Using different structure types of microemulsions for the preparation of poly(alkylcyanoacrylate) nanoparticles by interfacial polymerization

Characterization of microemulsion structures in the pseudoternary phase diagram of isopropyl palmitate/water/Brij 97:1-butanol

This research was aimed to characterize microemulsion systems of isopropyl palmitate (IPP), water, and 2:1 Brij 97 and 1-butanol by different experimental techniques. A pseudoternary phase diagram was constructed using water titration method. At 45% wt/wt surfactant system, microemulsions containing various ratios of water and IPP were prepared and identified by electrical conductivity, viscosity, differential scanning calorimetry (DSC), cryo-field emission scanning electron microscopy (cryo-FESEM) and nuclear magnetic resonance (NMR). The results from conductivity and viscosity suggested a percolation transition from water-in-oil (water/oil) to oil-in-water (oil/water) microemulsions at 30% wt/wt water. From DSC results, the exothermic peak of water and the endothermic peak of IPP indicated that the transition of water/oil to oil/water microemulsions occurred at 30% wt/wt water. Cryo-FESEM photomicrographs revealed globular structures of microemulsions at higher than 15% wt/wt water. In addition, self-diffusion coefficients determined by NMR reflected that the diffusability of water increased at higher than 35% wt/wt water, while that of IPP was in reverse. Therefore, the results from all techniques are in good agreement and indicate that the water/oil and oil/water transition point occurred in the range of 30% to 35% wt/wt water.

Application of pharmaceutical drug delivery for biological control of the common brushtail possum in New Zealand: a review

The common brushtail possum (Trichosurus vulpecula) is the most significant vertebrate pest in New Zealand, being a major ecological threat to the indigenous biodiversity and an economic threat as a vector for bovine tuberculosis. Novel and effective strategies to reduce the population of T. vulpecula are needed urgently. Several biocontrol agents are currently being assessed and from research to date it is likely that the biocontrol agents will be peptide or protein molecules. It is not possible to administer such biocontrol agents alone because they would be degraded rapidly in the animal, especially if delivered orally. Technologies used in the pharmaceutical industry to design efficacious drug-delivery systems for humans and animals can be applied to the design of delivery systems for biocontrol agents used in wildlife management, although there are some unique challenges that must be overcome.