Storage stability of silk solution for viscosity and electrospinnability

In the present study, silk fibroin (SF) was dissolved in CaCl 2 /H 2 O/EtOH solution at 85 o C. After the dissolution, the SF solution was cooled down and stored at 4 o C for 28 d. The stability of the solution’s viscosity and electrospinnability was observed to examine the stability of SF molecules during storage in CaCl 2 /H 2 O/EtOH solution. The viscosities of SF/CaCl 2 /H 2 O/ EtOH solution and SF formic acid solution did not change during 28 days’ storage of SF in CaCl 2 /H 2 O/EtOH solution. The electrospinnability of the SF solution, mean diameter of the electrospun SF fiber, and crystallinity index of electrospun SF web did not change, regardless of the length of the storage period. These results imply that SF molecules do not degrade during 28 days’ storage in CaCl 2 /H 2 O/EtOH solution.