ElectrospinTech
Rotating drum electrospinning setup for spinning of aligned fibers
This work by ElectrospinTech is licensed under a Creative Commons Attribution 3.0 Unported License.
Purpose
This standard describes the assembly and optimization of the electrospinning process to construct aligned nanofibers using a rotating drum.
WARNING: High voltage used in electrospinning can result in serious injury if proper safety precautions are not taken.
|
Disclaimer Any instruments and materials mentioned in this standard are for reference only. Electrospintech does not guarantee its availability or quality. Electrospintech does not guarantee the quality and the result of any experiments based on this procedure. This standard does not address all safety and health issues regarding the performance of the experiment and/or the end product if any. It is the responsibility of the user to establish appropriate controls, safety and health practices. Local regulatory controls and limitation shall be addressed by the users of this standard prior to its use. |
1. Introduction
Electrospinning is a simple process used in the production of fibers generally in the range of hundreds of nanometers to the tens of microns. In a typical setup, the fibers are collected in the form of nonwoven membrane on a flat plate collector. To collect aligned fibers, one of the easiest methods is to use a rotating drum to wind the fibers around its circumference. This method has the advantage of relatively high production rate compared to others such as parallel plate collector. However, the ability to generate aligned fibers depend polymer-solvent combinations and may not be applicable for all. The degree of fiber alignment is also subjective.
2. Equipment and consumables
2.1 Electrospinning setup components and consumables
| Description | Specification | Example |
| High voltage power supply | Voltage: 0 to 30 kV Current: 0.5 mA to 1.5 mA Note: Request for output cable Ensure there is an earth terminal on the instrument |
|
| Syringe pump |
Extrusion syringe pump Able to fit in syringe up to 20 ml |
|
| Hypothemic needle |
Gauge: 27G Preferable flat tip |
|
| Syringe |
5 ml plastic Luer lock (Do not use needle with slip-on design) |
|
| Alligator/crocodile clips | Quantity: 2 to 3 | |
| Extra wires for linking setup to earth terminal | ||
| Fumehood | ||
| Mandrel with motor | Motor rotation speed up to 3000 rpm | See Figure 1 for sample image |
| Aluminum foil | ||
| Cutter | Cutting edge of blade with thickness less than 2 mm |
Rotating drum
|
Assembly
|
Rotating Drum Main body specifications
|
| Figure 1. Sample diagram of setup. |
2.2 General lab equipment, PPE and consumables
| Description | Specification | Example |
| Double sided adhesive tape | ||
| Paper wipes | ||
| *Optical Microscope | ||
| *Techometer (measuring rotation speed) | ||
| Lab coat | Long-sleeved | |
| Glove | ||
| Facemask | ||
| Goggles | Fully covered, chemical resistant |
3. Procedures
3.1 Preparing the collector
Prepare an aluminium foil of dimension 255 x 200 mm
Stick the double sided adhesive tape along the width, at both edges of the aluminium foil as shown in the figure 2.
 Figure 1. Position of double-sided adhesive on aluminium sheet. |
Stick the aluminium foil on the mandrel using the adhesive and wrap it round the mandrel and secure the other end using the adhesive at that end.
3.2 Assembling the electrospinning setup
Prepare the electrospinning setup as per SOP-ES1001. Replace the flat-plate collector with the rotating drum collector.
3.3 Fiber spinning
WARNING: Ensure the high voltage power supply is switched off and the voltage is set to zero- Switch on the power to the motor and tune the rotation speed to the desired rpm (revolution per minute).
Note: To obtain aligned fibers, a rotation speed of greater than 1000 rpm is generally required. - Switch on the syringe pump.
- When a drop of solution emerges from the tip of the needle, switch on the high voltage power supply. Turn up the voltage until the solution drop starts to contort and a jet is observed to form at the tip. Generally, this voltage is about 6 kV and above depending on the solution.
-
Lower the fumehood sash to reduce exposure to aerosol and fibers.
NOTE: Extra precautions are required when spinning hazardous solution.
3.4 Examination of collected fiber
Perform the necessary electrospinning stoppage procedure (See SOP-ES1001)
Use a cutter to slit the aluminium foil along the groove.
Remove the aluminium foil and examine the collected fiber under an optical microscope.
4. Storage
Residual or trace amount of solvent may still be present in the collected fibrous membrane. It is recommended that the membrane be kept in the fumehood with the blower switched on or other appropriate drying equipment for at least 24h to reduce exposure to the solvent coming from the membrane
NOTE: Instruments like SEM and TEM are sensitive to the presence of solvents and vapors. Examination of collected membrane using such instruments should only be carried out after a day of drying.
5. Safety
5.1 Chemical safety
Consult the Material Safety Data Sheet (MSDS) provided by the chemical supplier or over the internet if you are unsure of any hazard posed by the chemical in use.
Preparation of solution especially involving hazardous substance must be carried out in the fumehood.
5.2 Personal protective equipment (PPE)
Full chemical resistant goggles to reduce exposure of the eye to solvent vapor, particles or fibers
Long sleeved laboratory coat to reduce exposure and contamination of skin and personal wear to spills, particles or fibers
Facemask to reduce exposure of the eye to solvent vapor, particles or fibers. (For organic solvents, use half-mask (eg. 3M Half Facepiece Reusable respirator 7500 series) with cartridge that removes or adsorb organic solvents (eg. 3M Gas and Vapor Cartridge 6000 series).
Compatible gloves (latex, nitrile)
5.3 Electrospinning safety precaution
Do not touch the syringe pump, syringe, needle or the high voltage power cable with you hand when the power supply is switched on. If clogging of the needle tip occurs, either shut down the spinning process or use an insulated tool to remove the clog.
6. Disposal
WARNING: Most countries have strict regulation regarding proper disposal of chemicals especially toxic materials and solvents. In general, DO NOT pour unused solution down the sink if you are unsure of its environmental hazard.
Currently, there is no official warning regarding exposure to electrospun polymeric nanofibers. Thus routine disposal method for general lab constructs may be followed unless otherwise stipulated by local regulation.
Glass bottle used to contain solution for electrospinning should be left in the fumehood to dry (unless the solution is known to be non-toxic) before cleaning.
7. References
Last updated: 23 Dec 2013
