A sensitive electrochemical DNA biosensor for detecting the genome of a plant growth-promoting bacteria.

The challenge of increasing food production while maintaining environmental sustainability can be addressed by using biofertilizers such as Azospirillum, which can enhance plant growth and colonize more than 100 plant species. The success of this biotechnology depends on the amount of plant growth-promoting bacteria associated with the plant during crop development. However, monitoring bacterial population dynamics after inoculation requires time-consuming, laborious, and costly procedures.

Nanoarchitectonics and Simulation on the Molecular-Level Interactions between Sulfonic Acid Calix[4]arene and Langmuir Monolayers Representing Healthy and Cancerous Cell Membranes.

The design of chemotherapeutic drug carriers requires precise information on their interaction with the plasma membrane since the carriers should be internalized by cells without disrupting or compromising the overall integrity of the membrane. In this study, we employ Langmuir monolayers mimicking the outer leaflet of plasma membranes of healthy and cancerous cells to determine the molecular-level interactions with a water-soluble calixarene derivative, -sulfonic acid calix[4]arene (SCX4), which is promising as drug carrier. The cancer membrane models comprised either 40% 1,2-dipalmitoyl--glycero-3-phosphocholine (DPPC) or 1,2-dioleoyl--glycero-3-phosphocholine (DOPC), 30% cholesterol (Chol), 20% 1,2-dipalmitoyl--glycero-3-phosphoethanolamine (DPPE), and 10% 1,2-dipalmitoyl--glycero-3-phospho-l-serine (DPPS).

Study of brine-halite phase separation through optical constringence and molecular dynamics.

This work presents a study of the reciprocal dispersive power, also known as constringence or Abbe number of an aqueous solution of NaCl in a wide range of concentrations. The constringence exhibited a distinct behavior in the region close to the phase transition between a phase containing exclusively brine and a phase containing brine+halite. Molecular dynamics simulations of this system indicated the existence of halite formation below the known saturation curve, which agreed with the experimental measurements, indicating a crystal growth in the unsaturated region.

The antibacterial activity of p-tert-butylcalix[6]arene and its effect on a membrane model: molecular dynamics and Langmuir film studies.

The antibacterial activity of a calixarene derivative, p-tert-butylcalix[6]arene (Calix6), was assessed and was shown not to inhibit the growth of E. coli, S. aureus and B.

An experimental and theoretical study of the aggregate structure of calix[6]arenes in Langmuir films at the water/air interface.

In this paper, the aggregate formation of para-tert-butylcalix[6]arene molecules (Calix6) in dimeric structures was investigated at the water/air interface using experimental and theoretical studies. A specific orientation for such Calix6 molecules was observed with an average area of 133 Å(2), which corresponds to a flat-on orientation with the OH groups parallel to the interface. By varying the pressure on the Calix6 monolayer, the molecules tend to organize at the water/air interface and subsequently, at higher pressures, aggregates were formed atop the monolayer as cluster structures.

Molecular dynamics studies of aqueous silica nanoparticle dispersions: salt effects on the double layer formation.

The ion distribution around hydroxylated silica nanoparticles (NP-H) dispersed in brine was investigated by fully atomistic molecular dynamics. The NP-H dispersions in aqueous electrolyte media are simulated in solutions of varying salinity (NaCl, CaCl2, and MgCl2), salt concentration (0.06  ×  10(-3) to 3.

Molecular dynamics studies of fluid/oil interfaces for improved oil recovery processes.

In our paper, we study the interface wettability, diffusivity, and molecular orientation between crude oil and different fluids for applications in improved oil recovery (IOR) processes through atomistic molecular dynamics (MD). The salt concentration, temperature, and pressure effects on the physical chemistry properties of different interfaces between IOR agents [brine (H(2)O + % NaCl), CO(2), N(2), and CH(4)] and crude oil have been determined. From the interfacial density profiles, an accumulation of aromatic molecules near the interface has been observed.

Interface tension of silica hydroxylated nanoparticle with brine: a combined experimental and molecular dynamics study.

We have used molecular dynamics simulations to calculate the interfacial tension of hydroxylated SiO(2) nanoparticles under different temperatures and solutions (helium and brine with monovalent and divalent salts). In order to benchmark the atomistic model, quartz SiO(2) interfacial tension was measured based on inverse gas chromatography under He atmosphere. The experimental interfacial tension values for quartz were found between 0.