presi dal brevetto prima citato:
Ci sono alcuni esempio di formulazione con diversi componenti
Esempio 1 con FINASTERIDE
Esempio 2 con DUTASTERIDE
Esempio 3 con MINOXIDIL
Esempio 4 con SPIRONOLACTONE
In fondo dice che:
“Si conclude che finasteride è stato in grado di permeare la pelle di ratto, dopo l'applicazione della soluzione di formare pellicola di idrossipropil chitosano secondo l'esempio 1, in modo rapido e duraturo”
EXAMPLE 1
• [0021]
A film forming solution having the following composition wt./wt.% was prepared:
1) Finasteride 0.25%
2) Ethyl Alcohol 96° 55.00%
3) Propylene Glycol 5.00%
4) Hydroxypropyl Chitosan 1.00%
5) Purified water 38.75%
Preparation
• [0022]
Ethyl Alcohol, Propylene Glycol and water were mixed at room temperature. Finasteride was then added and mixed until a clear solution was obtained. Hydroxypropyl Chitosan was added as the final ingredient, and the mixture was stirred at room temperature for 24 hours or until dissolution.
• [0023]
The obtained formulation was a clear and colourless solution, homogenous in appearance even after prolonged storage. Moreover, the liquid was able to form a matte, non-sticky and elastic film, which could strongly adhere to the scalp surface.
EXAMPLE 2
• [0024]
A liquid formulation having the following w/w % composition was prepared:
1) Dutasteride 0.25%
2) Ethyl Alcohol 96° 55.00%
3) Propylene Glycol 5.00%
4) Hydroxypropyl Chitosan 2.00%
5) Purified water 37.75%
Preparation
• [0025]
The formulation was prepared by using the same method described for Example 1.
• [0026]
Hydroxypropyl Chitosan was added as the final ingredient, and the mixture was stirred at room temperature for 24 hours or until dissolution.
• [0027]
The obtained formulation was a clear and colourless solution, homogenous in appearance even after prolonged storage. Moreover, the liquid was able to form a matte, non-sticky and elastic film, which could strongly adhere to the scalp surface.
EXAMPLE 3
• [0028]
A liquid formulation having the following w/w % composition was prepared:
1) Minoxidil 2.00%
2) Ethyl Alcohol 96° 55.00%
3) Propylene Glycol 5.00%
4) Hydroxypropyl Chitosan 1.00%
5) Purified water 37.00%
Preparation
• [0029]
The formulation was prepared by using the same method described for Example 1.
• [0030]
Hydroxypropyl Chitosan was added as the final ingredient, and the mixture was stirred at room temperature for 24 hours or until dissolution.
• [0031]
The obtained formulation was a clear and colourless solution, homogenous in appearance even after prolonged storage. Moreover, the liquid was able to form a matte, non-sticky and elastic film, which could strongly adhere to the scalp surface.
EXAMPLE 4
• [0032]
A liquid formulation having the following w/w % composition was prepared:
1) Spironolactone 1.00%
2) Ethyl Alcohol 96° 55.00%
3) Propylene Glycol 5.00%
4) Hydroxypropyl Chitosan 2.00%
5) Purified water 37.00%
Preparation
• [0033]
The formulation was prepared by using the same method described for Example 1.
• [0034]
Hydroxypropyl Chitosan was added as the final ingredient, and the mixture was stirred at room temperature for 24 hours or until dissolution.
• [0035]
The obtained formulation was a clear and colourless solution, homogenous in appearance even after prolonged storage. Moreover, the liquid was able to form a matte, non-sticky and elastic film, which could strongly adhere to the scalp surface.
EXAMPLE 5
• [0036]
An in vitro permeation test was performed by applying the film forming solution according to the Example 1 to excised hairless rat skin, obtained from dorsal or abdominal skin of male hairless rats. Portions of the skin (ca 9 cm2), after removal of adhering fat and subcutaneous tissues, were placed as a barrier between the two compartment of Gummer permeation vertical cells (Gummer, C.L. et al. The skin penetration cell: design update. Int. J. Pharm. 1987, 40, 101-104). The receiving phase was introduced into the lower compartment and 1.0 or 0.5 mL of the composition according to the Example 1 were regularly distributed on the exposed skin surface. At predetermined time intervals (2, 4, 8, 12, 16, 20 and 24 hours) 5.0 mL of the receiving solution were collected for analysis and immediately replaced by an equal volume of fresh buffer. The experiment was replicated 3 times.
• [0037]
The finasteride permeated through hairless rat skin in the 3 experiments is reported in Figure 1. The total percent quantity (Q%) permeated through the rat hairless skin was 6.59 ± 1.90% for the 1.0 mL dose and 8.78 ± 1.33% for the 0.5 mL dose.
• [0038]
It is concluded that finasteride was able to permeate the rat skin, after the application of the film forming solution of hydroxypropyl chitosan according to the Example 1, in a quick and long lasting way.
