Self-assembly of amino acids toward functional biomaterials

• Huan Ren,
• Lifang Wu,
• Lina Tan,
• Yanni Bao,
• Yuchen Ma,
• Yong Jin and
• Qianli Zou

Beilstein J. Nanotechnol. 2021, 12, 1140–1150, doi:10.3762/bjnano.12.85

• ) melanin through a Schiff base reaction to form an adhesive layer, and Fmoc-ʟ-Lys/DOPA fiber simulated an antenna to capture light. As a photosensitizer, Sn(IV)tetrakis(4-pyridyl)porphyrin (SnTPyP) was combined with the photocatalyst Co3O4 NPs by coordination bonds and electrostatic interaction onto the

• linked by ester bonds, which help to maintain the camptothecin ring stability. The assembly can effectively enhance blood circulation, tumor accumulation and cellular uptake. In addition, arginine-modified camptothecin can be combined with anionic cisplatin–polyglutamic acid through electrostatic

• interaction to construct a co-delivery system. Conclusion The self-assembly of biomolecules is based on the noncovalent interaction and the bottom-up combination of ordered 3D structures. Nanotechnology is the driving force of self-assembly, and it has made great contributions to the field of biology and

pH-driven enhancement of anti-tubercular drug loading on iron oxide nanoparticles for drug delivery in macrophages

• Karishma Berta Cotta,
• Sarika Mehra and
• Rajdip Bandyopadhyaya

Beilstein J. Nanotechnol. 2021, 12, 1127–1139, doi:10.3762/bjnano.12.84

• acid with fluorine and a piperazine ring [25]. It exhibits a zwitterionic nature, with a pKa1 and pKa2 of 6.2 and 8.5, respectively [26]. Zwitterionic molecules like amino acids and amphoteric hydroxy groups get adsorbed onto iron oxide nanoparticles predominately via electrostatic interaction [27][28

• drug loading is 3 times greater than determined for NOR@IONPs synthesized in our previous study, where the drug coating was estimated to be 17.13 µg/mg of the nanoparticle [30]. At pH 5, we know from the zeta potential that, IONPs express a positive charge (Figure 2d). Therefore, an electrostatic

• interaction would occur between IONP and the negatively charged carboxylate group of NOR, as carboxylate would be present on the zwitterionic NOR± molecule at this acidic pH. The percentage of zwitterionic NOR± form, estimated through the Henderson–Hasselbalch equation is only 5.9% (Supporting Information

Open-loop amplitude-modulation Kelvin probe force microscopy operated in single-pass PeakForce tapping mode

• Gheorghe Stan and
• Pradeep Namboodiri

Beilstein J. Nanotechnol. 2021, 12, 1115–1126, doi:10.3762/bjnano.12.83

• (OL) variant of Kelvin probe force microscopy (KPFM) provides access to the voltage response of the electrostatic interaction between a conductive atomic force microscopy (AFM) probe and the investigated sample. The measured response can be analyzed a posteriori, modeled, and interpreted to include

• of the cantilever to the determined local contact potential difference between the AFM probe and the imaged sample. The removal of this unwanted contribution greatly improved the accuracy of the AM-KPFM measurements to the level of the FM-KPFM counterpart. Keywords: electrostatic interaction; Kelvin

• pass is distributed over the topography line recorded in the first pass. Also, because the response to the applied bias modulation was fully acquired in the proposed OL KPFM implementation, the CPD was determined by modeling the electrostatic interaction between the AFM probe and the sample. This was

Modification of a SERS-active Ag surface to promote adsorption of charged analytes: effect of Cu²⁺ ions

• Bahdan V. Ranishenka,
• Andrei Yu. Panarin,
• Irina A. Chelnokova,
• Sergei N. Terekhov,
• Peter Mojzes and
• Vadim V. Shmanai

Beilstein J. Nanotechnol. 2021, 12, 902–912, doi:10.3762/bjnano.12.67

• the electrostatic interaction between analyte molecules and silver nanoparticles (Ag NPs) on the intensity of surface-enhanced Raman scattering (SERS). For this, we fabricated nanostructured plasmonic films by immobilization of Ag NPs on glass plates and functionalized them by a set of differently

• inversion of the analyte charge played a key role in this case, instead of a change of charge of the substrate surface. Changing the charge of analytes could be a promising way to get clear SERS spectra of negatively charged molecules on Ag SERS-active supports. Keywords: electrostatic interaction

• nanomaterials that were prepared in the absence of halides [22]. It should be noted that the role of halide ions in the SERS activation of Ag-based substrates is not yet fully clarified. A possible explanation could be their effect on the electrostatic interaction between analyte molecules and the surface of

Local stiffness and work function variations of hexagonal boron nitride on Cu(111)

• Abhishek Grewal,
• Yuqi Wang,
• Matthias Münks,
• Klaus Kern and
• Markus Ternes

Beilstein J. Nanotechnol. 2021, 12, 559–565, doi:10.3762/bjnano.12.46

• from the relatively long-ranged electrostatic interaction, which is therefore a weighted average over the relevant size of the tip (radii of 5–10 nm [46]). It is of the same order as the size of the rim and valley regions and, as a result, leads to an underestimation of ΔΦ. Nevertheless, both

Doxorubicin-loaded gold nanorods: a multifunctional chemo-photothermal nanoplatform for cancer management

• Uzma Azeem Awan,
• Abida Raza,
• Shaukat Ali,
• Rida Fatima Saeed and
• Nosheen Akhtar

Beilstein J. Nanotechnol. 2021, 12, 295–303, doi:10.3762/bjnano.12.24

• their biocompatibility and dispersion at physiological pH values. The positive CTAB layer on the GNR surface facilitates electrostatic adsorption of anionic compounds, such as poly(sodium 4-styrenesulfonate) (PSS), which ultimately facilitates electrostatic interaction with cationic anticancerous drugs

• with GNRs and DOX [20][21][22]. Venkatesan et al. developed a DOX-loaded PSS-coated GNR nanoplatform via electrostatic interaction that selectively delivered DOX to target cells and effectively inhibited tumor growth in MCF-7 cells [18]. The killing effect of the DOX@PSSAuNRs was more pronounced at low

PEG/PEI-functionalized single-walled carbon nanotubes as delivery carriers for doxorubicin: synthesis, characterization, and in vitro evaluation

• Shuoye Yang,
• Zhenwei Wang,
• Yahong Ping,
• Yuying Miao,
• Yongmei Xiao,
• Lingbo Qu,
• Lu Zhang,
• Yuansen Hu and
• Jinshui Wang

Beilstein J. Nanotechnol. 2020, 11, 1728–1741, doi:10.3762/bjnano.11.155

• (Figure 6B). This pH-dependent release of DOX loaded by CNTs-PEG-PEI can be attributed to a protonation effect resulting from the conjugation with positively charged amino groups. The encapsulation or detachment of drug molecules largely depends on their electrostatic interaction with the nanocarriers

Controlling the electronic and physical coupling on dielectric thin films

• Philipp Hurdax,
• Michael Hollerer,
• Larissa Egger,
• Georg Koller,
• Xiaosheng Yang,
• Anja Haags,
• Serguei Soubatch,
• Frank Stefan Tautz,
• Mathias Richter,
• Alexander Gottwald,
• Peter Puschnig,
• Martin Sterrer and
• Michael G. Ramsey

Beilstein J. Nanotechnol. 2020, 11, 1492–1503, doi:10.3762/bjnano.11.132

• ) calculations for the isolated molecule indicate that the torsional angle changes from 35 to only 20° upon the formation of the anion. Presumably, the electrostatic interaction of the charged molecules with the substrate completes the planarization. In summary these results suggest that MgO films prepared under

• critical factor for this phase transition is the density of charged molecules present on the surface. The planarization and electrostatic interaction of the charged molecules with the substrate can be expected to reduce the mobility of the charged molecules. These charged molecules will in turn restrict

• concomitant strong decrease in this temperature range. This higher desorption temperature of the charged molecules relative to the neutral molecules can be expected due the electrostatic interaction of the charged molecule with its image charge. It may therefore seem surprising that the onset of the work

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

• high, leading to similar transcytosis efficiency as RMT [45][46]. AMT occurs through electrostatic interaction between a positively charged molecule, protein or peptide and the negatively charged luminal membrane of the brain endothelial cells. This process depends on energy, time and concentration and

Quantitative determination of the interaction potential between two surfaces using frequency-modulated atomic force microscopy

• Nicholas Chan,
• Carrie Lin,
• Tevis Jacobs,
• Robert W. Carpick and
• Philip Egberts

Beilstein J. Nanotechnol. 2020, 11, 729–739, doi:10.3762/bjnano.11.60

• compensation [61][62]. This factor would result in changes in the electrostatic interaction forces between the tip and sample as a function of the tip–sample separation distance. Further investigation into the significance of this dependency should be performed in the context of the silicon oxide–carbon

Adsorptive removal of bulky dye molecules from water with mesoporous polyaniline-derived carbon

• Hyung Jun An,
• Jong Min Park,
• Nazmul Abedin Khan and
• Sung Hwa Jhung

Beilstein J. Nanotechnol. 2020, 11, 597–605, doi:10.3762/bjnano.11.47

• effective at higher pH if the electrostatic interaction is considered. However, there should be other dominant mechanisms since the q6h values are quite high under a wide range of pH conditions. At first, the very high hydrophobicity of KOH-900, as shown in Figure 2, can be considered. Compared with any

Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique

• Matthias Simolka,
• Hanno Kaess and
• Kaspar Andreas Friedrich

Beilstein J. Nanotechnol. 2020, 11, 583–596, doi:10.3762/bjnano.11.46

• mechanisms are piezoelectricity, flexoelectricity and electrostriction. Further contributions are possible by deformation potential generation, electron–hole formation, coupling of electrons and phonons, electrochemical side reactions in the tip–sample junction, electrostatic interaction, and volume

Luminescent gold nanoclusters for bioimaging applications

• Nonappa

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

• electrostatic interaction was ruled out. Instead, the authors assumed that it might be a specific peptide motif of HSA that interacts with the bacterial cell wall. The trypsin digestion of Au-HSA NCs was studied and various fragments were identified using MALDI–MS. To confirm further whether the peptides can

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

• substrates and colloidal particles and the main driving force for alternate deposition of oppositely charged PEs was electrostatic interaction (Figure 3a). These interactions occur in assemblies that use polycations and polyanions such as polypeptides (e.g., poly-ʟ-arginine (Parg) and PLL), polysaccharides

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

• responsible for hemolysis by aggregating red blood cells (RBCs) via bridging force mediated electrostatic interaction [54]. Thus, the hemolytic effect of CB-Hap NRs at high concentration can be reduced by optimizing their surface charge in the future. Antibacterial activity Generally, bacterial colonies can

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

Internalization mechanisms of cell-penetrating peptides

• Ivana Ruseska and
• Andreas Zimmer

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

• complexes with cargo molecules through electrostatic interaction. Pep-1 has successfully been used to deliver small peptides and proteins into cells, while MPG has shown to efficiently deliver small interfering RNA (siRNA) into cultured cell lines [3][10]. The interplay between hydrophilic and hydrophobic

• molecules into cells and is one of the most studied CPPs thus far [25]. The first step in the internalization process is the formation of electrostatic interaction between the peptide and the cellular membrane, which affects the lipid supramolecular organization. This process may lead to changes in the

• the actin remodeling allowed by the GTPase Rac 1, a regulatory molecule activated by electrostatic interaction between MPG and GAGs in the extracellular matrix. The two aforementioned actions might constitute the ‘onset’ of the internalization mechanism and have a part in the impact of MPG on membrane

Fully amino acid-based hydrogel as potential scaffold for cell culturing and drug delivery

• Dávid Juriga,
• Evelin Sipos,
• Orsolya Hegedűs,
• Gábor Varga,
• Miklós Zrínyi,
• Krisztina S. Nagy and
• Angéla Jedlovszky-Hajdú

Beilstein J. Nanotechnol. 2019, 10, 2579–2593, doi:10.3762/bjnano.10.249

• is that it can partially decrease the anionic character of aspartic acid. In addition, LYS also facilitates the electrostatic interaction between anionic plasma membrane sites and cationic polymer sites. Therefore, it supports cell adhesion and proliferation [47]. The swelling, mechanical and

The role of Ag⁺, Ca²⁺, Pb²⁺ and Al³⁺ adions in the SERS turn-on effect of anionic analytes

• Stefania D. Iancu,
• Andrei Stefancu,
• Vlad Moisoiu,
• Loredana F. Leopold and
• Nicolae Leopold

Beilstein J. Nanotechnol. 2019, 10, 2338–2345, doi:10.3762/bjnano.10.224

• − showing a high affinity for the silver surface. The colloidal nanoparticles used here are surrounded by citrate anions in an electrostatic interaction with the silver surface, which confer the nanoparticles a negative zeta potential and thus electrostatically stabilize the AgNPs and prevent aggregation

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

• [149]. This kind of molecular recognition based on hydrogen bonding and/or electrostatic interaction is weakened in polar media such as water phase. Chemical species with uneven charge distribution within a molecule are stabilized by solvation with polar solvent molecules, which is highly

Multicomponent bionanocomposites based on clay nanoarchitectures for electrochemical devices

• Giulia Lo Dico,
• Bernd Wicklein,
• Lorenzo Lisuzzo,
• Giuseppe Lazzara,
• Pilar Aranda and
• Eduardo Ruiz-Hitzky

Beilstein J. Nanotechnol. 2019, 10, 1303–1315, doi:10.3762/bjnano.10.129

• the inactivity of the entrapped enzyme. This is probably due to the direct interaction of the enzyme with sepiolite and shows the necessity to load the enzyme into the clay nanotubes. It is well known that the electrostatic interaction of proteins with the external surface of sepiolite can be very

Influence of dielectric layer thickness and roughness on topographic effects in magnetic force microscopy

• Alexander Krivcov,
• Jasmin Ehrler,
• Marc Fuhrmann,
• Tanja Junkers and
• Hildegard Möbius

Beilstein J. Nanotechnol. 2019, 10, 1056–1064, doi:10.3762/bjnano.10.106

• ). When a dielectric layer is introduced the capacitive coupling can be reduced so that the overall phase signal becomes negative. Thus, tuning the phase shift due to capacitive coupling by introducing a dielectric layer suppresses the electrostatic interaction and allows the visualization of magnetic

Correlation of surface-enhanced Raman scattering (SERS) with the surface density of gold nanoparticles: evaluation of the critical number of SERS tags for a detectable signal

• Vincenzo Amendola

Beilstein J. Nanotechnol. 2019, 10, 1016–1023, doi:10.3762/bjnano.10.102

• Raman tags in analytical chemistry, biotechnological assays and nanomedicine. (A) Pictorial representation of the Au nanotag (AuNT), consisting of Au nanoparticles (NPs) aggregated by electrostatic interaction with cationic Raman reporters (either MG, MGITC or HITC), all coated with thiolated PEG. (B

Synthesis of MnO₂–CuO–Fe₂O₃/CNTs catalysts: low-temperature SCR activity and formation mechanism

• Yanbing Zhang,
• Lihua Liu,
• Yingzan Chen,
• Xianglong Cheng,
• Chengjian Song,
• Mingjie Ding and
• Haipeng Zhao

Beilstein J. Nanotechnol. 2019, 10, 848–855, doi:10.3762/bjnano.10.85

• formed. The following formation mechanism was inferred: Cu2+ and Fe3+ ions are first adsorbed on the surface of acid-treated CNTs via electrostatic interaction. Then the Cu(NO3)2 and Fe(NO3)3 are partly hydrolyzed in situ into Cu(OH)2, Fe(OH)3, and HNO3 on the CNTs. Afterwards, MnO2 is formed through the

Capillary force-induced superlattice variation atop a nanometer-wide graphene flake and its moiré origin studied by STM

• Loji K. Thomas and
• Michael Reichling

Beilstein J. Nanotechnol. 2019, 10, 804–810, doi:10.3762/bjnano.10.80

• direction (numbered (1)) and folding axis (numbered (2)) along two arm-chair crystallographic directions that differ by 120°, in agreement with previous studies [5][9][21][34]. Theory There are three significant forces existing at a solid–liquid interface [17]: (a) van der Waals; (b) electrostatic

• interaction due to the applied potential difference between the tip and sample [38][39][40][41][42][43] (or tip and graphene [28]), and (c) capillary forces due to the Laplace pressure generated by the formation of a highly curved fluid meniscus between the tip and the surface [29][44][45]. The capillary