Stability of nasal insulin solutions containing sorption promoters

The purpose of this study was to investigate the stability of nasal insulin solutions containing sorption promoters. The absorption enhancers used in the preparations were; sodium glycocholate (GLI), sodium deoxycholate (DEO) , polyoxyethylene-8-lauryl ether (POE-8), polyoxyethylene-9-lauryl ether (P OE-9) and L-alpha -lysophosphatidylcholine (Lyso) in 1% (w/v) concentration s. Investigated solutions were stored at temperatures of 5, 20 and 37 degre esC. During the course of the study, the following analyses were performed: visible assessment of the preparations, pH and viscosity measurements, vis ible light absorbance as well as a determination of insulin and desamidoins ulin concentrations.