LUNG SURFACTANT COMPOSITIONS WITH DYNAMIC SWELLING BEHAVIOUR

摘要

Lung surfactant compositions capable of forming a dynamic swelling phase when dispersed in a medium containing electrolytes. The dynamic swelling process can be observed by polarising microscopy and results in formation of a birefringerent network or tubules at an air/liquid interface. The dynamic swelling process results in a spreading of the lung surfactant over an increased surface area compared to the spreading of the lung surfactant in a non-dynamic swelling phase. The spreading takes place during a specific span of time after dispersion of a lung surfactant in e.g. a physiological electrolyte solution. Hereby, a more active spreading of the lung surfactant into the alveoli can be obtained after administration to the lungs, which in turn opens the possibility to use such a composition as a carrier for therapeutically, prophylactically and/or diagnostically active substances into the lungs or other organs or body areas that are hard to access. A lung surfactant composition of the invention comprises a lung surfactant, which - when dispersed as powder or particles in 0.9 % w/w sodium chloride in a concentration 10 % w/w at ambient temperature - is capable of forming, in the course of swelling, a birefringent network or tubules at an air-liquid-solid interface within a time period of from about 0.5 min to about 120 min.as observed by polarising microscopy.