Dizajn, razvoj i vrednovanje novih nanoemulzija za transdermalnu primjenu celekoksiba

The aim of the present study was to investigate the potential of nanoemulsion formulations for transdermal delivery of celecoxib (CXB). The in vitro skin permeation profile of optimized formulations was compared with CXB gel and nanoemulsion gel. Significant increase in the steady state flux (Jss), permeability coefficient (Kp) and enhancement ratio (Er) was observed in nanoemulsion formulations T1 and T2 (p < 0.05). The highest value of these permeability parameters was obtained in formulation T2, which consisted of 2% m/m of CXB, 10% m/m of oil phase (Sefsol 218 and Triacetin), 50% m/m of surfactant mixture (Tween-80 and Transcutol-P) and 40% m/m of water. The anti-inflammatory effects of formulation T2 showed a significant increase (p < 0.05) in inhibition after 24 h compared to CXB gel and nanoemulsion gel on carrageenean-induced paw edema in rats. These results suggested that nanoemulsions are potential vehicles for improved transdermal delivery of CXB.U radu su opisana ispitivanja nanoemulzija za transdermalnu primjenu celekoksiba (CXB). Profil permeacije kroz kožu ispitivan je in vitro i uspoređivan sa CXB gelom i nanoemulzijskim gelom. U formulacijama T1 i T2 postignuto je značajno povećanje ustaljenog fluksa (Jss), koeficijenta permeabilnosti (Kp) i povećanje omjera (Er) (p < 0.05). Najveće vrijednosti parametara permeabilnosti dobivene su u formulaciji T2 koja je sadržala 2% m/m CXB, 10% m/m uljne faze (Sefsol 218 i Triacetin), 50% m/m površinski-aktivnih tvari (Tween-80 i Transcutol-P) i 40% m/m vode. Protuupalno djelovanje formulacije T2 na edem šape štakora uzrokovan karageninom značajno je povećano (p < 0.05) poslije 24 h u usporedbi sa CXB gelom i nanoemulzijskim gelom. Rezultati ukazuju na poboljšanu isporuku celekoksiba putem nanoemulzija

Water Solubilization Using Nonionic Surfactants from Renewable Sources in Microemulsion Systems

In this study the effect of temperature, NaCl and oils (hydrocarbons: C8–C16) on the formation and solubilization capacity of the systems of oil/monoacylglycerols (MAG):ethoxylated fatty alcohols (CEO20)/propylene glycol (PG)/water was investigated. The effects of the surfactant mixture on the phase behavior and the concentration of water or oil in the systems were studied at three temperatures (50, 55, 60 °C) and with varied NaCl solutions (0.5; 2; 11%). Electrical conductivity measurement, FTIR spectroscopy and the DSC method were applied to determine the structure and type of the microemulsions formed. The dimension of the microemulsion droplets was characterized by dynamic light scattering. It has been stated that the concentration of CEO20 has a strong influence on the shape and extent of the microemulsion areas. Addition of a nonionic surfactant to the mixture with MAG promotes an increase in the area of microemulsion formation in the phase diagrams, and these areas of isotropic region did not change considerably depending on the temperature, NaCl solution and oil type. It was found that, depending on the concentration of the surfactant mixture, it was possible to obtain U-type microemulsions with dispersed particles size distribution ranging from 25 to 50 nm and consisting of about 30–32% of the water phase in the systems. The conditions under which the microemulsion region was found (electrolyte and temperature—insensitive, comparatively low oil and surfactant concentration) could be highly useful in detergency

Microfluidic analysis techniques for safety assessment of pharmaceutical nano- and microsystems

This chapter reviews the evolution of microfabrication methods and materials, applicable to manufacturing of micro total analysis systems (or lab‐on‐a‐chip), from a general perspective. It discusses the possibilities and limitations associated with microfluidic cell culturing, or so called organ‐on‐a‐chip technology, together with selected examples of their exploitation to characterization of pharmaceutical nano‐ and microsystems. Materials selection plays a pivotal role in terms of ensuring the cell adhesion and viability as well as defining the prevailing culture conditions inside the microfluidic channels. The chapter focuses on the hepatic safety assessment of nanoparticles and gives an overview of the development of microfluidic immobilized enzyme reactors that could facilitate examination of the hepatic effects of nanomedicines under physiologically relevant conditions. It also provides an overview of the future prospects regarding system‐level integration possibilities facilitated by microfabrication of miniaturized separation and sample preparation systems as integral parts of microfluidic in vitro models.Non peer reviewe

Pharmaceutical nonionic oil-in-water microemulsions

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN026525 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Formulation development and optimization using nanoemulsion technique: A technical note

Ramipril nanoemulsion formulations were successfully prepared by the spontaneous emulsification method (titration method). Sefsol 218 was selected as the oil phase for the development of the formulation on the basis of the solubility studies. The differences in the droplet size between the formulations selected from the phase diagram was not statistically significant, although the polydispersity was at a minimum for the formulation containing 20% oil, 27% Smix, and 53% vol/vol aqueous phase. The droplet size was found to be 34.5 nm. Therefore, nanoemulsion, a multipurpose technology, can be exploited in drug delivery for poorly soluble drugs. Nanoemulsions have a higher solubilization capacity than simple micellar solutions, and their thermodynamic stability offers advantages over unstable dispersions, such as emulsions and suspensions, because they can be manufactured with little energy input (heat or mixing) and have a long shelf life. This technical note explains the basis for calculation and construction of pseudoternary phase diagrams and, most important, explains selection of the formulations from the phase diagrams to avoid metastable formulations having minimum surfactant concentration in the least possible time