Fast dissolving nanofibrous matrices prepared by electrospinning of polyaspartamides

Owing to their versatile chemistry, polyaspartamides have recently attracted increased interest in various biomedical uses such as drug delivery systems and scaffolding materials. Their solubility in organic solvents and in water at different values of pH can be fine-tuned by the chemical composition of these polymers, which was here exploited to fabricate fast-dissolving electrospun matrices in ethanol with no additives.

Various side groups were tested to control the solubility of the polymers as well as the morphology and moisture uptake of the matrices produced. Tertiary amine groups were immobilized to ensure high solubility around neutral pH, while modification with alkyl side groups limited moisture uptake. Finally, 3–(diethylamino)propyl and n-butyl side groups were used in equal amounts.

The effect of viscosity, surface tension and specific conductivity of polymer solutions on the fiber morphology was determined in order to optimize the conditions for preparing fibers with a narrow size distribution and large specific surface area. The polymer withstood the electrospinning process without any chemical degradation, as determined by IR, and was thermally stable.

Furthermore, the matrices exhibited a glass transition temperature above room temperature. Rapid release of the active compound is anticipated due to the fast dissolution of the matrices in oral cavity as it was demonstrated by the complete release of vitamin B₁₂ within one minute from the matrix in simulated salivary fluid at pH = 6.8.

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