resonance (NMR) spectroscopy to study membrane fluidity and phase transitions, fluorescence spectroscopy for investigating drug–liposome interactions, and capillary electrophoresis to analyze liposome–drug interactions and drug release [110][121

• the liposomes from the free drugs and enables the determination of the EE [110]. CE offers advantages, such as low sample and buffer consumption, short analysis times, and the possibility of investigating interactions between drugs and liposomes directly in the separation capillary [125]. The

Wavelength-dependent correlation of LIPSS periodicity and laser penetration depth in stainless steel

• Nitin Chaudhary,
• Chavan Akash Naik,
• Shilpa Mangalassery,
• Jai Prakash Gautam and
• Sri Ram Gopal Naraharisetty

Beilstein J. Nanotechnol. 2025, 16, 1302–1315, doi:10.3762/bjnano.16.95

• our comprehension of laser–material interactions and hold potential implications for surface engineering and material science applications. Keywords: cross section of LIPSS; high spatial frequency LIPSS (HSFL); laser-induced periodic surface structures (LIPSS); low spatial frequency LIPSS (LSFL

• how metal surfaces respond to incident wavelengths [53][54]. This work advances our comprehension of LIPSS structures and their applications, shedding new light on the interplay between incident wavelengths and surface interactions. The paper concludes by emphasizing the importance of optical

• properties, laser parameters, and material characteristics in determining penetration depth, thereby contributing to the broader understanding of light–material interactions. Materials and Methods Materials A double-sided polished stainless steel surface (SS304) with a thickness of 100 µm was utilized

Better together: biomimetic nanomedicines for high performance tumor therapy

• Imran Shair Mohammad,
• Gizem Kursunluoglu,
• Anup Kumar Patel,
• Hafiz Muhammad Ishaq,
• Cansu Umran Tunc,
• Dilek Kanarya,
• Mubashar Rehman,
• Omer Aydin and
• Yin Lifang

Beilstein J. Nanotechnol. 2025, 16, 1246–1276, doi:10.3762/bjnano.16.92

• surrounding environment, including immunosuppression in T cells via PD-1/PD-L1 axis, recruitment of stem cells via CXCR4/CXCL2 chemokine axis, maturation of immune cells via membrane interactions, and various other physical/chemical interactions, uncover the emergence of cell membrane-based drug delivery

• tracking and profound interactions within complex biological environments can be achieved by using biomimetic NPs with prolonged circulation time, summarized in Figure 1. Moreover, research in NP-mediated drug delivery has been shifted to focus on the use of cell-derived cancer therapies/engineered or live

• with a specific focus on their types and recent advancements only for cancer treatment. This review focuses on the recent advancements in biomimetic nanomedicines engineered with various biomaterials, emphasizing their interactions with different types of tumors and tumor microenvironment (TME). It

Functional bio-packaging enhanced with nanocellulose from rice straw and cinnamon essential oil Pickering emulsion for fruit preservation

• Tuyen B. Ly,
• Duong D. T. Nguyen,
• Hieu D. Nguyen,
• Yen T. H. Nguyen,
• Bup T. A. Bui,
• Kien A. Le and
• Phung K. Le

Beilstein J. Nanotechnol. 2025, 16, 1234–1245, doi:10.3762/bjnano.16.91

• characteristic peaks confirm the presence of functional groups associated with PE-CEO and polymer interactions. The broad absorption band around 3300 cm−1 corresponds to O–H stretching vibrations, indicating hydrogen bonding between the biopolymer and PE-CEO components [24]. The intensity of the peaks at 1730 cm

• −1 (C=O stretching from ester or carboxyl groups) and 1600 cm−1 (C=C stretching of aromatic rings) changes with increasing PE-CEO concentration, suggesting interactions between PE-CEO and the polymer network [44]. These variations indicate successful incorporation of PE-CEO, which could influence the

• in diameter and ≈1 μm in length. Pure BP films (Figure 3b) exhibited a relatively smooth surface with visible small pores, indicative of weak intermolecular interactions. The incorporation of NC into the PVA matrix significantly reduced surface roughness and void formation, suggesting enhanced

Hydrogels and nanogels: effectiveness in dermal applications

• Jéssica da Cruz Ludwig,
• Diana Fortkamp Grigoletto,
• Daniele Fernanda Renzi,
• Wolf-Rainer Abraham,
• Daniel de Paula and
• Najeh Maissar Khalil

Beilstein J. Nanotechnol. 2025, 16, 1216–1233, doi:10.3762/bjnano.16.90

• - or intermolecularly cross-linked by chemical bonding or physical interaction (Figure 1). Physical cross-linking is performed using interactions other than the covalent bond, such as hydrogen bonding or ionic interaction. Physical cross-links can be reversibly dissociated and recombined under specific

• (intramolecular) [44][57][148]. The process of nanogel particle formation may involve physical methods [164] or chemical reactions [165]. For example, nanogels can be obtained through electrostatic interactions generated by the ionization technique with electrospray [166]. Ionizing radiation can also be used for

• thermodynamic activity of the system). Thus, the physicochemical properties related to the first approach involve only the interactions between drugs and vehicles. On the other hand, changing the drug solubility and/or its diffusion through SC is much more complex and comprises multiple interactions among drug

Chitosan nanocomposite containing rotenoids: an alternative bioinsecticidal approach for the management of Aedes aegypti

• Maria A. A. Bertonceli,
• Vitor D. C. Cristo,
• Ivo J. Vieira,
• Francisco J. A. Lemos,
• Arnoldo R. Façanha,
• Raimundo Braz-Filho,
• Gustavo V. T. Batista,
• Luis G. M. Basso,
• Sérgio H. Seabra,
• Thalya S. R. Nogueira,
• Felipe F. Moreira,
• Arícia L. E. M. Assis,
• Antônia E. A. Oliveira and
• Kátia V. S. Fernandes

Beilstein J. Nanotechnol. 2025, 16, 1197–1208, doi:10.3762/bjnano.16.88

• potential values > ±30 mV are indicative of nanoparticle stability, as strong electrostatic repulsion prevents aggregation and ensures colloidal stability [20][21]. While these measurements provide important physicochemical insights, further evidence of the chemical incorporation and potential interactions

• nanocomposite. Additionally, a noticeable reduction in the intensity of the amide-related bands in CS/TPP-β-CD-rot suggests possible interactions – such as hydrogen bonding or covalent bonding – between rotenoids and the chitosan matrix. These spectral features confirm the successful incorporation of rotenoids

• into the chitosan-based nanocomposite and suggest molecular interactions that may contribute to the enhanced stability and bioactivity of the formulation. To complement the physicochemical characterization and confirm the efficiency of rotenoid encapsulation within the nanoparticles, a calibration

Electronic and optical properties of chloropicrin adsorbed ZnS nanotubes: first principle analysis

• Prakash Yadav,
• Boddepalli SanthiBhushan and
• Anurag Srivastava

Beilstein J. Nanotechnol. 2025, 16, 1184–1196, doi:10.3762/bjnano.16.87

• slight strain in the lattice. A vacuum slab of 20 Å thickness was introduced along the radial direction to minimize spurious interactions between adjacent NT images in the simulation. This ensures that the periodic boundary conditions do not artificially influence the electronic and structural properties

• could form a surface dipole, enhancing the interaction of the NT with external molecules. Such structural features are particularly relevant for potential applications in gas sensing, where surface interactions play a critical role in sensitivity and selectivity. The adsorption energy Eads for CP with

• comparison to the oxygen atoms of CP, which may be attributed to the availability of three lone pairs with each chlorine atom in comparison to the two lone pairs with each oxygen atoms. To gain deeper insight into these interactions, a Mulliken population analysis was performed, revealing the extent of

Mechanical stability of individual bacterial cells under different osmotic pressure conditions: a nanoindentation study of Pseudomonas aeruginosa

• Lizeth García-Torres,
• Idania De Alba Montero,
• Eleazar Samuel Kolosovas-Machuca,
• Facundo Ruiz,
• Sumati Bhatia,
• Jose Luis Cuellar Camacho and
• Jaime Ruiz-García

Beilstein J. Nanotechnol. 2025, 16, 1171–1183, doi:10.3762/bjnano.16.86

• bacterial adhesion through short-range electrostatic and hydrophobic interactions. Before deposition on the PLL-coated substrate, the bacterial suspension was centrifuged at 2500 rpm for 3 min, and the resulting supernatant was removed. The bacteria were then resuspended in 150 μL of PBS to increase their

• loading force of 500 pN for each nanoindentation applied in a pre-programmed grid of 48 points per line to quantify surface interactions and the mechanical response of bacteria. This allowed us to simultaneously acquire maps with enough resolution on the sample surface to identify individual bacteria and

• obtain the mechanical response from the membrane rigidity within a reversible regime. The advantage of mapping bacteria at low loading forces is that surface interactions between the tip and cell membrane can be analyzed, and information related to its adhesion or surface charge could be revealed with

Crystalline and amorphous structure selectivity of ignoble high-entropy alloy nanoparticles during laser ablation in organic liquids is set by pulse duration

• Robert Stuckert,
• Felix Pohl,
• Oleg Prymak,
• Ulrich Schürmann,
• Christoph Rehbock,
• Lorenz Kienle and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2025, 16, 1141–1159, doi:10.3762/bjnano.16.84

• ), while the carbon species inside the particle core also resemble metal-carbon species [103][104], although a clear classification and quantification is difficult due to the presence of multiple elements. Thus, multiple interactions may lead to signal shifts that can easily be misinterpreted. Still, the

Deep learning for enhancement of low-resolution and noisy scanning probe microscopy images

• Samuel Gelman,
• Irit Rosenhek-Goldian,
• Nir Kampf,
• Marek Patočka,
• Maricarmen Rios,
• Marcos Penedo,
• Georg Fantner,
• Amir Beker,
• Sidney R. Cohen and
• Ido Azuri

Beilstein J. Nanotechnol. 2025, 16, 1129–1140, doi:10.3762/bjnano.16.83

• interactions. Scanning distortions due to non-linearities in the scan are also trickier to correct and harder to avoid in fast scanning. Some of these artifacts can be eliminated or attenuated by image processing techniques [4][5][6][7][8][9][10][11][12]. Another resolution-limiting factor in AFM is the tip

Fabrication of metal complex phthalocyanine and porphyrin nanoparticle aqueous colloids by pulsed laser fragmentation in liquid and their potential application to a photosensitizer for photodynamic therapy

• Taisei Himeda,
• Risako Kunitomi,
• Ryosuke Nabeya,
• Tamotsu Zako and
• Tsuyoshi Asahi

Beilstein J. Nanotechnol. 2025, 16, 1088–1096, doi:10.3762/bjnano.16.80

• solution remained stably dispersed in PBS, as was the case for AlClPc (Figure S4, Supporting Information File 1). The results indicate that the nanoparticles generated by pulsed laser irradiation will be coated tightly with F-127 molecules through hydrophobic interactions between the extremely hydrophobic

• hydrophobic interactions between the hydrophobic nanoparticles’ surface and the hydrophobic PPO block of F-127. A nanoemulsion having a core (MPcs or PtOEP nanoparticle)–shell (F-127) structure formed immediately after laser fragmentation of microcrystals, leading to the generation of highly dispersive

Piezoelectricity of hexagonal boron nitrides improves bone tissue generation as tested on osteoblasts

• Sevin Adiguzel,
• Nilay Cicek,
• Zehra Cobandede,
• Feray B. Misirlioglu,
• Hulya Yilmaz and
• Mustafa Culha

Beilstein J. Nanotechnol. 2025, 16, 1068–1081, doi:10.3762/bjnano.16.78

• [30][31]. The piezoelectric property of 2D hBN arises from its noncentrosymmetric structure, supported by these van der Waals interactions [32]. The excellent biocompatibility of hBN makes it attractive for diverse applications, including cosmetics, drug delivery, cancer treatment, orthopedic implants

• performed to investigate the main interactions between HOb cells and NMs with US stimulation. HOb cells were cultured in a High-Glucose Dulbecco’s Modified Eagle Medium/Nutrient Mixture F-12 (DMEM/F-12) (Pan Biotech) medium containing 10% fetal bovine serum (FBS) (Pan Biotech), 1% penicillin streptomycin

Soft materials nanoarchitectonics: liquid crystals, polymers, gels, biomaterials, and others

• Katsuhiko Ariga

Beilstein J. Nanotechnol. 2025, 16, 1025–1067, doi:10.3762/bjnano.16.77

• heterocoronene discotic liquid phase molecules can also serve as an excellent case study for intermolecular interactions in bulky molecular systems. Based on molecular nanoarchitectonics, this will facilitate the establishment of design rules for optimal performance in device applications. Extended π-conjugated

• polyelectrolyte–surfactant complexes (Figure 10) [260]. The complex structures consist of polyaniline appended with amino groups and monododecyl phosphate. The intricate films were produced using a spin coating method. The films displayed distinct lamellar structures, resulting from the strong interactions

A calix[4]arene-based supramolecular nanoassembly targeting cancer cells and triggering the release of nitric oxide with green light

• Cristina Parisi,
• Loredana Ferreri,
• Tassia J. Martins,
• Francesca Laneri,
• Samantha Sollima,
• Antonina Azzolina,
• Antonella Cusimano,
• Nicola D’Antona,
• Grazia M. L. Consoli and
• Salvatore Sortino

Beilstein J. Nanotechnol. 2025, 16, 1003–1013, doi:10.3762/bjnano.16.75

• with a PI of ca. 0.3 (inset Figure 4A). The supramolecular construct 1·2 was stable for days, and its formation and stability can be reasonably attributed to both hydrophobic and stacking interactions between the aliphatic chains and the aromatic regions of the host and guest components. Encapsulation