الفهرس 
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Abstract
Simvastatin is a lipid-lowering agent that competitively inhibits hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase, which is essential for the conversion of HMG-CoA to mevalonate, an essential step in cholesterol production. The drug simvastatin has also gained great interest due to its effectiveness in significantly accelerating the wound healing process, which was shown in increasing the formation of lymphatic vessels. The drug also enhanced the infiltration of macrophages, resulting in the production of vascular endothelial growth factor C in granulation tissue. In addition to its direct role in the formation of blood capillaries in the laboratory and preventing lymphatic endothelial cells from dying. Due to its broad spectrum of pleiotropic effects, simvastatin may be considered a unique therapeutic approach for a variety of disease conditions, including psoriasis, sepsis, alopecia, wound healing, and other inflammatory diseases.
For this reason, simvastatin is used topically to speed up and improve the wound healing process. Because simvastatin is poorly soluble in water (30 mcg/ml) and dissolution is an important step for the absorption and distribution process, solubility was improved before developing and making membranes containing it in order to achieve maximum benefit. More than one polymer was applied to achieve the best result that makes the spare part usable and easy to use.
Polymeric membranes act as a physical barrier between the wound and the external environment and are therefore essential for wound healing. Traditional films, such as gauze, may adhere to newly formed granulation tissue and be difficult to remove. Moreover, it does not contain antibacterial, antioxidant or any other properties. As a result, there is a need for biodegradable wound membranes based on bioactive materials that can promote extracellular matrix deposition and promote wound healing. It has been observed that polymeric membranes improve therapeutic efficacy by accelerating the initial healing phase, reducing dose frequency, and eliminating side effects.
Wound films made of polymer are biocompatible with the nature of the skin, have excellent mechanical properties and adequate adhesion, maintain the environment moist enough for cell migration and encourage their growth, in addition to being completely biodegradable, and no by-products are created. Polymeric membranes are formed either through chemical or physical bonds. The polymer used in manufacturing membranes may be natural materials such as chitosan, collagen, cellulose and starch, or it may be prepared from manufactured materials such as acrylamide and polyethylene glycol. The membranes are prepared by solvent casting, which is the easiest and most effective method, as simple tools and equipment are used and limited manufacturing steps are made, with the possibility of obtaining various shapes of these membranes.
Therefore, the scope of our work includes studying the solubility of simvastatin in different solvents and determining the best polymer to be used in preparing wound films loaded with simvastatin in order to predict the ideal formulation. The compatibility between simvastatin and the different polymers and formulations used in the formulation was also studied, the effect of some different independent variables on the properties of the resulting dressings was studied, and the physical properties of the different formulations were compared. Finally, we estimate the extent of the effect of these manufactured membranes on wound healing in mice.