Electrospinning Apparatus For Producing Nanofibers and Process Thereof

• US 20090091065A1
• Filed: 10/07/2008
• Published: 04/09/2009
• Est. Priority Date: 10/09/2007
• Status: Abandoned Application

• Current Assignee: Indian Institute of Technology Kharagpur
• Original Assignee: Indian Institute of Technology Kharagpur
• Inventors: Katti, Dhirendra S., Nandan, Amit, Singhal, Riju Mohan
• Application Number:
  US12/246,744
• Publication Number:
  US 20090091065A1
• Time in Patent Office: Days
• US Class Current: 264/465
• CPC Class Codes: D01D 5/0076 characterised by the collecting device, e.g. drum, wheel, endless belt, plate or grid D01D5/0046 takes precedence
• CPC Class Codes: D01D 5/0092 characterised by the electrical field, e.g. combined with a magnetic fields, using biased or alternating fields

Abstract

The present disclosure provides an electrospinning apparatus for producing aligned and crossed nanofibers and method of electrospinning using said apparatus to produce aligned and crossed nanofibers. The electrospinning apparatus comprises of a supported horizontal surface; a DC motor placed below the horizontal surface, a circular rotating disc attached to the DC motor by means of shaft which rotates said disc; a reservoir with an electrospinning element having at least one tip placed perpendicularly above the disc surface, said electrospinning element has a passage by which a substance from which the nanofibers are to be composed is provided to an interior of the tip of the electrospinning element, said electrospinning element configured to electrospin said nanofibers by high voltage mediated extraction of the substance from the tip of the electrospinning element; and at least a focusing device that is positioned exactly below the electrospinning element tip configured to focus the electrospun nanofibers by manipulating the electric field and the disc surface for focusing the electrospun nanofibers into a defined region on the disc surface. The electrospinning element and the focusing device are connected to the opposite terminals of an external high voltage (DC) power supply and face exactly opposite each other.

Claims

1. An electrospinning apparatus 100 for producing aligned and crossed nanofibers, said apparatus comprising,

a supported horizontal surface 102;

a DC motor attached below the horizontal surface 104, wherein a circular rotating disc 106 is attached to the DC motor by means of shaft 108 which rotates said disc 106;

a reservoir 110 with an electrospinning element 112 placed perpendicularly above said disc'"'"'s top surface 106a, said electrospinning element 112 having at least a tip, said electrospinning element 112 having a passage by which a substance from which the nanofibers are to be composed is provided to an interior of said tip of the electrospinning element 112, and said electrospinning element 112 configured to electrospin said nanofibers by a high voltage mediated extraction of the substance from said tip of the electrospinning element 112; and

at least a focusing device 114 positioned longitudinally below the electrospinning element 112 tip for focusing the electrospun nanofibers into a defined region on said disc'"'"'s top surface 106a, wherein said focusing device 114 is placed exactly below said tip of the electrospinning element 112 and below said disc'"'"'s bottom surface 106b, said focusing device 114 having axis perpendicular to said disc 106, said focusing device 114 configured to focus the electrospun nanofibre by electric field,

wherein said electrospinning element 112 and said focusing device 114 are connected to the opposite terminals of an external high voltage (DC) power supply.

2. The electrospinning apparatus 100 as claimed in claim 1, wherein the apparatus is enclosed in a plexiglas enclosure.

3. The electrospinning apparatus 100 as claimed in claim 1, wherein said reservoir 110 is a glass syringe with a glass plunger or piston-reservoir system.

4. The electrospinning apparatus 100 as claimed in claim 1, wherein said electrospinning element 112 is a blunt capillary needle with internal diameter of about 0.1 to 1 mm, preferably about 0.4 to 0.6 mm.

5. The electrospinning apparatus 100 as claimed in claim 1, wherein said electrospinning element 112 is a metallic needle.

6. The electrospinning apparatus 100 as claimed in claim 1, wherein said focusing device 114 for focusing the electrospun nanofibers is a needle.

7. The electrospinning apparatus 100 as claimed in claim 6, wherein said needle is made of metal, preferably stainless steel.

8. The electrospinning apparatus 100 as claimed in claim 1, wherein said electrospinning element 112 and said disc 106 are at a distance ranging from 4 cm to 10 cm.

9. The electrospinning apparatus 100 as claimed in claim 1, wherein said disc 106 is made of material having low dielectric constant.

10. The electrospinning apparatus 100 as claimed in claim 1, wherein said disc 106 is made of wood and having thickness ranging from about 1 mm to about 3 mm.

11. The electrospinning apparatus 100 as claimed in claim 1, wherein said disc has a radius of about 5 to 20 cm, preferably about 13 to 15 cm.

12. The electrospinning apparatus 100 as claimed in claim 1, wherein said DC motor 104 rotates said disc at speed ranging from about 1000 rpm to about 2000 rpm.

13. A method of electrospinning to produce electrospun nanofibers by employing the apparatus 100 as claimed in claim 1, said method comprising;

introducing a potential difference between an electrospinning element 112 and a focusing device 114 for focusing said electrospun nanofibers by an external high voltage (DC) power supply;

positioning a circular disc 106 in between said electrospinning element 112 and said focusing device 114 and connecting said disc to a DC motor 104 by means of shaft 108 which rotates said disc 106,

drawing a substance from which the nanofibers are to be composed from said reservoir 110 by means of said tip of the electrospinning element 112 towards said focusing device 114 for focusing the electrospun nanofibers into a defined region on said disc'"'"'s top surface 106a positioned longitudinally below said electrospinning element 112 tip, said region is coated with a non-conducting substrate; and

collecting said substance as electrospun nanofiber on the said region of said disc surface 106a at position exactly longitudinally above said focusing device 114, wherein said electrospun nanofiber is in aligned form, and

optionally discontinuing said power supply;

rotating said non-conducting substrate by 90°

; and

re-introducing said power supply to obtain said aligned electrospun nanofiber on said non-conducting substrate coated over said disc surface 106a in crossed form.

14. The method as claimed in claim 13, wherein said non-conducting substrate is plastic tape.

15. The method as claimed in claim 13, wherein said aligned nanofiber forms concentric rings having fiber diameter ranging from about 800 nm to about 1200 nm.

16. The method as claimed in claim 13, wherein said potential difference ranges from 5 kV to 25 kV.

17. The method as claimed in claim 13, wherein said substance is a polymeric substance selected from a group consisting of homopolymer, copolymer and polymer blends.

18. The method as claimed in claim 13, wherein said substance is selected from a group consisting of polystyrene, poly(lactic acid), poly(lactide-co-glycolide), chitosan, gelatin, polyvinyl alcohol, polyaniline (PANI)/PEO blend, polyurethanes, polyethylene-co-vinyl acetate, polycaprolactone, PCL, polyethylene glycol, poly(ethylene-co-vinyl alcohol), chitin, collagen, collagen-PEO, silk, silk/PEO blend and hyaluronic acid.

19. The method as claimed in claim 13, wherein said defined region on the disc 106 is at a radial distance ranging from about 7 cm to about 13 cm.