Fabrication of nylon-66 membranes coated with violacein pigment for wound dressing application

Abstract

Wound dressing is used for effective wound healing and a suitable material must be used to cover wound. Nylon was chosen because it has high mechanical strength and has hydrophilic properties compared to other polymers. The incorporation of violacein pigment as natural antibacterial agent onto the nylon membranes will give added value to the wound dressing application. Two methods of fabrication were carried out which were electrospinning and casting technique. Based on the images obtained from Field Emission Scanning Electron Microscope (FESEM), the morphology of nylon membrane was made up of nanofibers which indicated the production of high surface area to volume ratio of electrospun membrane. Furthermore, the tensile strength of electrospun membrane, 8.0292 MPa is higher compared to casted membrane,3.284 MPa which shows better elasticity. By using Differential Scanning Analysis-Thermogravimetric Analysis (DSC-TGA), the decomposition temperature and the melting temperature of nylon membrane is high which are in the range of 477-485ᴏC and 250-254ᴏC respectively, showing it has high thermal resistance compared to other polymers. From Attenuated Total Reflection-Fourier Transform Infrared Spectrospcopy (ATR-FTIR) results, there is a presence of C=C aromatic absorption indicating the presence of violacein pigment in the nylon membrane. Furthermore, the release rate of electrospun nylon-violacein membrane is higher than casted nylon-violacein membrane. For antibacterial test, the nylon-violacein membrane showed effective inhibition against Gram-positive bacteria but negative result towards Escherichia coli (Gram-negative). By comparing these two methods, we can conclude that electospinning technique is more suitable compared to casting technique in order to fabricate desired wound dressing. Also, the use of nylon materials as fabric and violacein pigment as natural antibacterial agent in wound dressing application are beneficial for effective wound healing.