Periodontal disease is a widespread chronic inflammatory gum disease for which the currently existing treatment does not guarantee permanent positive results in case of all patients. Consequently, nanomedicines are in development to achieve more effective treatment. The goal of this Master’s thesis was to design polycaprolactone nanofibers with metronidazole with a therapeutic dose, to evaluate and compare them with a film that was made with the same composition as the nanofibers.
We electrospun nanofibers and studied the effects of different collection parameters on the homogeneity of the obtained sample by measuring the nanofiber layer thickness and conducting tests in accordance with Ph. Eur. 10.0 (Uniformity of mass of single-dose preparations, Uniformity of content of single-dose preparations, Uniformity of dosage units). The films were made by solution casting method and the morphology of both delivery systems was evaluated by scanning electron microscopy. We also studied the residual solvents in nanofibers, the metronidazole release by a validated UPLC method and the bioadhesivity of the prepared formulations.
Results have shown that with longer time of electrospinning we could prepare thicker and heavier nanofiber mat. The most homogeneous nanofiber layer was obtained by collecting a sample on a rotating cylinder, since only in this case the mass uniformity test was conformed. The metronidazole incorporation into nanofibers was successful with an average content of 100.0%. The formulations collected on the cylinder and on the plate corresponded to the uniformity of content and uniformity of dosage units tests, since the content level for all tested units ranged from 85 to 115%, and the AV value was lower than 15.0. The drying of nanofibers is an important step in production, since it enabled the reduction of the residual solvents in the sample below the detection limit. Such nanofibers also resulted in a slower release of metronidazole as before drying. A slower release was also attained at a lower temperature of the medium and from a thicker nanofiber layer. Meanwhile, the release of the metronidazole from the film was faster when compared to the nanofibers. There were no significant differences in the bioadhesive properties of the two formulations, although the nanofibers demonstrated a higher level of resistance towards mechanical stress. Therefore, this Master’s thesis proves that by optimising the processing parameters of electrospinning, we can produce homogeneous, bioadhesive, mechanically resistant nanofibers with prolonged drug delivery.