1. Coaxial needle less electrospinning Ing. Lucie Vysloužilová Prof. RNDr. David Lukáš, CSc. Ing. Lucie Vysloužilová Prof. RNDr. David Lukáš, CSc.

2. Coaxial electrospinning  Special method for bicomponent core/shell nanofibers production  Shell – mostly polymer material  Core – polymer of nonpolymer material, liquid, encapsulated materials  Hollow nanofibers  Possibility of nonspinnable  materials electrospinning core shell

3. Coaxial needle electrospinning  Droplet, one Taylor cone, one polymer jet  Low productivity a) co-axial spinner b) feeding of shell material c) feeding of core material d) drop e) polymer jet f) grounded collector

4. Coaxial needle less electrospinning  Polymeric bi-layer  More Taylor cones more polymer jets  Procutivity increasment a) layer of „core“ material b) layer of „shell“ material c, d) Taylor cone e) polymer jet f) grounded collector g) high electrical voltage source

5. Coaxial needle less electrospinning -basin  Shell: 12% PVA  Core: oil 12%PVA/oil12%PVA+dye/oil

6. Optical microscope  Basin from nonconductive material  Shell: 12% PVA + dye  Core: oil

7. Optical microscope  Basin from nonconductive material  Shell: 12% PVA + dye  Core: oil 50 µm

8. Weir spinner  A new device for bicomponent nanofibers production  Needle-less electrospinning  Principle: the bi-layer overflowing through electrode

9. (a) Weir spinner (b) Holder (c) Feeding of shell material (d) Feeding of core material (e) Holder of cable from high voltage source Weir spinner

10.  Shell: 12% PVA + dye + rhodamin  core: 10% PVA + fitc dextran

11. Confocal scanning microscopy 100 µm Core:10% PVA + rhodaminShell: 12% PVA + fitc dextran

12. Advantages of needle-less coaxial electrospinning technology  Production of bicomponent core/shell nanofibers  Production of hollow fibers  Encapsulation – drug delivery systems  Electrospinning of nonspinnable materials by common electrospinning technology  Increasing productivity  Easy cleaning of the spinner

13. Thank you for your attention!