engleski

Chitosan-based microspheres prepared by electrospraying

Electrospraying is a method based on the formation of positively charged liquid droplets due to applied high voltage and as such is used to produce polymeric microspheres. In this work, chitosan which is biocompatible, biodegradable and non-toxic biopolymer was used as a polymer matrix. The important process parameters for obtaining chitosan-based microspheres are voltage (kV), a needle gauge and a distance between the needle tip and the collector. Moreover, the properties of chitosan (degree of deacetylation, DD, concentration and flow rate of the polymer solution), and the concentration of acetic acid are also determining parameters. Furthermore, chitosan solution was modified using copper(II) and zinc(II) ions, which are used in tissue engineering due to favourable properties like enhancing of angiogenesis, proliferation of cells and bone formation. The aim of this work was to investigate the influence of chitosan’s degree of deacetylation and applied electrical field on the size, shape and microstructure of prepared microspheres. The parameters such as the needle gauge (21 G), the distance between the needle tip and the collector (10 cm), the chitosan concentration (1.2 % w/v), the flow rate (5 mL h-1) and the concentration of acetic acid (0.5 %) were kept constant. The chitosan’s DD was 75 % or 95 %, and applied voltage 20 kV or 25 kV. The prepared wet microspheres were neutralised with 1 % solution of ammonia and washed with distilled water. Obtained microspheres were characterised by light and scanning electron microscopy in terms of size and microstructure. The preliminary results show porous, spherical structure and narrow size distribution of microspheres produced at 25 kV voltage and with chitosan characterised by DD = 75 %. Future experiments will be focused on investigating the other process parameters (needle gauge and distance between the needle and collector) on the properties of chitosan-metal ion microspheres.

Chitosan, copper, zinc, microspheres, electrospraying.

nije evidentirano