Versatile nanofibres from banana
doi:10.1038/nindia.2012.44 Published online 29 March 2012
Researchers have devised a simple and low-cost method for producing highly biocompatible nanofibres from banana pseudo-stem, a waste material. The nanofibres, mostly of cellulose, could be used to make biocomposites for applications in packaging.
The researchers collected mature banana pseudo-stem from banana plant (Musa sapientum) grown in Marthandom, Tamil Nadu. The raw fibres were chopped and exposed to steam in an autoclave, followed by acid and alkali treatment, to yield banana nanofibres.
The steam explosion and acid treatment removed impurities and dissolved the hemicellulose and lignin components, thus increasing the cellulose content of the nanofibres. The researchers studied the surface properties of the nanofibres at various stages of the thermochemical treatment using a technique called inverse gas chromatography.
The researchers found that the steam explosion removed non-cellulosic protective coating compounds from the surface of the nanofibres, leaving it richer in pure cellulose. The surface area increased significantly (by 73–81%) due to the acid treatment, with further increases (2–3%) with rising acid concentration.
The cellulose nanofibres were almost pure crystalline cellulose fibres. This makes them cellulose nanofibres, rather than merely 'banana nanofibres'. "Because pure cellulose has a variety of properties, its nano-form can find applications in various industrial and biomedical fields," says N. Cordeiro, one of the researchers.
- Cordeiro, N. et al. Monitoring surface properties evolution of thermochemically modified cellulose nanofibres from banana pseudo-stem. Carbohydr. Polymer. 88, 125-131 (2012)