All the other products exhibited a lower diffusion activity with a mild to moderate impregnation effect. The diffusion experiments showed a high diffusion efficacy along with a high impregnation effect for one test product. ResultsĬanine cerumen is mainly composed of triglycerides, sterol esters, fatty acid esters and squalene. A second in-vitro experiment determined both the ceruminolytic activity and impregnation effect of the otic preparations by comparing the weight loss or weight gain after repeated incubation of JSL. The diffusion activities of the otic preparations through both types of synthetic cerumen were studied over 24 hours.

A synthetic cerumen described in the literature (JSL) was also used for comparison as its lipid composition was different to SCC. These two marker compounds (Oil red O and marbofloxacin) were chosen, since they exhibit different physicochemical drug characteristics by which it is possible to determine and verify the diffusion activity of different types of liquids (i.e. SCC was filled into capillary tubes, all of which were loaded with six commercially available multipurpose otic medications and two ear cleaners, each mixed with two markers in two experimental setups. The main lipid classes of canine cerumen produced with moderate, non-purulent otitis externa were determined by thin layer chromatography and were subsequently used to produce a standardised synthetic cerumen (SCC).

An in-vitro setup was established in order to determine a) the diffusion activities of eight otic preparations (Aurizon®, Eas Otic®, Epi Otic®, Otifree®, Otomax®, Panolog®, Posatex®, Surolan®) through synthetic cerumen, and b) the ceruminolytic capacity and impregnation effects of these products.

Otomax dogs