A scanning tip electrospinning source for deposition of oriented nanofibres

Abstract

We present a method for controlled deposition of oriented polymeric nanofibres. The method uses a microfabricated scanned tip as an electrospinning source. The tip is dipped in a polymer solution to gather a droplet as a source material. A voltage applied to the tip causes the formation of a Taylor cone, and at sufficiently high voltages, a polymer jet is extracted from the droplet. By moving the source relative to a surface, acting as a counter-electrode, oriented nanofibres can be deposited and integrated with microfabricated surface structures. For example, we deposited fibres of polyethylene oxide with diameters ranging from 100 to 1800 nm, with the diameter primarily depending on the concentration of the polymeric solution. In addition to the uniform fibre deposition, the scanning tip electrospinning source can produce self-assembled composite fibres of micro-and nanoparticles aligned in a polymeric fibre. We also deposited oriented conductive polymeric fibres of polyaniline and investigated the conductivity of these fibres as components for polymeric nanoelectronics.

Hierarchically Structured Electrospun Fibers

“…The use of an insulating collector enhanced the pattern formation by increasing the charge accumulation at the collector [71]. Another method used to generate patterned fiber mats is the controlled deposition of fiber using direct-write methods, sometimes referred to as Near Field Electrospinning (NFES) or Scanned Tip Electrospinning Deposition (STED) [72][73][74][75][76]. This process generally uses conductive tips rather than needles with extremely small tip-sample separations [8,77].…”

“…The benefit of this technique is that micro-meter-sized patterns can be generated within the resolution limits of the linear motion stage utilized for collection. Kameoka et al was able to use the STED method to deposit aligned nanoparticles in a polymeric fiber [76].…”

A method to integrate patterned electrospun fibers with microfluidic systems to generate complex microenvironments for cell culture applications

“…61 Controlled fiber deposition is typically achieved by reducing the distance to the collector to a point below that of the occurrence of bending instabilities, thus leading to controlled deposition through a straight fiber path. [62][63][64][65] For instance, in one implementation of these methods, referred to as direct writing, Brown and co-workers utilized melt electrospinning of poly(-caprolactone) to fabricate hierarchical electrospun structures by means of a translating collector stage to control fiber localization on a substrate. 61 In this manner, surface morphologies of various geometrical arrangements were achieved, including novel three-dimensional scaffold structures based on fiber stacking.…”

Fabrication of Conducting Polymer Nanowires

“…Kameoka et al (2003) presented a method for the controlled deposition of oriented nanowires with the rotation of collectors using a chopper motor. Although this method is not limited by nonwoven shape, it still has limits compared with other methods.…”