Method development for the clearance study of the Pluronic F-68 nonionic surfactant used in the upstream process of monoclonal antibody production.

Pluronic F-68 is a nonionic surfactant, which is often used in the upstream process of biopharmaceutical production. However, the number of analytical methods developed for determination of Pluronic F-68 in the in-process and drug substance samples of biological drug production process is quite low. The lack of chromophore groups on the molecule and the interference caused by the high protein content of the samples hamper analysis.

Toxicity mitigation by N-acetylcysteine and synergistic toxic effect of nano and bulk ZnO to Panagrellus redivivus.

To better understand the nanosize-relevant toxic effects and underlying mechanisms, N-acetylcysteine (NAC), as a mitigation agent, an ionic form of Zn (ZnCl), and the binary mixture of ZnO with different particle sizes (15 nm and 140 nm), was used in toxicity assays with the nematode Panagrellus redivivus. The ZnCl concentrations were applied to show the amount of dissolved Zn ions present in the test system. Reactive oxygen species (ROS) measuring method was developed to fit the used test system.

Toxicity and uptake of nanoparticulate and bulk ZnO in nematodes with different life strategies.

Despite the increasing number and quantity of nanomaterials released in the environment, our knowledge on their bioavailability and possible toxicity to organisms is rather limited. Thus, we know quite little about sensitivity of various nematode feeding types and life strategies to treatments with nano metal oxides. The toxicity of zinc oxide nanoparticles (nano-ZnO) (with a particle size of 25 nm) and the bulk counterpart was investigated in two free-living nematode species of different life strategies: Xiphinema vuittenezi, a K-strategist plant-feeder nematode and Panagrellus redivivus, an r-strategist bacterivor nematode.

Uptake and toxicity of nano-ZnO in the plant-feeding nematode, Xiphinema vuittenezi: the role of dissolved zinc and nanoparticle-specific effects.

Nanoparticulate ZnO is one of the most commonly applied nanomaterials. As ZnO is more soluble than many other oxide nanoparticles, its toxicity beyond the nanoparticle-specific effects can be attributed to the dissolved ionic zinc. The investigation of uptake and toxicity of nano-ZnO in the plant-feeding nematode, Xiphinema vuittenezi, which was used in previous studies as a biological model organism, was aimed.

The role of stabilization centers in protein thermal stability.

The definition of stabilization centers was introduced almost two decades ago. They are centers of noncovalent long range interaction clusters, believed to have a role in maintaining the three-dimensional structure of proteins by preventing their decay due to their cooperative long range interactions. Here, this hypothesis is investigated from the viewpoint of thermal stability for the first time, using a large protein thermodynamics database.