Stabilization of nanosized titanium dioxide by cyclodextrin polymers and its photocatalytic effect on the degradation of wastewater pollutants

• Tamás Zoltán Agócs,
• István Puskás,
• Erzsébet Varga,
• Mónika Molnár and
• Éva Fenyvesi

Beilstein J. Org. Chem. 2016, 12, 2873–2882, doi:10.3762/bjoc.12.286

• agent, carboxymethyl β-cyclodextrin polymer for improving the colloidal stability of nanosized TiO2. Dynamic light scattering measurements proved that the aggregation of TiO2 nanoparticles was hindered by the presence of this polymer additive. Studying its influence on the photocatalytic effect on

• by dynamic light scattering: Determination of the particle size distribution of the nanoTiO2 particles and aggregates was performed by dynamic light scattering method (also known as photon correlation spectroscopy) using a Malvern Zetasizer Nano ZS instrument using a He-Ne laser of 4 mW power and 633

Formose reaction accelerated in aerosol-OT reverse micelles

• Makoto Masaoka,
• Tomohiro Michitaka and
• Akihito Hashidzume

Beilstein J. Org. Chem. 2016, 12, 2663–2667, doi:10.3762/bjoc.12.262

• the cases of AOT and CTAB, the radius of the water pools (Rw) was evaluated by dynamic light scattering, whereas, in the case of TX, Rw was estimated by the fluorescence quenching technique. As can be seen in Supporting Information File 1, Figure S1, Rw for AOT and CTAB is almost proportional to the

Stimuli-responsive HBPS-g-PDMAEMA and its application as nanocarrier in loading hydrophobic molecules

• Yongsheng Chen,
• Li Wang,
• Haojie Yu,
• Zain-Ul-Abdin,
• Ruoli Sun,
• Guanghui Jing,
• Rongbai Tong and
• Zheng Deng

Beilstein J. Org. Chem. 2016, 12, 939–949, doi:10.3762/bjoc.12.92

• and zeta potential of the polymer in aqueous solution at different temperature were measured on a Zetasizer 3000HSA dynamic light scattering (DLS)/zeta potential analyzer. The fluorescence spectra were recorded on an F-280 (Tianjin Gangdong) fluorescence spectrophotometer. (A) The synthetic routes to

Supramolecular structures based on regioisomers of cinnamyl-α-cyclodextrins – new media for capillary separation techniques

• Gabor Benkovics,
• Ondrej Hodek,
• Martina Havlikova,
• Zuzana Bosakova,
• Pavel Coufal,
• Milo Malanga,
• Eva Fenyvesi,
• Andras Darcsi,
• Szabolcs Beni and
• Jindrich Jindrich

Beilstein J. Org. Chem. 2016, 12, 97–109, doi:10.3762/bjoc.12.11

• the regioisomers. The ability of the monomers to self-assemble was proved by various methods including NMR spectroscopy and dynamic light scattering (DLS). The light scattering experiments showed that the monomer units have distinguishable ability to form supramolecular structures in different

Aggregation behavior of amphiphilic cyclodextrins in a nonpolar solvent: evidence of large-scale structures by atomistic molecular dynamics simulations and solution studies

• Giuseppina Raffaini,
• Fabio Ganazzoli and
• Antonino Mazzaglia

Beilstein J. Org. Chem. 2016, 12, 73–80, doi:10.3762/bjoc.12.8

• have been usually investigated and characterized in water for their potential use as nanocarriers for drug delivery, but they can also aggregate in apolar solvents, as shown in the present paper through atomistic molecular dynamics simulations and dynamic light scattering measurements. The simulations

• particular at longer lengths. In any case, these nanostructures are stable at least from the kinetic viewpoint for relatively long times thanks to the large number of intermolecular interactions of dipolar and dispersive nature. The dynamic light scattering experiments indicate the presence of aggregates

• ), could be utilized in perspective in a future investigation on similar aCD with n > 0. In the following, we discuss our simulation and experimental results in the order, and then the simulation methodology and the dynamic light scattering procedure in the Experimental section. Results and Discussion

Aggregation behaviour of amphiphilic cyclodextrins: the nucleation stage by atomistic molecular dynamics simulations

• Giuseppina Raffaini,
• Antonino Mazzaglia and
• Fabio Ganazzoli

Beilstein J. Org. Chem. 2015, 11, 2459–2473, doi:10.3762/bjoc.11.267

• was independently confirmed by small-angle X-ray and dynamic light scattering experiments, respectively. We further note that aCD with longer alkyl chains (compound 2 of Scheme 1, data not shown) did not show the presence of isolated molecules in equilibrium with small micelles and larger clusters [24

Size-controlled and redox-responsive supramolecular nanoparticles

• Raquel Mejia-Ariza,
• Gavin A. Kronig and
• Jurriaan Huskens

Beilstein J. Org. Chem. 2015, 11, 2388–2399, doi:10.3762/bjoc.11.260

• ). Equipment Dynamic light scattering (DLS) Hydrodynamic diameters and zeta potentials were measured on a Zetasizer NanoZS (Malvern Instrument Ltd, Malvern, United Kingdom) at 20 °C, with a laser wavelength of 633 nm and a scattering angle of 173°. High resolution scanning electron microscopy (HR-SEM) All SEM

Preparation of Pickering emulsions through interfacial adsorption by soft cyclodextrin nanogels

• Shintaro Kawano,
• Toshiyuki Kida,
• Mitsuru Akashi,
• Hirofumi Sato,
• Motohiro Shizuma and
• Daisuke Ono

Beilstein J. Org. Chem. 2015, 11, 2355–2364, doi:10.3762/bjoc.11.257

• -active property. Results: CD nanogels were prepared by crosslinking heptakis(2,6-di-O-methyl)-β-cyclodextrin with phenyl diisocyanate and subsequent immersion of the resulting polymer in water. A dynamic light scattering study shows that primary CD nanogels with 30–50 nm diameter assemble into larger CD

• nanogels were studied using dynamic light scattering (DLS). Figure 3A shows the DLS data of CD nanogel obtained after redispersion of the freeze-dried DM-β-CD/PDI polymer powder in water. The concentration of the CD nanogel was adjusted to 0.01 and 0.1 wt %. At a 0.01 wt % concentration, a unimodal size

• Information File 1. Dynamic light scattering (DLS) The particle size distribution was measured at 25 °C using DLS6000HL (Otsuka Electronic Co.) equipped with a He-Ne laser (wavelength 632.8 nm). The mean particle diameter was calculated from the diffusion coefficients using the Stokes–Einstein equation. The

Cross-metathesis of polynorbornene with polyoctenamer: a kinetic study

• Yulia I. Denisova,
• Maria L. Gringolts,
• Alexander S. Peregudov,
• Liya B. Krentsel,
• Ekaterina A. Litmanovich,
• Arkadiy D. Litmanovich,
• Eugene Sh. Finkelshtein and
• Yaroslav V. Kudryavtsev

Beilstein J. Org. Chem. 2015, 11, 1796–1808, doi:10.3762/bjoc.11.195

• process thus indicating their higher reactivity, as compared with the polyoctenamer-bound ones. Macroscopic homogeneity of the reacting media is proved by dynamic light scattering from solutions containing the polymer mixture and its components. In general, the studied process can be considered as a new

Impact of multivalent charge presentation on peptide–nanoparticle aggregation

• Daniel Schöne,
• Boris Schade,
• Christoph Böttcher and
• Beate Koksch

Beilstein J. Org. Chem. 2015, 11, 792–803, doi:10.3762/bjoc.11.89

• result in any changes in the CD spectra, indicating that there is no concentration-dependent change in the secondary structure of the peptides. At pH 11 the CD spectra of all peptides are virtually identical and indicate the presence of α-helical coiled-coil structures. Dynamic light scattering (DLS) was

• with a higher number of charges occurs more slowly. Helical wheel representation and sequences of the peptides used in this study. CD spectra of 30 µM peptide VW05, R1A3, R2A2, R2A3, R2A4 and R2A5 at (A) pH 9 and (B) pH 11 in 10 mM Tris/HCl buffer. Dynamic light scattering of (C) VW05 and (D) R2A2 both

• ) Dynamic light scattering of 0.05 µM Au/MUA nanoparticles at pH 9. (B) Cryo TEM image of 0.05 µM Au/MUA nanoparticles at pH 9. (C) UV–vis spectra of 0.05 µM Au/MUA nanoparticles at pH 9 and in the presence of 30 µM VW05. (D) Time and concentration dependent shift in the absorption maximum of 0.05 µM Au/MUA

Multivalent dendritic polyglycerolamine with arginine and histidine end groups for efficient siRNA transfection

• Fatemeh Sheikhi Mehrabadi,
• Hanxiang Zeng,
• Mark Johnson,
• Cathleen Schlesener,
• Zhibin Guan and
• Rainer Haag

Beilstein J. Org. Chem. 2015, 11, 763–772, doi:10.3762/bjoc.11.86

• dynamic light scattering (DLS). Figure 2 shows the size distribution of dPG polyplexes (at N/P ratio 10). The average size of all nanoparticles ranges from 60–100 nm. In general, the AAdPG/siRNA polyplexes were smaller than the corresponding dPG-NH2 50%/siRNA polyplexes. Moreover, AAdPG complexes have a

Glycodendrimers: tools to explore multivalent galectin-1 interactions

• Jonathan M. Cousin and
• Mary J. Cloninger

Beilstein J. Org. Chem. 2015, 11, 739–747, doi:10.3762/bjoc.11.84

• mediated interactions. Dynamic light scattering and fluorescence microscopy were used to study the multivalent interaction of galectin-1 with the glycodendrimers in solution, and glycodendrimers were observed to organize galectin-1 into nanoparticles. In the presence of a large excess of galectin-1

• nanoparticles were characterized using dynamic light scattering (DLS) and fluorescence microscopy (FM) when varying ratios of galectin-1 were added to the glycodendrimers. The galectin-1/glycodendrimer nanoparticle aggregates were then used to inhibit the galectin-1 induced aggregation of DU145 human prostate

• -functionalized PAMAM dendrimers 1–4 were determined by fluorescence microscopy (FM) and dynamic light scattering (DLS). For fluorescence microscopy, galectin-1 was labeled with AlexaFluor-555, and aggregation was characterized when a large, medium, or slight excess of galectin-1 was used relative to the

Potential of acylated peptides to target the influenza A virus

• Daniel Lauster,
• Damian Pawolski,
• Julian Storm,
• Kai Ludwig,
• Rudolf Volkmer,
• Henry Memczak,
• Andreas Herrmann and
• Sumati Bhatia

Beilstein J. Org. Chem. 2015, 11, 589–595, doi:10.3762/bjoc.11.65

• indicates the formation of rather large structures different from a simple sphere-like micelle. To verify and characterize the assembly of our peptides into higher-order structures, we studied exemplarily the organization of C18-PeBGF by dynamic light scattering (DLS) and transmission electron microscopy

Formation of nanoparticles by cooperative inclusion between (S)-camptothecin-modified dextrans and β-cyclodextrin polymers

• Thorbjørn Terndrup Nielsen,
• Catherine Amiel,
• Laurent Duroux,
• Kim Lambertsen Larsen,
• Lars Wagner Städe,
• Reinhard Wimmer and
• Véronique Wintgens

Beilstein J. Org. Chem. 2015, 11, 147–154, doi:10.3762/bjoc.11.14

• polymers. As illustrated in Table 3 the D70GP-CPT2 with a DS of 4.6 mol % forms highly monodisperse nanoparticles when associated with D70HPβ-CD in aqueous media, measured by dynamic light scattering (DLS). The optimum ratio between CPT and β-CD units was found to be 1:1 but even more extreme ratios of 1:4

• D70HPβ-CD at different ratios, measured by dynamic light scattering. Supporting Information Supporting Information File 406: 1H NMR and HSQC spectra of N3CPT and D70GP-CPT2 and ITC data from titration of D70GP-CPT with native β-CD. Acknowledgements The authors would like to thank Oda og Hans

• polymer (45 µM). Nanoparticles were prepared by mixing 0.6 mL of the CPT-dextran solutions with 0.6 mL D70HPβ-CD solutions at room temperature under magnetic stirring at 150 rpm. The mean hydrodynamic diameter and the polydispersity index (PDI) of the nanoparticles were determined by dynamic light

Preparation and evaluation of cyclodextrin polypseudorotaxane with PEGylated liposome as a sustained release drug carrier

• Kayoko Hayashida,
• Taishi Higashi,
• Daichi Kono,
• Keiichi Motoyama,
• Koki Wada and
• Hidetoshi Arima

Beilstein J. Org. Chem. 2014, 10, 2756–2764, doi:10.3762/bjoc.10.292

• resulting precipitate was dried under reduced pressure. Particle size, PDI and ζ-potential of CD PPRX with DOX/PEG-LP The particle size, PDI and ζ-potential of the suspension of γ-CD PPRX with DOX/PEG-LP were determined by dynamic light scattering by using a Zetasizer Nano (Malvern Instruments

• , Worcestershire, UK). The dynamic light scattering was analyzed by the general purpose mode. The measurements were carried out at least in triplicates. FTIR The sample preparation was performed by using the KBr method. The FTIR spectrum of γ-CD PPRX with DOX/PEG-LP was recorded on a JIR-6500W FTIR spectrometer

Linear-g-hyperbranched and cyclodextrin-based amphiphilic block copolymer as a multifunctional nanocarrier

• Yamei Zhao,
• Wei Tian,
• Guang Yang and
• Xiaodong Fan

Beilstein J. Org. Chem. 2014, 10, 2696–2703, doi:10.3762/bjoc.10.284

• –hydrophilic interactions between the inner core and the outer shell. The micelles were prepared by directly adding water to a DMF solution of P3 until the required amount of water for micelle formation was reached. Dynamic light scattering (DLS) and transmission electron microscopy (TEM) measurements were

Encapsulation of biocides by cyclodextrins: toward synergistic effects against pathogens

• Véronique Nardello-Rataj and
• Loïc Leclercq

Beilstein J. Org. Chem. 2014, 10, 2603–2622, doi:10.3762/bjoc.10.273

• several papers [82][83]. In 2010, Jaiswal et al. proposed to use of β-CD as a capping agent [84]. The reduction of silver salts using sodium borohydride followed by β-CD capping allows the synthesis of stable spherical silver nanoparticles. The authors proved by dynamic light scattering that the average

Host–guest-driven color change in water: influence of cyclodextrin on the structure of a copper complex of poly((4-hydroxy-3-(pyridin-3-yldiazenyl)phenethyl)methacrylamide-co-dimethylacrylamide)

• Nils Retzmann,
• Gero Maatz and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 2480–2483, doi:10.3762/bjoc.10.259

• -yldiazenyl)phenethyl)methacrylamide-co-dimethylacrylamide) and its reversible optical and complex-forming properties due to copper and cyclodextrin (CD) interactions. Color changing effects are characterized by UV–vis spectroscopy and the supramolecular behavior is investigated by dynamic light scattering

• addition. Assuming an intermolecular aggregating effect due to ionic interactions between the covalently attached azo dyes in 7 and Cu ions in solution, dynamic light scattering (DLS) experiments in a water/methanol solution were carried out (Figure 3). It was found that, by introducing copper ions to 7

Expeditive synthesis of trithiotriazine-cored glycoclusters and inhibition of Pseudomonas aeruginosa biofilm formation

• Meriem Smadhi,
• Sophie de Bentzmann,
• Anne Imberty,
• Marc Gingras,
• Raoudha Abderrahim and
• Peter G. Goekjian

Beilstein J. Org. Chem. 2014, 10, 1981–1990, doi:10.3762/bjoc.10.206

• . Both homo- and heterobifunctional ligands are obtained by a straightforward preparative route, as an innovative approach. Additionally, isothermal titration calorimetry (ITC) and dynamic light scattering (DLS) helped to better understand lectin–ligand interactions between lecA or lecB and these

• convenient access to low valency mono- or heterobifunctional glycoclusters. As expected, they display excellent aqueous solubility due of the combination of a dendritic polyheterocyclic architecture and carbohydrate epitopes. Biophysical studies Dynamic light scattering experiments (DLS) were performed on

• reported low-valent glycoasterisk α-D-Man ligand based on a persulfurated benzene core [30] and currenly reported β-D-Gal compound 1. Dynamic light scattering experiments of bis-D-galactosyl proparyl cluster 16 with lecA. Distribution by mass for lecA + buffer (left) and lecA + 16 (200 μM, right) at 3

Influence of cyclodextrin on the UCST- and LCST-behavior of poly(2-methacrylamido-caprolactam)-co-(N,N-dimethylacrylamide)

• Alexander Burkhart and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1951–1958, doi:10.3762/bjoc.10.203

• amide groups of the copolymer. Besides that, the measured hydrodynamic coil size of about 100 nm via dynamic light scattering (DLS) in different solutions indicates the formation of agglomerates. We also spent some interest in the thermal behavior of copolymers 6 in the condensed state. The observed

Multivalent scaffolds induce galectin-3 aggregation into nanoparticles

• Candace K. Goodman,
• Mark L. Wolfenden,
• Pratima Nangia-Makker,
• Anna K. Michel,
• Avraham Raz and
• Mary J. Cloninger

Beilstein J. Org. Chem. 2014, 10, 1570–1577, doi:10.3762/bjoc.10.162

• . Here, we show that lactose-functionalized dendrimers interact with galectin-3 in a multivalent fashion to form aggregates. The glycodendrimer–galectin aggregates were characterized by dynamic light scattering and fluorescence microscopy methodologies and were found to be discrete particles that

• in the software package. The peaks were analysed using the continuous mode. Mw values for 2–5 are provided in Table S2, Supporting Information File 1. Dynamic light scattering (DLS) DLS measurements were acquired with the Brookhaven 90Plus Particle Size Analyzer equipped with a 15 mW solid state, 633

• and the changes in Mw upon deacetylation, enabling characterization of the average number of sugars per dendrimer [30]. Additional characterization details (including 1H NMR spectra) are provided in Supporting Information File 1. Characterization of dendrimer/galectin-3 aggregates Dynamic light

A promising cellulose-based polyzwitterion with pH-sensitive charges

• Thomas Elschner and
• Thomas Heinze

Beilstein J. Org. Chem. 2014, 10, 1549–1556, doi:10.3762/bjoc.10.159

• ., acid dissociation constants, isoelectric point and complexation, were investigated by potentiometric titration (pH), nephelometry, rheology and dynamic light-scattering. The formation of pH-responsive interpolyelectrolyte complexes applying polydiallyldimethylammonium chloride was preliminary studied

• titration (pH), nephelometry, rheology and dynamic light-scattering. Moreover, preliminary studies about stimuli-responsive interpolyelectrolyte complexes are presented. Results and Discussion Synthesis The synthesis of a novel polyzwitterion based on cellulose was performed by activation of the polymer

• 5 show precipitation below pH values of 5 due to the protonation of the carboxylate and the hydrophobic Boc group. Figure 5 reveals an increase of turbidity with decreasing pH value. Moreover, dynamic light scattering (DLS) display details about the aggregates formed. The measurements of dissolved

Bis(β-lactosyl)-[60]fullerene as novel class of glycolipids useful for the detection and the decontamination of biological toxins of the Ricinus communis family

• Hirofumi Dohi,
• Takeru Kanazawa,
• Akihiro Saito,
• Keita Sato,
• Hirotaka Uzawa,
• Yasuo Seto and
• Yoshihiro Nishida

Beilstein J. Org. Chem. 2014, 10, 1504–1512, doi:10.3762/bjoc.10.155

• aggregates were diluted with dimethyl sulfoxide (DMSO) and dialyzed against distilled water for 2 days to give a colloidal suspension of bis-Lac-C60 with a deep brown color. The derived suspension was stable for at least 6 months when stored at 4 °C in the dark. Dynamic light scattering (DLS) analysis

Biantennary oligoglycines and glyco-oligoglycines self-associating in aqueous medium

• Svetlana V. Tsygankova,
• Alexander A. Chinarev,
• Alexander B. Tuzikov,
• Nikolai Severin,
• Alexey A. Kalachev,
• Juergen P. Rabe,
• Alexandra S. Gambaryan and
• Nicolai V. Bovin

Beilstein J. Org. Chem. 2014, 10, 1372–1382, doi:10.3762/bjoc.10.140

• biantennary oligoglycines to assemble in aqueous media as well as the antiviral activity of glycoderivatives. Study of biantennary oligoglycines association in solution by dynamic light scattering The size of the particles formed by the biantennary oligoglycines in solution was measured with the dynamic light

• (СН2СН2О)3СН2СН2NH-Glyn-Н (n = 2–7), non-associating in aqueous solutions as well as oligoglycines with cores С2 and С10 (n < 4) did not form associates on a mica surface under all studied ranges of pH (from 4.5 to 8.5). According to dynamic light scattering data (see above) only peptide Н-Gly4NH(СН2

• cell. The layer morphology was identical to the one observed in experiments in air (Figure 5). Dynamic light scattering data give evidence that in neutral aqueous solutions the association of compounds Н-Gly5-NH-X-NH-Gly5-Н (cores С2 and С10) leads to the formation of large aggregates. By means of SFM

A new building block for DNA network formation by self-assembly and polymerase chain reaction

• Holger Bußkamp,
• Sascha Keller,
• Marta Robotta,
• Malte Drescher and
• Andreas Marx

Beilstein J. Org. Chem. 2014, 10, 1037–1046, doi:10.3762/bjoc.10.104

• electrophoresis, atomic force microscopy, dynamic light scattering, and electron paramagnetic resonance spectroscopy. The findings indicate that rather rigid DNA networks were formed. This presents a new bottom-up approach for DNA material formation and might find applications like in the generation of functional

• generated by PCR was investigated by dynamic light scattering (DLS). The obtained data indicate that DNA networks are also present in solution. The measured average hydrodynamic diameter (DH) at 90° after 10 measurements were partially 67 nm and 593 nm while the linear DNA showed a DH of 11 nm (see