Preserved Silk Protein Fragment Compositions and Articles Manufactured Therefrom

A composition comprising silk fibroin protein or fragments thereof, lemongrass essential oil, and water;

• wherein the composition is in the form of a solution;
• wherein the pH of the solution is less than about 7.0;
• wherein the silk fibroin protein or fragments thereof have a weight average molecular weight range of about 5 kDa to about 144 kDa;
• and
• wherein the solution exhibits a fungal count of less than 100 CFU/mL when stored for a period of time selected from the group consisting of 3 months, 6 months, 1 year, 2 years, and 3 years.

A composition comprising silk fibroin protein or fragments thereof and water;

• wherein the composition is in the form of a solution;
• wherein the pH of the solution is between about 1.0 and about 4.0;
• wherein the silk fibroin protein or fragments thereof have a weight average molecular weight range of about 5 kDa to about 144 kDa;
• wherein the solution exhibits a fungal count of less than 100 CFU/mL when stored for a period of time selected from the group consisting of 3 months, 6 months, 1 year, 2 years, and 3 years;
• and
• wherein the solution exhibits a bacterial count of less than 100 CFU/mL when stored for a period of time selected from the group consisting of 6 months, 1 year, 2 years, and 3 years.

A composition comprising a first preservative, a second preservative, and water;

• wherein the first preservative is silk fibroin protein or fragments thereof;
• wherein the composition is in the form of a solution;
• wherein the second preservative is selected from the group consisting of Aspen bark extract, potassium sorbate, sodium anisate, magnesium salicylate, lemongrass essential oil, and any combination thereof;
• wherein the silk fibroin protein or fragments thereof have a weight average molecular weight range of about 5 kDa to about 144 kDa;
• wherein the solution exhibits a fungal count of less than 100 CFU/mL when stored for a period of time selected from the group consisting of 3 months, 6 months, 1 year, 2 years, and 3 years;
• and
• wherein the solution exhibits a bacterial count of less than 100 CFU/mL when stored for a period of time selected from the group consisting of 3 months, 6 months, 1 year, 2 years, and 3 years.

A method of preserving a composition comprising the steps of:

• (a) providing a first preservative comprising a quantity of silk fibroin protein or fragments thereof, wherein the silk fibroin protein or fragments thereof have a weight average molecular weight range of about 5 kDa to about 144 kDa;
• (b) dissolving the silk fibroin protein or fragments thereof to form an aqueous solution;
• (c) optionally adjusting the pH of the aqueous solution to between about 1.0 and about 4.0;
• (d) optionally adding a second preservative, wherein the second preservative is selected from the group consisting of Aspen bark extract, potassium sorbate, sodium anisate, magnesium salicylate, lemongrass essential oil, and any combination thereof;
• (e) storing the aqueous solution for a period of time selected from the group consisting of 6 months, 1 year, 2 years, and 3 years, wherein after the storage period, the aqueous solution exhibits a bacterial count of less than 100 CFU/mL and a fungal count of less than 100 CFU/mL.

A method of forming a preserved gel comprising the steps of:

• (a) providing a first preservative comprising a quantity of silk fibroin protein or fragments thereof, wherein the silk fibroin protein or fragments thereof have a weight average molecular weight range of about 5 kDa to about 144 kDa;
• (b) dissolving the silk fibroin protein or fragments thereof to form an aqueous solution;
• (c) inducing the aqueous solution to form a gel using a nucleating agent;
• (d) folding a second preservative into the gel, such that the gel and the second preservative powder are substantially homogeneous;
• (e) storing the gel for a period of time selected from the group consisting of 6 months, 1 year, 2 years, and 3 years, wherein after the storage period, the gel exhibits a bacterial count of less than 100 CFU/mL.