Key for crossing the BBB with nanoparticles: the rational design

• Sonia M. Lombardo,
• Marc Schneider,
• Akif E. Türeli and
• Nazende Günday Türeli

Beilstein J. Nanotechnol. 2020, 11, 866–883, doi:10.3762/bjnano.11.72

• ., the polymer and API in use. Surface functionalization To be able to cross the BBB by RMT, nanoparticle surfaces can be functionalized with specific ligands. This approach has been well studied and a multitude of different ligands has been tested. Some of the recent advances for this approach are

• LRP1, also enables BBB crossing. Another extensively studied RMT pathway is through transferrin and lactoferrin receptors by conjugating nanoparticles with their respective ligands, transferrin and lactoferrin [72][73][74][87][88]. However, these nanoparticles have to face competition with the

• endogenous ligands of these receptors. This problem can be avoided by using antibodies against transferrin receptors, i.e., OX26, which bind to another binding site of the receptor [74][80][81][82][83]. However, it has been shown that OX26 is mostly associated with brain capillaries through the brain

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

• without forming stable adhesions. After infringement of the vasculature proteins like VWF, collagen and fibronectin are exposed on the sub-endothelial matrix and act as ligands for the platelet surface receptors, such as glycoproteins like GPVI and GPIbα, that lead the platelet adhesion to the affected

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

Beilstein J. Nanotechnol. 2020, 11, 533–546, doi:10.3762/bjnano.11.42

• an exact number of metal atoms and surface ligands (Figure 1A,B). Therefore, NCs are considered as colloidal molecules. Similar to plasmonic nanoparticles, the stability of NCs can be controlled by ligand passivation using small molecules, synthetic polymers or biomacromolecules. A significant

• single atom. Additionally, due to covalently bound ligands, the NCs show extraordinary stability under ambient conditions. While plasmonic AuNPs display size-dependent surface plasmon resonance (SPR), NCs display characteristic molecule-like electronic spectra. This is attributed to the small size and

• . Review Luminescent gold nanoclusters Luminescent AuNCs show high photostability and biocompatibility and are nontoxic [41]. Their size is highly precise and small compared to QDs, offering a better internalization in cells and tissues [42][43][44][45][46][47]. The presence of surface ligands allows for a

Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

• Varsha Sharma and
• Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

• of copper in CuAAC may be undesirable in certain biological applications as it is toxic to cells. This copper content can also cause aggregation of proteins and degradation of some biomolecules, which can be avoided by using chelating agents [101]. Incorporation of biomolecules Biomolecular ligands

• such as proteins (e.g., antibodies, peptides, receptor molecules, etc.), lipids and carbohydrates have long been used for targeted delivery. The attachment of these ligands to the external multilayers can be achieved by covalent as well as noncovalent interactions. For example, the HuA33 antibody

• application in implants or tissue engineering. Another strategy for biomolecular functionalization is covalently linking the receptor specific ligands to one of the layer components that are known to interact with cancer cell receptors. For instance, the improved cell adhesion and proliferation was observed

Preparation and in vivo evaluation of glyco-gold nanoparticles carrying synthetic mycobacterial hexaarabinofuranoside

• Gennady L. Burygin,
• Polina I. Abronina,
• Nikita M. Podvalnyy,
• Sergey A. Staroverov,
• Leonid O. Kononov and
• Lev A. Dykman

Beilstein J. Nanotechnol. 2020, 11, 480–493, doi:10.3762/bjnano.11.39

• pre-formed citrate-stabilized GNPs [67] or during the in situ synthesis of glyco-GNPs [32][38][46]. It is also possible to conjugate suitably derivatized glycans [48] via additional functional groups of thiol-functionalized ligands attached to the surface of pre-formed GNPs. We, however, chose an

• alternative approach that relies on the direct conjugation of amino-functionalized Ara6 glycosides with pre-formed citrate-stabilized GNPs that possess no additional ligands. The use of amine-terminated ligands for binding with GNPs is well established [68][69][70][71] although not very popular with glycans

• ], which enables the exchange of citrate ligands with amines. The amine-capped GNPs are stable enough to be used as targeting agents for drug-delivery applications [75], as antigens for the generation of antibodies [77], or as antimicrobial agents [78]. These nanoconjugates are nontoxic, effectively

Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• of studies on semiconductor particles ligands or capping agents are used that bind to the surface of the particles covering them with an electrically insulating shell. Since the transport of charge carriers and/or energy across interfaces is desirable for a variety of applications, the use of π

• -conjugated ligands becomes increasingly interesting. Among them are compounds that react to external stimuli. Molecular switches in particular are fascinating because the properties of the interfaces can be potentially adjusted as required. However, there is debate about how the properties of such special

• ligands are influenced by the presence of a semiconductor and vice versa. Here ammonium-modified azobenzene compounds were selected as prototypes for molecular switches and organic–inorganic hybrid perovskites as semiconductor materials. The class of ammonium–lead–halide phases as prototypes is peculiar

Nanoparticles based on the zwitterionic pillar[5]arene and Ag⁺: synthesis, self-assembly and cytotoxicity in the human lung cancer cell line A549

• Dmitriy N. Shurpik,
• Denis A. Sevastyanov,
• Pavel V. Zelenikhin,
• Pavel L. Padnya,
• Vladimir G. Evtugyn,
• Yuriy N. Osin and
• Ivan I. Stoikov

Beilstein J. Nanotechnol. 2020, 11, 421–431, doi:10.3762/bjnano.11.33

• toxicity of Ag+ ions, multicore complexes prepared on the basis of macrocyclic ligands [9][10][11][12][13] and silver ions are of greatest interest. The ability of macrocyclic systems to form supramolecular associates, due to noncovalent interactions with Ag+, can reduce toxicity and preserve the

Brome mosaic virus-like particles as siRNA nanocarriers for biomedical purposes

• Alfredo Nuñez-Rivera,
• Pierrick G. J. Fournier,
• Danna L. Arellano,
• Ana G. Rodriguez-Hernandez,
• Rafael Vazquez-Duhalt and
• Ruben D. Cadena-Nava

Beilstein J. Nanotechnol. 2020, 11, 372–382, doi:10.3762/bjnano.11.28

• . Nanoparticles offer several advantages such as their size and a surface area that could be functionalized with specific ligands in order to be targeted to specific tissues [10]. Additionally, they can be used to increase the overall solubility of drugs and to modulate their circulation half-life [11][12][13

• potential candidate to deliver siRNA. The versatility of these plant virus nanocarriers includes the functionalization of the viral capsid surface with specific ligands, e.g., folic acid, antibodies, or modified mannose, which further increase the recognition of specific targeted tissues or tumor cells. The

Interactions at the cell membrane and pathways of internalization of nano-sized materials for nanomedicine

• Valentina Francia,
• Daphne Montizaan and
• Anna Salvati

Beilstein J. Nanotechnol. 2020, 11, 338–353, doi:10.3762/bjnano.11.25

• physiological ligands? Or do the receptors mediate just the initial adhesion and is it the nano-sized material itself that triggers its own internalization, perhaps by other ways (as also illustrated in Figure 2D)? How are uptake efficiency and the mechanisms of internalization modulated by the type of receptor

Using gold nanoparticles to detect single-nucleotide polymorphisms: toward liquid biopsy

• María Sanromán Iglesias and
• Marek Grzelczak

Beilstein J. Nanotechnol. 2020, 11, 263–284, doi:10.3762/bjnano.11.20

• and selectivity of an assay. The inhibition of binding events by the corona layer may lead to false negatives, while corona-mediated unspecific binding leads to false positives. To minimize the protein adsorption, one can tailor the chemical composition of ligands by the use of zwitterionic compounds

Rational design of block copolymer self-assemblies in photodynamic therapy

• Maxime Demazeau,
• Laure Gibot,
• Anne-Françoise Mingotaud,
• Patricia Vicendo,
• Clément Roux and
• Barbara Lonetti

Beilstein J. Nanotechnol. 2020, 11, 180–212, doi:10.3762/bjnano.11.15

• modification of the PS by introducing bulky aromatic ligands which inhibited the formation of H-aggregates [37] (Figure 11). A special case is that of PICs, which are based on electrostatic interactions between a charged PS and an oppositely charged copolymer. This approach was first described for PDT by

Molecular architectonics of DNA for functional nanoarchitectures

• Debasis Ghosh,
• Lakshmi P. Datta and
• Thimmaiah Govindaraju

Beilstein J. Nanotechnol. 2020, 11, 124–140, doi:10.3762/bjnano.11.11

• co-workers showed that self-assembled DNA tetrahedron nanoarchitectures with narrow size distribution could deliver siRNA into tumor cells [71]. The programmable DNA strands were functionalized with tumor-targeting folate ligands. The nanoarchitecture consisted of six DNA strands having a total of

Internalization mechanisms of cell-penetrating peptides

• Ivana Ruseska and
• Andreas Zimmer

Beilstein J. Nanotechnol. 2020, 11, 101–123, doi:10.3762/bjnano.11.10

• in the initiation of macropinocytosis. After the interaction with extracellular ligands, multimerization of syndecans is thought to occur, which in turn induces actin polymerization. Arginine-rich peptides have shown to have this effect on the cellular signal transduction via syndecan multimerization

• NRP1, a transmembrane protein and a co-receptor of various ligands, and it has several structural requirements for the peptide: it should have C-terminal arginine with a free α-carboxyl group and the natural ʟ-conformation. It is thought that the binding of TAT to NRP1 could induce macropinocytosis

• cellular membranes [75]. Scavenger receptors are known to bind promiscuously to polyanionic ligands and were shown to be involved in multiple endocytic pathways (macropinocytosis, CME, and caveolae-dependent endocytosis). In several papers, it has been demonstrated that the scavenger receptors class A3 and

Gold and silver dichroic nanocomposite in the quest for 3D printing the Lycurgus cup

• Lars Kool,
• Floris Dekker,
• Anton Bunschoten,
• Glen J. Smales,
• Brian R. Pauw,
• Aldrik H. Velders and
• Vittorio Saggiomo

Beilstein J. Nanotechnol. 2020, 11, 16–23, doi:10.3762/bjnano.11.2

• in a brown coloured solution. We speculate that, as both nanoparticles are not coated with strong ligands, they are prone to metallic exchange between them. To avoid this, we embedded gold and silver nanoparticles separately in PVA for manufacturing AuNP@PVA and Ag@PVA nanocomposites (Supporting

The different ways to chitosan/hyaluronic acid nanoparticles: templated vs direct complexation. Influence of particle preparation on morphology, cell uptake and silencing efficiency

• Arianna Gennari,
• Julio M. Rios de la Rosa,
• Erwin Hohn,
• Maria Pelliccia,
• Enrique Lallana,
• Roberto Donno,
• Annalisa Tirella and
• Nicola Tirelli

Beilstein J. Nanotechnol. 2019, 10, 2594–2608, doi:10.3762/bjnano.10.250

• better exposure of HA-bound ligands [16]. The more general conclusion, however, is the strongly cell-dependent nature of the effects that nanoparticle morphology may have on nanoparticle internalization and silencing performance (see point A in the previous paragraph). This highlights the need of a

Advanced hybrid nanomaterials

• Andreas Taubert,
• Fabrice Leroux,
• Pierre Rabu and
• Verónica de Zea Bermudez

Beilstein J. Nanotechnol. 2019, 10, 2563–2567, doi:10.3762/bjnano.10.247

• -ionothermal reaction or organic ligands are reported in “Magnetic and luminescent coordination networks based on imidazolium salts and lanthanides for sensitive ratiometric thermometry” [35]. Compounds associating the imidazolium ligand with several rare earth ions behave as a ratiometric thermometer and

Bombesin receptor-targeted liposomes for enhanced delivery to lung cancer cells

• Mohammad J. Akbar,
• Pâmela C. Lukasewicz Ferreira,
• Melania Giorgetti,
• Leanne Stokes and
• Christopher J. Morris

Beilstein J. Nanotechnol. 2019, 10, 2553–2562, doi:10.3762/bjnano.10.246

• , leading to accumulation of nanocarriers in the tumour. A diversity of targeting ligands has been explored, including antibodies, proteins, peptides and aptamers. Targeted nanoparticles such as HER2-targeted MM-302 [14], transferrin receptor-targeted CALAA-01 [15], and prostate-specific membrane antigen

• ]. SCLC growth as a result of stimulation by nanoparticle targeting ligands is highly undesirable. We therefore sought to explore the use of GRPR antagonist peptides on the liposomal carriers. Here, we exploited a peptide derived from the work of Mansi et al. who showed that the radiolabelled antagonist

Self-assembly of a terbium(III) 1D coordination polymer on mica

• Quentin Evrard,
• Giuseppe Cucinotta,
• Felix Houard,
• Guillaume Calvez,
• Yan Suffren,
• Carole Daiguebonne,
• Olivier Guillou,
• Andrea Caneschi,
• Matteo Mannini and
• Kevin Bernot

Beilstein J. Nanotechnol. 2019, 10, 2440–2448, doi:10.3762/bjnano.10.234

• the 4f orbitals [15]. This emission can be considerably enhanced when the ions are properly coordinated by organic ligands that act as “antennas” for UV irradiation increasing the overall brightness of the compound [14]. In our present work, we have used [Tb(hfac)3·2H2O]n (where hfac

• mica, however, exhibits a wide excitation band around 312 nm, which could arise from an important change of the local environment of [Tb(hfac)3·2H2O] with the presence of water and potassium ions in close proximity to the hfac ligands. Discussion As previously described [22], the crystal structure of

• [Tb(hfac)3·2H2O] contains one single crystallographically independent TbIII ion. The ion is eightfold coordinated by six oxygen atoms coming from three chelating hfac ligands and by two additional water molecules. Overall, this coordination pattern leads to a slightly distorted square antiprism

Coating of upconversion nanoparticles with silica nanoshells of 5–250 nm thickness

• Cynthia Kembuan,
• Maysoon Saleh,
• Bastian Rühle,
• Ute Resch-Genger and
• Christina Graf

Beilstein J. Nanotechnol. 2019, 10, 2410–2421, doi:10.3762/bjnano.10.231

• iron oxide NP, the oleate ligands on the NP surface are at least partly exchanged for the surfactant as well as the hydrolyzed TEOS upon addition of the oleate-functionalized NPs to the Igepal CO-520–cyclohexane system [36][47]. A similar process is assumed for the oleate-capped UCNPs. As the size of

• Information File 1). This supports that all TEOS grows as SiO2 on the existing core particles. The observation that the measured shell thickness was slightly larger than the calculated one can be explained by the fact that the total mass of the particles, including the oleate ligands, was used for the

• calculations. The oleate ligands are, however, exchanged during shell growth in the inverse microemulsion [36][47]. The oleate content for particles of this size was in the range of 5–10 wt % as shown by thermogravimetric analysis [57]. The z-average values of the samples after the first and second shell

Mannosylated brush copolymers based on poly(ethylene glycol) and poly(ε-caprolactone) as multivalent lectin-binding nanomaterials

• Stefania Ordanini,
• Wanda Celentano,
• Anna Bernardi and
• Francesco Cellesi

Beilstein J. Nanotechnol. 2019, 10, 2192–2206, doi:10.3762/bjnano.10.212

• saccharide–protein connections. Carbohydrate-binding proteins are known as lectins. A way to interfere with pathological carbohydrate–protein interactions is the use of artificial ligands able to antagonize lectins, possibly with higher affinity than the natural ligands. Multivalent glycoconjugates have been

• corresponding partially galactose-functionalized molecules [13]. Analogous copolymers were tested as ligands for DC-SIGN, a tetravalent lectin involved in the early stage of HIV infection [1]. Also in this case, molecules presenting the highest mannose density had the highest activity towards the lectin [14]. A

• ]. In this work, we used ATRP to produce a library of brush copolymers, which were synthesized via random copolymerisation of PEG- and PCL-based macromonomers. Their polymeric backbones were then mannosylated through a post-polymerization CuAAC, in order to obtain potential lectin ligands. Copolymers of

Review of advanced sensor devices employing nanoarchitectonics concepts

• Katsuhiko Ariga,
• Tatsuyuki Makita,
• Masato Ito,
• Taizo Mori,
• Shun Watanabe and
• Jun Takeya

Beilstein J. Nanotechnol. 2019, 10, 2014–2030, doi:10.3762/bjnano.10.198

• structure and switchable luminescence capability for sensitive water detection [131]. The metal–organic framework sensor was prepared from Zn and (5-(2-(5-fluoro-2-hydroxyphenyl)-4,5-bis(4-fluorophenyl)-1H-imidazol-1-yl)isophthalic acid) ligands, the latter of which shows a characteristic excited state

Pulsed laser synthesis of highly active Ag–Rh and Ag–Pt antenna–reactor-type plasmonic catalysts

• Kenneth A. Kane and
• Massimo F. Bertino

Beilstein J. Nanotechnol. 2019, 10, 1958–1963, doi:10.3762/bjnano.10.192

• benefits: (1) the absence of surfactants and ligands; (2) a simple, robust, and quick two-step method production; (3) bulk targets of the constituent metals as the only necessary ingredients. Experimental The synthesis of the monometallic colloids was carried out using a EKSPLA SL312G/SH/TH pulsed laser

Charge-transfer interactions between fullerenes and a mesoporous tetrathiafulvalene-based metal–organic framework

• Manuel Souto,
• Joaquín Calbo,
• Samuel Mañas-Valero,
• Aron Walsh and
• Guillermo Mínguez Espallargas

Beilstein J. Nanotechnol. 2019, 10, 1883–1893, doi:10.3762/bjnano.10.183

• C60 and discrete π-extended TTF molecules have been extensively studied in solution during the last years [42][43][44][45][46][47]. In contrast, much less is known about their supramolecular interactions in solid-state polymeric structures such as metal–organic frameworks. MOFs using TTF as ligands

• is based on the 6-connected trimeric cluster [Fe3(μ3O)(COO)6] as secondary building unit (SBU) and tetratopic tetrathiafulvalene-tetrabenzoate (TTFTB4−) ligands. This MOF shows a hierarchical structure with mesoporous channels of ≈3 nm and orthogonal microporous channels of ≈1 nm. In addition, it

• exhibits an enhanced catalytic activity for the aerobic oxidation of dibenzothiophene in diesel [52], and a reversible continuous breathing upon adsorption of different solvents [53]. Importantly, the planarity of the TTF ligands can be modulated by the breathing behaviour, which directly impacts on its

Long-term entrapment and temperature-controlled-release of SF₆ gas in metal–organic frameworks (MOFs)

• Hana Bunzen,
• Andreas Kalytta-Mewes,
• Leo van Wüllen and
• Dirk Volkmer

Beilstein J. Nanotechnol. 2019, 10, 1851–1859, doi:10.3762/bjnano.10.180

• benzotriazolate ligands, was used to entrap SF6 gas molecules inside its pores, and thus a new scheme for long-term leakproof storage of dangerous gasses is demonstrated. The SF6 gas was introduced into the pores at an elevated gas pressure and temperature. Upon cooling down and release of the gas pressure, we

• frameworks (MOFs); sulfur hexafluoride; Introduction Metal–organic frameworks (MOFs) are coordination polymers with organic ligands containing (potential) voids [1]. Their porosity and high surface area make them attractive materials for adsorption-based applications [2][3][4][5]. MOFs have been suggested

• light of the close-packed arrangement of coordinated chloride ligands in the framework structure. According to the potential energy curve, an activation energy of approximately +218 kJ·mol−1 can be estimated, which is significantly higher than the experimental value of +135 kJ·mol−1, as gleaned from the

Toxicity and safety study of silver and gold nanoparticles functionalized with cysteine and glutathione

• Barbara Pem,
• Igor M. Pongrac,
• Lea Ulm,
• Ivan Pavičić,
• Valerije Vrček,
• Darija Domazet Jurašin,
• Marija Ljubojević,
• Adela Krivohlavek and
• Ivana Vinković Vrček

Beilstein J. Nanotechnol. 2019, 10, 1802–1817, doi:10.3762/bjnano.10.175

• signals from ligands bound to NPs display broad line widths [62][63][64]. Exactly the same 1H NMR profile was recorded for the reaction mixture which consisted of cysteine and NaBH4, i.e., no metallic salt was added (see Figure S4 in Supporting Information File 1). This means that during the regular