alcohol, chloroform, acetonitrile and practically insoluble in water, benzol, toluol and
hexane
[5].
The particularities of the prophylaxis and management of the diabetes skin lesions
limit the conditions of the development of pharmaceutical combination for local
administration. The requirements for topical pharmaceutical compositions suitable for
diabetic patients as follows:
−
to have softening and moisturizing effects;
−
mustn’t contain allergens or irritating components;
−
doesn't cause redness of the skin and violation of the gas and heat exchange;
−
to have good consumer's characteristics (colour, smell, viscosity,
spreadability, etc);
−
doesn't cause discomfort while applying and removing from the skin.
Therefore, the topical pharmaceutical compositions based on o/w emulsion or gels
based on carbopol polymers have to be objects of the investigation.
Nowadays, pharmaceutical gels useful for topical administration have good
viscosity and absorbability and are more preferable than other soft formulations.
However, the aqueous gels based on carbopol are prepared using neutralization of the
acid colloidal solutions with sodium hydroxide or triethanolamine to neutral or slight
alkaline pH. It means that rheological behaviour and quality of base depends on pH.
Taking into account the SAD chemical structure and its property to be hydrolyzed in
pH up to 7, the methods preparing of soft pharmaceutical forms with neutralization
have to be studiedcarefully.
The pharmaceutical emulsion bases with cooling, softening, moisturizing and
reducing itching effects have been considered to be the most perspective. The presence
in the emulsion bases the surface -active substances (Sodium Lauryl Sulfate,
Span®
,
tweens) which influence the cells membrane’s permeability and increase bioactive
substance's absorbability, promotes the effectiveness of the soft pharmaceutical dosage
form. It is considered, that high permeability of the active pharmaceutical ingredient
from emulsion bases depends on hydrating action of water contained in these types of
the ointment base systems. Water is intensively absorbed by proteins of the surface
layers of skin. The presence of water impacts on the penetration of the active
components into the deepest skin layers. These fixed characteristics of the emulsion
base are suitable for topical treatment of skin lesion in diabetic patients.
To achieve the perfect pharmacological effect of soft pharmaceutical forms for
topical appliance the active pharmaceutical ingredient has to be freely soluble in base
or must have appropriate particles size. SAD is practically insoluble in water and has
bad permeability through the skin, but it is soluble in dimethylsulfoxide. Taking into
account some positive properties of this solvent such as antiseptic, fibrinolytic,
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