Enhanced Golden Gate Assembly: evaluating overhang strength for improved ligation efficiency.

Molecular cloning, a routine yet essential technique, relies heavily on efficient ligation, which can be significantly improved using Golden Gate Assembly (GGA). A key component of GGA is the use of type IIS enzymes, which uniquely cleave downstream of their recognition sequences to generate various overhangs, including non-palindromic ones. Recent advancements in GGA include the development of newly engineered enzymes with enhanced activity.

Large-Scale Statistical Analysis of Defect Emission in hBN: Revealing Spectral Families and Influence of Flake Morphology.

Quantum emitters in two-dimensional layered hexagonal boron nitride are quickly emerging as a highly promising platform for next-generation quantum technologies. However, the precise identification and control of defects are key parameters to achieve the next step in their development. We conducted a comprehensive study by analyzing over 10,000 photoluminescence emission lines from liquid exfoliated hBN nanoflake samples, revealing 11 narrow sets of defect families within the 1.

Robust, high-yield, rapid fabrication of DNA constructs for Magnetic Tweezers.

Single-molecule techniques are highly sensitive tools that can reveal reaction intermediates often obscured in experiments involving large ensembles of molecules. Therefore, they provide unprecedented information on the mechanisms that control biomolecular reactions. Currently, one of the most significant single-molecule assays is Magnetic Tweezers (MT), which probes enzymatic reactions at high spatio-temporal resolutions on tens, if not hundreds, of molecules simultaneously.

Aggregation kinetics of a concentrated colloidal suspension under oscillatory flow.

The aggregation behavior of an attractive colloidal silica suspension under oscillatory flow is studied using rheological measurement. We show that the competition between the aggregation of the particles and the aggregate breakup under external stress leads to a non-monotonous evolution of the elastic modulus with time. Remarkably, under certain conditions, the elasticity is not an increasing function of time but exhibits a maximum.

Stress overshoot, hysteresis, and the Bauschinger effect in sheared dense colloidal suspensions.

The mechanical nonlinear response of dense Brownian suspensions of polymer gel particles is studied experimentally and by means of numerical simulations. It is shown that the response to the application of a constant shear rate depends on the previous history of the suspension. When the flow starts from a suspension at rest, it exhibits an elastic response followed by a stress overshoot and then a plastic flow regime.

Magnetic Control over the Fractal Dimension of Supramolecular Rod Networks.

Controlling supramolecular polymerization is of fundamental importance to create advanced materials and devices. Here we show that the thermodynamic equilibrium of Gd-bearing supramolecular rod networks is shifted reversibly at room temperature in a static magnetic field of up to 2 T. Our approach opens opportunities to control the structure formation of other supramolecular or coordination polymers that contain paramagnetic ions.

Jet instability of a shear-thickening concentrated suspension.

We investigate the flow of a concentrated suspension of colloidal particles at deformation rates higher than the discontinuous shear-thickening transition shear rate. We show that, under its own weight, a jet of a concentrated enough colloidal suspension, simultaneously flows while it sustains tensile stress and transmits transverse waves. This results in a new flow instability of jets of shear-thickening suspensions: the jet is submitted to rapid transverse oscillations, that we characterize.

Flexibility and thermal dynamic stability increase of dsDNA induced by Ru(bpy)dppz based on AFM and HRM technique.

Ru(bpy)dppz has been widely used as a probe for exploring the structure of double-stranded DNA (dsDNA). The flexibility change of DNA helix is important in many of its biological functions but not well understood. Here, flexibility change of dsDNA helix caused by intercalation with Ru(bpy)dppz was investigated using the atomic force microscopy.

Polymer-free electrospinning of tannic acid and cross-linking in water for hybrid supramolecular nanofibres.

Electrospinning is the process of choice allowing the preparation of nanofibrous materials from a solution usually based on a high molar mass polymer. The solution must bring enough chain entanglements to avoid any breaking or Rayleigh instability of the electrospun jet resulting thus in the deposition of a continuous and regular solid nanofibre. It has been however shown that some few non-polymeric molecules can be electrospun without using a carrier polymer.

Holographic Traction Force Microscopy.

Traction Force Microscopy (TFM) computes the forces exerted at the surface of an elastic material by measuring induced deformations in volume. It is used to determine the pattern of the adhesion forces exerted by cells or by cellular assemblies grown onto a soft deformable substrate. Typically, colloidal particles are dispersed in the substrate and their displacement is monitored by fluorescent microscopy.

Geometrical instability in the imbibition of a sphere.

We study the imbibition of a spherical porous aggregate. When the difference in pressure between the inside and the outside of the aggregate is large enough, the imbibition front becomes unstable. This instability leads to the acceleration of the imbibition process.

Investigation on the pitting of potato starch granules during high frequency ultrasound treatment.

In this paper, the pitting of potato starch granules in aqueous suspensions (1%) by high-frequency high-power ultrasound (850kHz at a power of 0.2W, 2W or 3.7W; and also 500kHz and 1MHz at a power of 2W) is reported.

Flexibility of short ds-DNA intercalated by a dipyridophenazine ligand.

We use Förster Resonant Energy Transfer (FRET) in order to measure the increase of flexibility of short ds-DNA induced by the intercalation of dipyridophenazine (dppz) ligand in between DNA base pairs. By using a DNA double strand fluorescently labeled at its extremities, it is shown that the end-to-end length increase of DNA due to the intercalation of one dppz ligand is smaller than the DNA base pair interdistance. This may be explained either by a local bending of the DNA or by an increase of its flexibility.

Complexation of DNA with ruthenium organometallic compounds: the high complexation ratio limit.

Interactions between DNA and ruthenium organometallic compounds are studied by using visible light absorption and circular dichroism measurements. A titration technique allowing for the absolute determination of the advancement degree of the complexation, without any assumption about the number of complexation modes is developed. When DNA is in excess, complexation involves intercalation of one of the organometallic compound ligands between DNA base pairs.

UV-vis absorption spectrum of a novel Ru(II) complex intercalated in DNA: [Ru(2,2'-bipy)(dppz)(2,2'-ArPy)]⁺.

The synthesis of a new Ru(II) complex is reported. Its absorption spectrum when interacting with DNA in water was calculated at the hybrid quantum mechanics molecular mechanics level of theory and compared with experimental data. The vertical transitions were computed using time-dependent density functional theory in the linear response approximation.

Induction of caspase 8 and reactive oxygen species by ruthenium-derived anticancer compounds with improved water solubility and cytotoxicity.

Organometallic compounds which contain metals, such as ruthenium or gold, have been investigated as a replacement for platinum-derived anticancer drugs. They often show good antitumor effects, but the identification of their precise mode of action or their pharmacological optimization is still challenging. We have previously described a class of ruthenium(II) compounds with interesting anticancer properties.

Spectral properties of polypyridyl ruthenium complexes intercalated in DNA: theoretical insights into the surrounding effects of [Ru(dppz)(bpy)2]2+.

The UV/Visible absorption properties of a polypyridyl ruthenium complex upon intercalation on DNA are studied at the mixed quantum mechanics molecular mechanics level of theory. Vertical excitation transitions are computed by time dependent density functional theory. Particular emphasis is put on the different levels at which the macromolecular environment is treated, and in particular on the analysis of the effect of mechanical, electrostatic and polarizable embedding.

Quantification of high-power ultrasound induced damage on potato starch granules using light microscopy.

A simple light microscopic technique was developed in order to quantify the damage inflicted by high-power low-frequency ultrasound (0-160 W, 20 kHz) treatment on potato starch granules in aqueous dispersions. The surface properties of the starch granules were modified using ethanol and SDS washing methods, which are known to displace proteins and lipids from the surface of the starch granules. The study showed that in the case of normal and ethanol-washed potato starch dispersions, two linear regions were observed.

DNA binding to an anticancer organo-ruthenium complex.

Because many anticancer drugs interact with DNA, the determination of their association constants to DNA is essential for quantifying their mechanisms of action. The interactions between a new ruthenium-derived compound [ruthenium(phenanthroline)(κ-C,N-(2-phenyl-pyridine)(NCMe)(2)]PF(6), called RDC11] and DNA are studied using different techniques. Fluorescent experiments are used to determine the association and dissociation constants under different salt concentrations.

Contact and stress anisotropies in start-up flow of colloidal suspensions.

Spatiotemporal correlations in start-up flows of attractive colloids are explored by numerical simulations as a function of their volume fraction and shear rate. The suspension is first allowed to flocculate during a time tw, then the stress necessary to induce its flow is computed. We find that, at low volume fractions, the stress is a universal function of the strain.

A ruthenium-containing organometallic compound reduces tumor growth through induction of the endoplasmic reticulum stress gene CHOP.

Cisplatin-derived anticancer therapy has been used for three decades despite its side effects. Other types of organometallic complexes, namely, some ruthenium-derived compounds (RDC), which would display cytotoxicity through different modes of action, might represent alternative therapeutic agents. We have studied both in vitro and in vivo the biological properties of RDC11, one of the most active compounds of a new class of RDCs that contain a covalent bond between the ruthenium atom and a carbon.

Formation and self-organization kinetics of alpha-CD/PEO-based pseudo-polyrotaxanes in water. A specific behavior at 30 degrees C.

alpha-Cyclodextrins (alpha-CDs) have the ability to form inclusion complexes with poly(ethylene oxide) (PEO) polymer chains. These pseudo-polyrotaxanes (PPRs) can be obtained by quenching an alpha-CD/PEO mixture in water from 70 degrees C down to a lower temperature (typically in the range from 5 to 30 degrees C) thanks to favorable interactions between alpha-CD cavities and PEO chains. Moreover, starting from a liquid alpha-CD/PEO mixture at a total mass fraction of 15% w/w at 70 degrees C, the formation of PPRs with time at a lower temperature induces a white physical gel with time, and phase separation is observed.

Relaxation of jammed colloidal suspensions after shear cessation.

The dynamics of heterogeneities in a shear thickening, concentrated colloidal suspension is investigated through speckle visibility spectroscopy, a dynamic light scattering technique recently introduced [P. K. Dixon and D.

Dilatant flow of concentrated suspensions of rough particles.

The flow anisotropy of a concentrated colloidal suspension at the jamming transition is studied. It is shown that the use of rough spherical particles reduces the hydrodynamic lubrication forces between adjacent colloids and makes possible the study of the stress tensor anisotropy. At low shear rates, the suspension exerts an attractive force between two opposite surfaces, whereas at higher shear rates it becomes dilatant.